Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Epidemiological, life style, and occupational factors associated with lower limb varicose veins: a case control study

Epidemiological, life style, and occupational factors associated with lower limb varicose veins:... Background: Few data were documented about risk factors for lower limb varicose veins (LLVV) among Egyptian population. Identifying modifiable risk factors is crucial to plan for prevention. The current research aims to study the epidemiological, life style, and occupational factors associated with LLVV in a sample of Egyptian population. Methods: A case control study was adopted. Cases with LLVV (n = 150) were compared with controls (n = 150). Data was collected using an interview questionnaire and clinical assessment. Data was analyzed using the univariate and multivariate logistic regression analyses. Results: According to multivariate analysis among all participants (n = 300), the odds of LLVV was 59.8 times greater for those who frequently lift heavy objects (95% CI = 6.01, 584.36) and 6.95 times higher for those who drink < 5 cups of water/ day (95% CI = 2.78, 17.33). Moreover, it was 4.27 times greater for those who infrequently/never consume fiber-rich foods (95% CI = 1.95, 9.37) and 3.65 times greater for those who stand > 4 h/day (95% CI = 1.63, 8.17). Additionally, odds of LLVV was 3.34 times greater for those who report irregular defecation habit (95% CI = 1.68, 6.60), and 2.86 times higher for those who sleep < 8 h/day (95% CI = 1.14, 7.16), and 2.53 times higher for smokers compared with ex-smokers/non- smokers (95% CI = 1.15, 5.58). In addition, a standing posture at work was an independent predictor of LLVV among ever employed participants (n = 234) in the current study (OR = 3.10; 95% CI = 1.02, 9.38). Conclusions: This study highlighted seven modifiable independent predictors of LLVV mostly related to the life style, namely, frequent lifting of heavy objects, drinking < 5 cups of water/day, infrequent/no consumption of fiber-rich food, standing more than 4 h/day, irregular defecation habit, sleeping less than 8 h/day, and smoking. These findings provide a basistodesignanevidence-basedlow-coststrategy for prevention of LLVV among Egyptian population. Keywords: Epidemiological factors, Life style, Occupational factors, Varicose veins 1 Introduction ulceration [1]. Lower limb varicose veins (LLVV) may Chronic venous disease (CVD) is a prevalent condition occur as a primary disease as a result of an internal bio- that tends to worsen with age. Symptoms of CVD in- chemical or morphologic abnormality of the vein wall or clude leg pain, discomfort, and heaviness, whereas the as a result of secondary causes such as thrombosis or clinical signs are varicose veins, edema, skin discolor- obstruction of deep veins, superficial thrombophlebitis, ation, lipodermatosclerosis, and in severe cases, venous arteriovenous fistulas, and pressure on the abdominal veins during pregnancy or from a tumor [2]. Although LLVV seem to be simple cosmetic with benign nature * Correspondence: noha.alshaaer@alexmed.edu.eg; elshaer.n@gmail.com Industrial Medicine and Occupational Health, Community Medicine problem, they can be a source of serious complications Department, Faculty of Medicine, Alexandria University, Champolion Street, El which can lead to missed work days, lower quality of life, Azareeta, Alexandria 21131, Egypt and even loss of a limb or life [3]. Full list of author information is available at the end of the article © The Author(s). 2021 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 2 of 11 Globally, according to Davies review (2019), recent and occupational factors associated with LLVV among evidence supports the trends of varicose vein case rates cases attending vascular surgery clinic at the Alexandria of 51.9 cases per 1000 women and 39.4 cases per 1000 Main University Hospital, Egypt, as determining men. It also shows that the prevalence of CVD and vari- the modifiable risk factors would be helpful in establish- cose veins vary widely by region, though they are highest ing an evidence-based strategy for prevention of LLVV in Western countries [1]. A comprehensive review evalu- among Egyptian population. ated articles published in the English language over more than 55 years, and revealed prevalence estimates 2 Methods for varicose veins of < 1 to 73% in women and 2 to 56% 2.1 Research design and setting in men. The reported wide ranges in prevalence estima- A case control study was conducted at the vascular sur- tions reflect differences in the population distribution of gery outpatient clinic and ophthalmology outpatient risk factors, accuracy in application of diagnostic criteria, clinic at the Alexandria Main University Hospital from and the quality and availability of medical diagnostic and January through May 2019. The field work was con- treatment resources [4]. In Egypt, Aly et al. cross- ducted over a 5-month period, two visits per week at sectional study (2020), conducted on women, found that each outpatient clinic. 51.1% of women (aged 15-55 years old) had varicose veins [5]. 2.2 Participants Previous studies described the non-modifiable factors 2.2.1 Selection of cases associated with LLVV such as positive family history of Cases attending the vascular surgery outpatient clinic varices, increasing age, woman gender, and pregnancy during the period of the study were examined by a [4, 6]. On the other hand, the association between modi- consultant of vascular surgery to identify cases meeting fiable factors such as life style and occupational factors the case definition of LLVV. The case definition includes and the development of LLVV were debated. There is an dilated, tortuous, and palpable subcutaneous veins ongoing controversy as to whether obesity is a primary typically larger than 3-4 mm in diameter mostly in the risk factor for LLVV, or it acts as an aggravating factor legs and ankles [16]. Cases of LLVV were diagnosed and only [7]. In addition, few studies examined the effect of classified using the Clinical, Etiologic, Anatomic, Patho- estrogen therapy, hormone replacement therapy, phys- physiologic classification system of chronic venous insuf- ical activity, hypertension, diabetes mellitus, and trau- ficiently (CEAP) [17], which is widely accepted in the matic injury to the extremities on LLVV [8, 9]. clinical and scientific communities. The classification Low dietary fiber intake, irregular defecation, and was developed in an effort to incorporate use of duplex straining at initial bowel movements have been sug- scanning in the diagnosis, and standardize evaluation for gested as risk factors for LLVV, but the findings have comparison of outcomes across clinical studies. CEAP been inconsistent [4, 6]. In addition, effect of smoking includes clinical symptoms such as pain, presence of habit and smoking intensity on the development of varicose veins, edema, hyperpigmentation, and ulcer. It LLVV is debated [10–12]. Smoking may affect veins also considers the etiology (primary or secondary), ana- through oxidative stress, hypoxia (through carbon tomic distribution and position, pathogenic mechanism monoxide and nitric oxide fixation to hemoglobin), and (venous reflux, obstruction, or both), and produces a endothelial damage; however, mechanisms leading to score based on the severity of the disease [17]. During tissue damage are uncertain [13]. the study period, a total of 168 cases meeting the diag- Occupational mechanical exposure in term of pro- nostic criteria were examined, of whom 150 agreed to longed standing, sitting, walking, and lifting heavy ob- participate in the study. jects have also been examined in a number of studies, of which some found a positive association with LLVV [4, 2.2.2 Selection of controls 6], while other did not [8]. A study goes even so far to An equal number of controls (n = 150) was selected suggest a reverse relationship between prolonged sitting from the ophthalmology outpatient clinic of the same posture and prevalence of LLVVs, while confirming the hospital. The same procedure (CEAP) was used to ex- impact of a prolonged standing posture of the occur- clude the presence of LLVV by the same consultant of rence of LLVV [4]. vascular surgery. In the current study, patients with past In Egypt, although venous diseases are one of the most history of thrombosis, or refused to participate in the common medical problems, there is few documented study were excluded. data about risk factors for LLVV among Egyptian popu- lation; those studies were done long time ago [14, 15]. It 2.2.3 Power analysis was essential to update data; therefore, the current study A power analysis was conducted using the Open Source was conducted to study the epidemiological, life style, Epidemiologic Statistics for Public Health (OpenEpi) [18] Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 3 of 11 to ensure that the number of identified cases will detect a half siblings); history of immobilization for 1-3 difference between cases and controls. The power analysis months; and history of leg trauma (sprains, strains, showed that enrolling 150 cases of LLVVs and 150 con- fractures, or joint dislocation). trols is capable to detect the least difference in the prob- ability of exposure between cases and controls of 14% in 2.3.1.3 Occupational factors respect to major risk factors, with an expected odds ratio of 2.2 at a power of 81.36% and confidence level of 0.95 (α  Employment status. Participants were categorized =0.05). into two categories: ever and never employed. The ever employed includes participants who are 2.3 Research tools currently employed, retired, or those with past Data was collected from cases and controls using a pre- occupations. Ever employed participants were designed and pre-tested interview questionnaire and classified according to the International Standard clinical examination. Classification of Occupations (ISCO) [21]. Duration of employment in years. 2.3.1 Interview questionnaire was conducted to collect the  Working hours/day and working hours/week. following data  Work time (daytime or shift work) Nature of work. Participants were classified into 2.3.1.1 Sociodemographic data Including participants’ white collar (performing professional, managerial, or age, sex, rural/urban residence, education attainment, administrative work), pink collar (related to and marital status. customer interaction, entertainment, sales, or other service oriented work), and blue collar (job requires 2.3.1.2 Epidemiological and life style factors manual labor) [22]. Posture at work. Spending more than half their Level of activity. Regular physical exercise lifetime working hours engaged in particular posture (exercising for 150 min of moderate intensity (standing, sitting, walking, and lifting heavy objects). aerobic physical activity throughout the week as running, walking, swimming, or spinning) [19]; 2.4 Clinical examination was conducted to collect the frequency of lifting heavy objects/day; standing following data: hours/day; sleeping hours/day; and sitting hours/day. 2.4.1 Anthropometric measurements Smoking habit. Inquiry was made into smoking Weight and height was obtained following standard pro- habit and participants were classified into current cedures, and body mass index (BMI) was computed to smoker (still smoking at least one cigarette daily for classify participants into underweight (BMI < 18 kg/m ), as long as 1 year), ex-smoker (quit smoking for at normal weight (BMI from 18.5 to < 25kg/m ), over- least 6 months prior to the date of the study), and weight (BMI from 25 to < 30kg/m ), and obese (BMI ≥ non-smoker (never smoked or smoked less than one 30 kg/m )[23]. pack per month or 20 packs in his/her whole life) [11]. Among smokers, smoking index (SI) was 2.4.2 Clinical examination of lower limbs calculated by multiplying the number of cigarettes Participants were subjected to a clinical examination of smoked per day by long life duration of smoking in the lower limbs by a consultant of vascular surgery to as- years. Smokers were classified according to their SI certain or exclude the presence of LLVVs. Cases were into light smokers (SI < 200), moderate smokers (SI classified into six categories following the CEAP system = 200-400), and heavy smokers (SI > 400) [20]. [17]including:C , no visible or palpable signs of cardio- Dietary habits and intestinal motility. Frequency vascular disease (CVD); C , telangiectasia or reticular of eating diet rich in fibers (fruit, dark green veins; C , varicose vein > 4 mm in diameter; C ,edema as 2 3 vegetables, orange vegetables, legumes, and whole a sequel of varicose vein; C , skin changes (pigmentations, grains); drinking water/day; regularity of defecation venous eczema, etc.); C , skin changes with healed ulcera- times/day; posture while defecation (sitting/squatting). tions; and C , skin changes with active ulcerations [17]. Reproductive history of married women. Gravidity; parity; and the use of oral contraceptives (OCs). 2.5 Statistical analysis Family and medical history. Positive family history The SPSS v.20 (IBM Corp. Released 2011. IBM SPSS of varices (LLVV, hemorrhoids, varicocele) among Statistics for Mac, Armonk, NY, USA) was used for data first degree relatives (parents, full siblings, or entry and analysis. Data was described using number children) and second degree relatives (grandparents, and percentages as well as mean and standard deviation. grand-children, aunts, uncles, nephews, nieces, or Univariate logistic regression analysis was done to Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 4 of 11 compute the odds ratio (OR) and the associated 95% 18.0%) resulting in an estimated risk of 1.95 (95% CI = confidence interval (95% CI) to quantify the risk of 1.13, 3.36). Smokers with LLVV were 6.27 times more LLVVs associated with the potential related factors. likely to be moderate or heavy smokers (95% CI = 1.70, Multivariate logistic regression analysis was conducted 23.16) and have a significantly higher smoking index to model LLVVs as a function of sociodemographic, (OR = 1.006; 95% CI = 1.001, 1.01) (Table 2). epidemiologic, life style, and occupational risk factors. Relative to controls, cases with LLVVs were signifi- As occupational risk factors were applicable only to ever cantly more likely to report never or infrequently con- employed participants (n = 234), two multivariate regres- suming diet rich in fibers (OR = 8.76; 95% CI = 5.16, sion models were constructed. The first one was a step- 14.86), drink less than 5 cups of water/day (OR = 14.57; wise multivariate logistic regression analysis including all 95% CI = 7.68, 27.62), and have irregular defecation participants (n = 300), in which the potential epidemio- habit (OR = 5.03; 95% CI = 3.07, 8.24). Compared with logical and life style risk factors that were significant in controls, a significantly higher percentage of cases with univariate analysis were considered in addition to age, LLVVs reported squatting posture during defecation gender, employment status, and family history of varices. (16.7% compared to 1.3%) and taking laxatives (20.7% The second model was a stepwise model limited to the compared to 4.7%). Cases were 14 times more likely to ever employed participants (n = 234) in which the afore- squat during defecation (OR = 14.80; 95% CI = 3.43, mentioned factors were considered in addition to the 63.71) and 5 times more likely to take laxatives (OR potential occupational risk factors to study their inde- = 5.32; 95% CI = 2.26, 12.51). Cases with LLVV were pendent effect. significantly more likely to be overweight or obese Significance of the obtained results was judged at the (BMI ≥ 25 kg/m ) than controls (OR = 2.57; 95% CI 5% level (α = 0.05). The explained variance of logistic = 1.09-6.08) (Table 2). regression models was determined by the Nagelkerke’s Reproductive factors were examined among married, R and Hosmer and Lemeshow goodness-of-fit test. widowed, and divorced women in the current study Significant factors in univariate analysis that include cells (cases n = 81, controls n = 75); 70.4% of women with having a count less than 5 were excluded from the LLVV reported having the disease after the first preg- multivariate analyses to avoid distortion of the model. nancy. Women with LLVV were significantly more likely to have high gravidity (≥ 4 times) (OR = 4.2; 3 Results 95% CI = 1.97, 8.95), and to have high parity (≥ 4 According to CEAP classification system, the majority of times) (OR = 7.51; 95% CI = 2.91, 19.33) than con- cases with LLVV were categorized as C2 (72.0%, n = trols. Furthermore, women with LLVV tended to use 108) and C3 (28.0%, n = 42). In addition, cases with OCs 5.20 times higher than controls (95% CI, 2.34- LLVV reported symptoms such as pain (96.0%, n = 144), 11.53). Among OCs users (cases n = 36, controls n = lower limb edema (27.3%, n = 41), while bleeding or ul- 10), the mean duration of use of OCs was signifi- cers were not reported. Among cases, 82.7% have re- cantly higher among cases with LLVV (6.91 ± 3.21) ceived conservative treatment, 24.7% reported frequent compared with controls (3.30 ± 2.83) (OR = 1.47; leg raising to alleviate symptoms, and 14% reported fre- 95% CI = 1.10, 1.97) (Table 2). quent wearing compression stoking. Regarding family and medical history, cases with LLVV Univariate analysis revealed insignificant differences in tended to have a positive family history of varices 1.73 the age and sex distribution of cases and controls. The times higher than controls (95% CI = 1.06, 2.82); they re- mean age of cases was 49.90 ± 12.09 years compared with ported positive family history of LLVV, varicocele, and 50.26 ± 10.98 years among controls (p =0.78). However, hemorrhoids (87.9%, 6.9%, and 5.2% respectively). Further- cases were 4 times more likely to report never been to more, cases with LLVV were significantly more likely to school or completed their basic education compared with have a history of leg trauma than controls (OR = 9.51; controls (OR = 4.07; 95% CI = 2.51, 6.62) (Table 1). 95% CI = 1.19, 76.03) (Table 2). Cases of LLVVs were 45.34 times more likely to report Cases and controls were comparable in respect to their lifting heavy objects (OR = 45.34; 95% CI = 6.12, 345.94). employment status (p = 0.78). Among ever employed Cases were significantly more likely to report standing for participants (cases n = 118 and controls n = 116); the more than 4 h daily (OR = 6.95; 95% CI = 4.08, 11.86) and majority of cases with LLVV were plant or machine to sleep less than 8 h per day (OR = 5.51; 95% CI = 3.02, operators (38.1%) and craft workers (27.1%), while the 10.04). No excess risk was found between cases and nei- majority of controls were technicians/associated ther controls in respect to exercising nor the number of professionals (37.1%) and service/sales workers hours spent sitting each day (Table 2). (18.1%) (Table 3). An excess of smokers was encountered among cases of Cases with LLVV were significantly more likely to LLVV compared with controls (30.0% compared with work more than 8 h/day than controls (OR = 2.82; 95% Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 5 of 11 Table 1 Sociodemographic characteristics of studied patients attending the vascular surgery and ophthalmology outpatient clinics at the Alexandria Main University Hospital, 2019, Egypt Sociodemographic Cases Controls OR (95% CI) P value characteristics (n = 150) (n = 150) No. % No. % Gender Male 68 45.3 74 49.3 1.17 (0.74, 1.84) 0.48 Female 82 54.7 76 50.7 Residence Rural 13 8.7 5 3.3 0.36 (0.12, 1.04) 0.05* Urban 137 91.3 145 96.7 Level of education Unschooling/basic education 108 72.0 58 38.7 4.07 (2.51, 6.62) >0.001*** Secondary/higher education 42 28.0 92 61.3 Marital status Never married 4 2.7 5 3.3 1 Married 111 74.0 121 80.7 1.14 (0.30, 4.37) 0.84 Widowed 19 12.7 16 10.7 1.48 (0.34, 6.47) 0.59 Divorced 16 10.7 8 5.3 2.50 (052, 11.9) 0.25 Age (years) Min-max 25-70 28-75 Mean ± SD 49.90 ± 12.09 50.26 ± 10.98 0.99 (0.98, 1.02) 0.78 SD standard deviation, OR odds ratio, CI confidence interval Reference category *p≤0.05 ***p>0.001 CI = 1.56, 5.11), and to work more than 48 h/week than factors were adjusted for gender, employment status, controls (OR = 2.53; 95% CI = 1.41, 4.53). In addition, and family history of varices. This model was able to cases with LLVV tended to have shift work 65.93 times correctly classify 87.0% of cases and 81.0% of controls higher than controls (OR = 65.93; 95% CI = 8.88, in thecurrent study(Table 4). 489.06), and to be a blue/pink collar 4 times higher than Among ever employed participants (n = 234), the controls (OR = 4.00; 95% CI = 2.28, 7.04). Regarding stepwise logistic regression model, which aimed at posture at work, cases with LLVV were significantly studying the independent effect of occupational risk more likely to stand at work for more than 4 h/working factors, revealed that standing posture at work was an day than controls (OR = 6.45; 95% CI = 3.47, 11.98), and independent predictor of LLVV (OR = 3.10; 95% CI = to sitatwork for equaltoorless than4 h/working 1.02; 9.38), in addition to other epidemiological and day than controls (OR = 5.54; 95% CI = 3.05, 10.06) life style predictors. This model was able to correctly (Table 3). classify 87.3% of the cases and 82.0% of the controls According to the stepwise logistic regression in thecurrent study(Table 5). analysis conducted among all participants (n = 300) in the current study, the independent predictors of 4 Discussion LLVVs were as follows: frequent lifting of heavy The current study identified important modifiable life objects (OR = 59.79; 95% CI = 6.01, 584.36), drinking style and occupational risk factors for the development < 5 cups of water/day (OR = 6.95; 95% CI = 2.78, of LLVV. Frequent lifting of heavy objects, drinking < 5 17.33), infrequent/no consumption of fiber-rich food cups of water/day, infrequent/no consumption of fiber- (OR = 4.27; 95% CI = 1.95, 9.37), standing more than rich food, standing more than 4 h/day, irregular 4 h per day (OR = 3.65; 95% CI = 1.63, 8.17), irregu- defecation habit, sleeping less than 8 h/day, and smoking lar defecation habit (OR = 3.34; 95% CI = 1.68, 6.60), were independent predictors of LLVV. In addition, sleeping less than 8 h per day (OR = 2.86; 95% CI = standing posture at work was found to be an independ- 1.14, 7.16), smoking (OR = 2.53; 95% CI = 1.15, ent occupational risk factor for LLVV among ever 5.58), and age (OR =1.05; 95% CI = 1.02, 1.09). Those employed participants. Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 6 of 11 Table 2 Epidemiological and life style factors associated with lower limbs varicose veins (LLVV) Epidemiological and life style factors Cases Controls OR (95% CI) P value (n = 150) (n = 150) No. % No. % Level of activity Exercising &^ Yes (regular/irregular) 27 18.0 29 19.3 1.09 (0.61, 1.95) 0.76 No 123 82.0 121 80.7 Lifting heavy objects (frequency/day) Frequent/very frequent 35 23.3 1 0.7 45.34 (6.12, 345.94) >0.001*** Occasional/rare/never^ 115 76.7 149 99.3 Standing hours/day > 4 h/day 89 59.3 26 17.3 6.95 (4.08, 11.86) >0.001*** ≤ 4 h/day^ 61 40.7 124 82.7 Sleeping hours/day < 8 h/day 62 41.3 17 11.3 5.51 (3.02, 10.04) >0.001*** ≥ 8 h/day^ 88 58.7 133 88.7 Sitting hours/day < 8 hours/day 77 51.3 72 48.0 1.14 (0.72, 1.79) 0.64 ≥ 8 hours/day 73 48.7 78 52.0 Anthropometric measurements Body mass index (BMI) Underweight and normal (BMI < 25) 8 5.3 19 12.7 2.57 (1.09, 6.08) 0.02* Overweight and obese (BMI ≥ 25) 142 94.7 131 87.3 Min-max 21.60-48.47 21.48-39.45 Mean ± SD 31.19 ± 4.71 27.68 ± 2.57 1.32 (1.22, 1.44) >0.001*** Smoking Smoking status Smoker 45 30.0 27 18.0 1.95 (1.13, 3.36) 0.01* Ex-smoker/non-smoker 105 70.0 123 82.0 Smoking intensity Light smoker 34 63.0 32 91.4 6.27 (1.70, 23.16) >0.01** Moderate/heavy smoker 20 37.0 3 8.6 Smoking index (SI) Min-max 20-500 25-300 Mean ± SD 188.5 ± 103.6 141.8 ± 73.4 1.006 (1.001, 1.01) 0.02* Dietary habits and intestinal motility Consumption of diet rich in fibers Occasional/rare/never 103 68.7 30 20.0 8.76 (5.16, 14.86) >0.001*** Frequent/very frequent 47 31.3 120 80.0 Drinking water (cups/day) ≥ 5 cups/day 136 90.7 60 40.0 14.57 (7.68, 27.62) >0.001*** ≥ 5 cups/day 14 9.3 90 60.0 Regularity of defecation Irregular 97 64.7 40 26.7 5.03 (3.07, 8.24) >0.001*** Regular 53 35.3 110 73.3 Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 7 of 11 Table 2 Epidemiological and life style factors associated with lower limbs varicose veins (LLVV) (Continued) Epidemiological and life style factors Cases Controls OR (95% CI) P value (n = 150) (n = 150) No. % No. % Posture while defecation Squatting 25 16.7 2 1.3 14.80 (3.43, 63.71) >0.001*** Sitting 125 83.3 14 98.7 Taking laxatives Yes 31 20.7 7 4.7 5.32 (2.26, 12.51) >0.001*** No 119 79.3 143 95.3 Medical and family history Family history of varices Positive family history 58 38.7 40 26.7 1.73 (1.06, 2.82) 0.02* Negative family history/not known 92 61.3 110 73.3 Immobilization for 1-3 months Yes 13 8.7 0 0.0 No 137 91.3 150 100.0 Previous leg trauma Yes 9 6.0 1 0.7 9.51 (1.19, 76.03) 0.01* No 141 94.0 149 99.3 Reproductive factors (n = 81) (n = 75) Gravidity ≥ 4 36 44.4 12 16.0 4.20 (1.97, 8.95) >0.001*** <4 45 55.6 63 84.0 Parity ≥ 4 32 39.5 6 8.0 7.51 (2.91, 19.33) >0.001*** <4 49 60.5 69 92.0 Use of OCs Yes (regular/irregular) 36 44.4 10 13.2 5.20 (2.34-11.53) >0.001*** No 45 55.6 65 86.8 Duration of OCs use (years) < 5 years 5 13.9 7 70.0 14.46 (2.77, 75.3) 0.001** ≥ 5 years 31 86.1 3 30.0 Min-max 1-12 1-10 Mean ± SD 6.91 ± 3.21 3.30 ± 2.83 1.47 (1.10, 1.97) >0.01** Abbreviations: SI smoking index, SD standard deviation, OR odds ratio, CI confidence interval, OCs oral contraceptive pills Reference category Among smokers (cases n = 54, controls n = 35), light smokers (SI < 200), moderate/heavy smokers (SI ≥ 200) Where frequent is ≥ 5 times per week Regular exercise defined as 150 min of moderate intensity aerobic physical activity per week Number of women excluding single women (cases n = 81, controls n = 75) Number of women using OCs (cases n = 36, controls n = 10) *p≤0.05 **p>0.01 ***p>0.001 Age was found to be an independent predictor of between increasing age and varicose veins [10–12, 24, LLVV in the current study; an effect that was masked by 25], no sex-dependent difference in LLVV, and a nega- other factors in univariate analysis, whereas gender and tive relation between family history and varicose veins family history of varices were not associated with risk of [12]. On the contrary, in Ziegler et al. study, age was not LLVV. Similarly, several studies revealed an association a risk factor for varicose veins [26]. Also, some studies Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 8 of 11 Table 3 Occupational factors associated with lower limbs varicose veins (LLVV) Occupational factors Cases Controls OR (95% CI) P value No. % No. % Employment status (n = 150) (n = 150) Never employed 32 21.3 34 22.7 1.08 (0.62, 1.86) 0.78 Ever employed (currently/previously) 118 78.7 116 77.3 Among ever employed (n = 118) (n = 116) Duration of employment (years) Min-max 2-50 2-50 Mean± SD 23.55 ± 13.70 24.50 ± 14.09 0.99 (0.98, 1.01) 0.60 ISCO classification Professionals 3 2.5 22 19.0 1 Technicians and associated professionals 24 20.3 43 37.1 0.27 (0.01, 4.00) 0.34 Service and sales workers 10 8.5 21 18.1 1.11 (0.09, 12.96) 0.93 Skilled agricultural and fishery workers 3 2.5 2 1.7 0.95 (0.07, 11.78) 0.97 Craft and related trade workers 32 27.1 8 6.9 3.00 (0.15, 59.89) 0.47 Plant and machine operators 45 38.1 18 15.5 8.00 (0.64, 99.66) 0.10 Elementary occupations 1 0.8 2 1.7 5.00 (0.42, 58.63) 0.20 Working hours/day Working > 8 h/day 47 39.8 22 19.0 2.82 (1.56, 5.11) >0.001*** Working ≤ 8 h/day 71 60.2 94 81.0 Working hours/week Working > 48 h/week 47 39.8 24 20.7 2.53 (1.41, 4.53) >0.01** Working ≤ 48 h/week 71 60.2 92 79.3 Work time Day work 75 63.6 115 99.1 65.93 (8.8, 489.1) 0.001** Shift work 43 36.4 1 0.9 Nature of work Blue/pink collar 91 77.1 53 45.7 4.00 (2.28, 7.04) >0.001*** White collar 27 22.9 63 54.3 Posture at work Standing 66 55.9 18 15.5 6.91 (3.71, 12.84) >0.001*** Sitting 52 44.1 98 84.5 Sitting hours/working day Sitting ≤ 4 h/ working day 65 55.1 21 18.1 5.54 (3.05, 10.06) >0.001*** Sitting < 4 h/ working day 53 44.9 95 81.9 Standing hours/working day Standing <4 h/working day 64 54.2 18 15.5 6.45 (3.47, 11.98) >0.001*** Standing >4 h/working day 54 45.8 98 84.5 Lifting heavy objects (hours/working day) ≥ 2 h/working day 7 5.9 1 0.9 7.25 (0.87, 59.90) 0.06 < 2 h/working day 111 94.1 115 99.1 ISCO International Standard Classification of Occupations, SD standard deviation, CI confidence interval, OR odds ratio Reference category Number of participants currently/previously employed (cases = 118, controls = 116) **p> 0.01 ***p>0.001 Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 9 of 11 reported association between positive family history and In the current study, never going to school or obtain- varicose veins [6, 27]; the results of studies must be ing only basic education, which is a proxy for low socio- interpreted with caution, as varicose veins are a common economic status, was significantly associated with LLVV. problem, thus, a large proportion of study subjects This could be explained by the fact that level of would report a positive family history. education determines the nature of occupation (blue/ Besides, some studies revealed an association between pink collar vs white collar) which directly affects the de- female gender and varicose veins [10, 11, 24, 26]. Differ- velopment of varices. Among ever employed participants ent distribution of reproductive risk factors among in the current study, 65% of cases with LLVV were plant women in different studies might lead to diverse results. and machine operators and craft workers, while profes- Gravidity, parity, and use of OCs could independently sionals represented 2.5% of cases. Likewise, in other increase the risk of LLVV among women compared with studies, the majority of cases were manual laborers, men, in some studies. Different findings may also be due farmers, house wives, nurses, utility workers, and to different study designs, sample size, and population cleaners [24, 26, 29]. This supports the observation that characteristics. occupation involving violent muscular activity are at The current study as well as previous studies reported high risk for developing varicose veins. Hot and humid the higher risk of LLVVs associated with high parity [4, workplace conditions and socioeconomic may also be 6, 12, 25] and the use of OCs [28]. Beebe-Dimmer et al. implicated [26]. [4] attributed the adverse effects of pregnancy to the in- Among ever employed participants in the current crease in blood volume as well as the increase in intra- study, standing posture at work was found to be an inde- abdominal pressure and central venous return resulting pendent predictor of LLVV. Most studies indicate that from fetal growth and weight gain; the elevated pressure working in a position resulting in protracted orthostasis can result in valve failure and progression of varices. may increase the prevalence and severity of LLVV; a sig- Also, the increase in the levels of relaxin, estrogen, and nificantly higher prevalence of varicose veins was found progesterone during pregnancy play a role in the devel- in employees working in a prolonged standing posture opment of varices. In contrast, other studies did not [6, 24, 26, 30]; while the lowest prevalence was found in support the association of LLVVS with pregnancy [28] medical technician assistants, secretaries, and scientific or the use of hormonal contraceptives [12, 26]. The vari- staff, since these professions have the shortest mean pe- ation in the effect of OCs between this study and that of riods of standing at work [26]. Yun et al. study [12] could be attributed to the difference Regarding physical activity, frequent lifting of heavy in the distribution of reproductive risk factors; all of the objects, standing for more than 4 h/day, and sleeping for women in their study were working nurses and most of less than 8 h/day, were found to be independent predic- them were unmarried. In the current research, the small tors of LLVV in the present study and in Tabatabaeifar number of ever married women and those who ever et al. study [25]. Whereas no relation was found between used hormonal contraceptives precluded studying the in- regular physical exercise and the development of LLVV dependent effect of reproductive factors. in the current study and in Yun et al. study [12]. On the Table 4 Stepwise logistic regression analysis of the independent predictors of lower limb varicose veins (LLVV) among all participants (n =300) Independent predictors Coefficient Adjusted OR 95% CI P value Age 0.05 1.05 (1.02, 1.09) < 0.01** Smoking 0.93 2.53 (1.15, 5.58) 0.02* Infrequent/no consumption of fiber-rich food 1.45 4.27 (1.95, 9.37) < 0.001*** Drinking < 5 cups of water/day 1.94 6.95 (2.78, 17.33) < 0.001*** Irregular defecation habit 1.20 3.34 (1.68, 6.60) < 0.01** Frequent lifting of heavy objects/day 4.09 59.79 (6.01, 584.36) < 0.001*** Standing > 4 h/day 1.29 3.65 (1.63, 8.17) < 0.01** Sleeping < 8 h/day 1.05 2.86 (1.14, 7.16) 0.02* Abbreviations: OR odds ratio, CI confidence interval 2 2 2 2 Model X = 200.91 (p < 0.001); Nagelkerke’sR = 0.65; Cox and Snell R = 0.48; Hosmer and Lemeshow X = 5.57 (p=0.69) OR adjusted for gender, employment status, family history of varices, and potential life style risk factors significant in univariate analysis (posture during defecation, taking laxatives, and body mass index) Occupational risk factors and significant factors that include cells having a count less than 5 were excluded from the regression model *p<0.05 **p<0.01 ***p<0.001 Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 10 of 11 Table 5 Stepwise logistic regression analysis of the independent predictors of lower limb varicose veins (LLVV) among ever employed participants (n = 234) Independent predictors Coefficient Adjusted OR 95% CI P value Standing posture at work 1.13 3.10 (1.02, 9.38) 0.04* Age 0.06 1.06 (1.02, 1.10) <0.01** Frequent lifting of heavy objects/day 3.63 37.59 (3.52, 400.86) <0.01** Standing > 4 h/day 1.26 3.52 (1.20, 10.33) 0.02* Infrequent/no consumption of fiber-rich food 1.45 4.24 (1.70, 10.62) <0.01** Drinking < 5 cups of water/day 2.24 9.42 (3.43, 25.89) <0.001*** Irregular defecation habit 1.87 6.46 (2.73, 15.27) <0.001*** Taking laxatives −1.63 0.20 (0.05, 0.08) 0.02* Abbreviations: OR odds ratio, CI confidence interval 2 2 2 2 Model X = 157.19 (p < 0.001); Nagelkerke’sR = 0.65; Cox and Snell R = 0.48; Hosmer and Lemeshow X = 10.48 (p = 0.23) OR adjusted for gender, family history of varices, and potential occupational and life style risk factors significant in univariate analysis (working hours per week, nature of work, standing hours/working day, sitting hours/working day, body mass index, smoking, posture during defecation, and sleeping hours/day) Significant factors that include cells having a count less than 5 were excluded from the regression model *p<0.05 **p<0.01 ***p<0.001 contrary, in other studies, regular exercising was found risk [30], and smoking pack-years significantly increases to be a protective factor [10, 24]. The difference in find- the odds of varicose veins by 1.12 [10]. It has been hy- ings might be due to different definitions of the regular pothesized that smoking leads to hypoxia, production of exercising term in studies. proinflammatory factors within the vessel wall, biochem- As regard dietary habits and intestinal motility, low ical modifications on the venous endothelium that dietary fiber intake, drinking less than 5 cups of water/ increases the vasomotor tonicity in the venous walls, and day, and irregular defecation were independent predic- lengthening of scarring time which influence the trophic tors of LLVV in the present study and in other studies disorders associated with LLVV [30]. [4, 24, 31] which proposed that constipation and in- Few participants in the present study had a history of creased intra-abdominal pressure contributed to ob- leg trauma and long immobilization which was signifi- struction of venous return. People usually take laxatives cantly associated with LLVV in accordance with Abelyan to regulate their irregular bowel movement; this explains et al. study [10]. In contrast, Yun et al. study found no the change in findings in the present study, where taking significant association between leg injury and varicose laxatives was a risk factor for LLVV in univariate ana- veins [12]. The independent effect of those variables calls lysis, while in multivariate analysis, it had a protective for further studies on a larger sample. effect. Overweight or obesity (BMI ≥ 25) was not a predictor 4.1 Limitations of the study of LLVV in the current study. In Seidel et al. study, the The current case control study (retrospective study) might association between obesity and varicose veins was be subjected to recall bias; cases with LLVVs would prob- found in women but not in men [8]; however, in his ably be more aware of the past medical and family events study, there was an observed gender difference, besides, related to their conditions. Additionally, the relatively parity may act as a confounding factor due to the fact small number of ever married women limited studying the that parous women tend to have high average body independent effect of reproductive factors. weight [8]. In literature, the data on correlation between obesity and varicose veins is controversial; and whether it has an independent or an aggravating effect on the de- 5 Conclusion velopment of varicose veins is still debatable [7]. The present study highlighted seven modifiable inde- Smoking was an independent predictor of LLVV in pendent predictors of LLVV mostly related to the life the current study; smokers had 2.53 times greater risk to style. These findings provide a foundation for planning develop LLVV. Moreover, smoking intensity was signifi- an evidence-based low-cost strategy for prevention of cantly associated with LLVV; moderate/heavy smokers LLVV among Egyptian population. Future studies are had 6.27 times greater risk to develop LLVV. Similarly, recommended to examine cause-effect relationship, and in a multicenter review and in other studies, the propor- evaluate independent effect of reproductive factors on tion of varicose veins cases with history of smoking was the development of LLVV. 19.4%, and 45.6% [29], smokers had 1.8 times greater Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 11 of 11 Abbreviations 6. Robertson L, Evans C, Fowkes F. Epidemiology of chronic venous disease. BMI: Body mass index; CEAP: Clinical, Etiologic, Anatomic, Pathophysiologic; Phlebology. 2008;23(3):103–11. CI: Confidence interval; CVD: Chronic venous disease; ISCO: International 7. Hirai MKN, Nakayama R. Prevalence and risk factors of varicose veins in Standard Classification of Occupations; LLVV: Lower limb varicose veins; Japanese women. Angiology. 1990;41(3):228–32. OCs: Oral contraceptive pills; OR: Odds ratio; SD: Standard deviation; 8. Seidel AC, Belczak CE, Campos MB, Campos RB, Harada DS. The impact of SI: Smoking index obesity on venous insufficiency. Phlebology. 2015;30(7):475–80. 9. DA Brand FN, Abbott RD. The epidemiology of varicose veins: the Framingham study. Am J Prev Med. 1988;4(2):96–101. Acknowledgements 10. Abelyan G, Abrahamyan L, Yenokyan G. A case-control study of risk factors Not applicable. of chronic venous ulceration in patients with varicose veins. Phlebology. 2018;33(1):60–7. Authors’ contributions 11. Lee AJ, Evans CJ, Allan PL, Ruckley CV, Fowkes FGR. Lifestyle factors and the risk SE generated the research idea, and designed the work. ID designed the of varicose veins: Edinburgh Vein Study. J Clin Epidemiol. 2003;56(2):171–9. work, and revised the research article (manuscript) for submission. SM 12. Yun MJ, Kim YK, Kang DM, Kim JE, Ha WC, Ky J, et al. A study on prevalence conducted the clinical examination of the lower limbs for all participants. NE and risk factors for varicose veins in nurses at a university hospital. Safety carried out data analysis and interpretation, and drafted the research article. Health Work. 2018;9(1):79–83. NA collected the data and revised the manuscript for submission. All authors 13. Müller-Bühl U, Leutgeb R, Engeser P, Achankeng EN, Szecsenyi J, Laux G. have read and approved the manuscript. Varicose veins are a risk factor for deep venous thrombosis in general practice patients. Vasa. 2012;41(5):360–5. Funding 14. Darwish I. Some epidemiological features of cases having lower limb Authors report that there was no funding source for the work or the varicose veins attending the main university hospital in Alexandria. Master preparation of the tools. Thesis, Faculty of Medicine: Alexandria University; 1987. 15. Mekky S, Schilling R, Walford J. Varicose veins in women cotton workers. An Availability of data and materials epidemiological study in England and Egypt. Br Med J. 1969;2(5657):591–5. Data and materials are available on reasonable request. Confidentiality and 16. Piazza G. Varicose veins. Circulation. 2014;130(7):582–7. security of data and materials were insured through all stages of the study. 17. Eklöf B. CEAP classification and implications for investigations. Acta Chir Belg. 2006;106(6):654–8. Declarations 18. Dean AG, Sullivan KM, Soe MM. OpenEpi: open source epidemiologic statistics for public health, Version. www.OpenEpi.com, 2013 Ethics approval and consent to participate 19. World Health Organization. Global strategy on diet, physical activity and The study was approved by the Research Ethics Committee of AFM, health. WHO. [Internet] 2018. Available from: http://www/who/int/ University of Alexandria (the committee’s reference number: not applicable). dietphysicalactivity/pa/en An informed written consent was obtained from each participant at the 20. Lee Y, Shin M, Kweon S, Choi J, Rhee J, Ahn H, et al. Cumulative smoking beginning of the study after explanation of the objectives of the study, exposure, duration of smoking cessation, and peripheral arterial disease in procedures, and types of information to be obtained. middle-aged and older Korean men. BMC Public Health. 2011;11(1):94. 21. International Labour Organization Office. The International Standard Classification of Occupations: introduction to occupational classifications. Consent for publication ILO. [Internet] 2018. [cited in 2020, April 2]. Available from: http://www.ilo. Not applicable. org/public/english/bureau/stat/isco/intro.htm. 22. Holland PJHR, Steen J. Human resource strategies and organizational Competing interests structures for managing gold-collar workers. J Eur Ind Train. 2002;26(2-4):80. Authors declare no conflicts of interest. The research was not supported by 23. Papadakis MA, Rabow MW. CURRENT medical diagnosis and treatment. Mc any commercial source; no financial relationships with any organizations that Graw Hill Education Lange 2018;57. might have an interest in the submitted work. 24. Sharif Nia H, Chan YH, Haghdoost AA, Soleimani MA, Beheshti Z, Bahrami N. Varicose veins of the legs among nurses: occupational and demographic Author details characteristics. Int J Nurs Pract. 2015;21(3):313–20. Public Health, Preventive and Social Medicine, Community Medicine 25. Tabatabaeifar S, Frost P, Andersen JH, Jensen LD, Thomsen JF, Svendsen Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt. SW. Varicose veins in the lower extremities in relation to occupational Vascular Surgery Department, Faculty of Medicine, Alexandria University, mechanical exposures: a longitudinal study. Occup Environ Med. 2015;72(5): Alexandria, Egypt. Industrial Medicine and Occupational Health, Community 330–7. Medicine Department, Faculty of Medicine, Alexandria University, 26. Ziegler SEG, Stoger R, Machula J, Rudiger H. High prevalence of chronic Champolion Street, El Azareeta, Alexandria 21131, Egypt. Ministry of Health, venous disease in hospital employees. Wien. Klin. Wschr. 2003;575:9. Austria. Alexandria, Egypt. 27. Bahk JW, Kim H, Jung-Choi K, Jung MC, Lee I. Relationship between prolonged standing and symptoms of varicose veins and nocturnal leg Received: 26 August 2020 Accepted: 11 May 2021 cramps among women and men. Ergonomics. 2012;55(2):133–9. 28. Robertson L, Evans C, Lee A, Allan P, Ruckley C, Fowkes F. Incidence and risk factors for venous reflux in the general population: Edinburgh Vein Study. References Eur J Vasc Endovasc Surg. 2014;48(2):208–14. 1. Davies AH. The seriousness of chronic venous disease: a review of real- 29. Joseph N, Abhishai B, Thouseef MF, Devi U, Abna A, Juneja I. A multicenter world evidence. Adv Ther. 2019;36(S1):5–12. review of epidemiology and management of varicose veins for national 2. Gloviczki P, Comerota AJ, Dalsing MC, Eklof BG, Gillespie DL, Gloviczki ML, guidance. Ann Med Surg. 2016;8:21–7. et al. The care of patients with varicose veins and associated chronic 30. Gourgou S, Dedieu F, Sancho-Garnier H. Lower limb venous insufficiency venous diseases: clinical practice guidelines of the Society for Vascular and tobacco smoking: a case-control study. Am J Epidemiol. 2002;155(11): Surgery and the American Venous Forum. J Vasc Surg. 2011;53(5):S2–48. 1007–15. 3. Raetz J, Wilson M, Collins K. Varicose veins: diagnosis and treatment. Am 31. Lee AJ, Evans CJ, Hau CM, Fowkes FG. Fiber intake, constipation, and risk of Fam Physician. 2019;99(11):682–8. varicose veins in the general population: Edinburgh Vein Study. J Clin 4. Beebe-Dimmer JL, Pfeifer JR, Engle JS, Schottenfeld D. The epidemiology of Epidemiol. 2001;54(4):423–9. chronic venous insufficiency and varicose veins. Ann Epidemiol. 2005;15(3):175–84. 5. Aly SG, Wahdan MM, Ahmed DH, Ibrahim EF. Abd El- Hamid DM. Varicose veins: prevalence and associated risk factors among women of childbearing Publisher’sNote age attending a primary health care unit in Cairo, Egypt. Egypt Fam Med J. Springer Nature remains neutral with regard to jurisdictional claims in 2020;4(1):58–75. published maps and institutional affiliations. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of the Egyptian Public Health Association Springer Journals

Epidemiological, life style, and occupational factors associated with lower limb varicose veins: a case control study

Loading next page...
 
/lp/springer-journals/epidemiological-life-style-and-occupational-factors-associated-with-2LQz6C8UQ0
Publisher
Springer Journals
Copyright
Copyright © The Author(s) 2021
eISSN
2090-262X
DOI
10.1186/s42506-021-00075-0
Publisher site
See Article on Publisher Site

Abstract

Background: Few data were documented about risk factors for lower limb varicose veins (LLVV) among Egyptian population. Identifying modifiable risk factors is crucial to plan for prevention. The current research aims to study the epidemiological, life style, and occupational factors associated with LLVV in a sample of Egyptian population. Methods: A case control study was adopted. Cases with LLVV (n = 150) were compared with controls (n = 150). Data was collected using an interview questionnaire and clinical assessment. Data was analyzed using the univariate and multivariate logistic regression analyses. Results: According to multivariate analysis among all participants (n = 300), the odds of LLVV was 59.8 times greater for those who frequently lift heavy objects (95% CI = 6.01, 584.36) and 6.95 times higher for those who drink < 5 cups of water/ day (95% CI = 2.78, 17.33). Moreover, it was 4.27 times greater for those who infrequently/never consume fiber-rich foods (95% CI = 1.95, 9.37) and 3.65 times greater for those who stand > 4 h/day (95% CI = 1.63, 8.17). Additionally, odds of LLVV was 3.34 times greater for those who report irregular defecation habit (95% CI = 1.68, 6.60), and 2.86 times higher for those who sleep < 8 h/day (95% CI = 1.14, 7.16), and 2.53 times higher for smokers compared with ex-smokers/non- smokers (95% CI = 1.15, 5.58). In addition, a standing posture at work was an independent predictor of LLVV among ever employed participants (n = 234) in the current study (OR = 3.10; 95% CI = 1.02, 9.38). Conclusions: This study highlighted seven modifiable independent predictors of LLVV mostly related to the life style, namely, frequent lifting of heavy objects, drinking < 5 cups of water/day, infrequent/no consumption of fiber-rich food, standing more than 4 h/day, irregular defecation habit, sleeping less than 8 h/day, and smoking. These findings provide a basistodesignanevidence-basedlow-coststrategy for prevention of LLVV among Egyptian population. Keywords: Epidemiological factors, Life style, Occupational factors, Varicose veins 1 Introduction ulceration [1]. Lower limb varicose veins (LLVV) may Chronic venous disease (CVD) is a prevalent condition occur as a primary disease as a result of an internal bio- that tends to worsen with age. Symptoms of CVD in- chemical or morphologic abnormality of the vein wall or clude leg pain, discomfort, and heaviness, whereas the as a result of secondary causes such as thrombosis or clinical signs are varicose veins, edema, skin discolor- obstruction of deep veins, superficial thrombophlebitis, ation, lipodermatosclerosis, and in severe cases, venous arteriovenous fistulas, and pressure on the abdominal veins during pregnancy or from a tumor [2]. Although LLVV seem to be simple cosmetic with benign nature * Correspondence: noha.alshaaer@alexmed.edu.eg; elshaer.n@gmail.com Industrial Medicine and Occupational Health, Community Medicine problem, they can be a source of serious complications Department, Faculty of Medicine, Alexandria University, Champolion Street, El which can lead to missed work days, lower quality of life, Azareeta, Alexandria 21131, Egypt and even loss of a limb or life [3]. Full list of author information is available at the end of the article © The Author(s). 2021 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 2 of 11 Globally, according to Davies review (2019), recent and occupational factors associated with LLVV among evidence supports the trends of varicose vein case rates cases attending vascular surgery clinic at the Alexandria of 51.9 cases per 1000 women and 39.4 cases per 1000 Main University Hospital, Egypt, as determining men. It also shows that the prevalence of CVD and vari- the modifiable risk factors would be helpful in establish- cose veins vary widely by region, though they are highest ing an evidence-based strategy for prevention of LLVV in Western countries [1]. A comprehensive review evalu- among Egyptian population. ated articles published in the English language over more than 55 years, and revealed prevalence estimates 2 Methods for varicose veins of < 1 to 73% in women and 2 to 56% 2.1 Research design and setting in men. The reported wide ranges in prevalence estima- A case control study was conducted at the vascular sur- tions reflect differences in the population distribution of gery outpatient clinic and ophthalmology outpatient risk factors, accuracy in application of diagnostic criteria, clinic at the Alexandria Main University Hospital from and the quality and availability of medical diagnostic and January through May 2019. The field work was con- treatment resources [4]. In Egypt, Aly et al. cross- ducted over a 5-month period, two visits per week at sectional study (2020), conducted on women, found that each outpatient clinic. 51.1% of women (aged 15-55 years old) had varicose veins [5]. 2.2 Participants Previous studies described the non-modifiable factors 2.2.1 Selection of cases associated with LLVV such as positive family history of Cases attending the vascular surgery outpatient clinic varices, increasing age, woman gender, and pregnancy during the period of the study were examined by a [4, 6]. On the other hand, the association between modi- consultant of vascular surgery to identify cases meeting fiable factors such as life style and occupational factors the case definition of LLVV. The case definition includes and the development of LLVV were debated. There is an dilated, tortuous, and palpable subcutaneous veins ongoing controversy as to whether obesity is a primary typically larger than 3-4 mm in diameter mostly in the risk factor for LLVV, or it acts as an aggravating factor legs and ankles [16]. Cases of LLVV were diagnosed and only [7]. In addition, few studies examined the effect of classified using the Clinical, Etiologic, Anatomic, Patho- estrogen therapy, hormone replacement therapy, phys- physiologic classification system of chronic venous insuf- ical activity, hypertension, diabetes mellitus, and trau- ficiently (CEAP) [17], which is widely accepted in the matic injury to the extremities on LLVV [8, 9]. clinical and scientific communities. The classification Low dietary fiber intake, irregular defecation, and was developed in an effort to incorporate use of duplex straining at initial bowel movements have been sug- scanning in the diagnosis, and standardize evaluation for gested as risk factors for LLVV, but the findings have comparison of outcomes across clinical studies. CEAP been inconsistent [4, 6]. In addition, effect of smoking includes clinical symptoms such as pain, presence of habit and smoking intensity on the development of varicose veins, edema, hyperpigmentation, and ulcer. It LLVV is debated [10–12]. Smoking may affect veins also considers the etiology (primary or secondary), ana- through oxidative stress, hypoxia (through carbon tomic distribution and position, pathogenic mechanism monoxide and nitric oxide fixation to hemoglobin), and (venous reflux, obstruction, or both), and produces a endothelial damage; however, mechanisms leading to score based on the severity of the disease [17]. During tissue damage are uncertain [13]. the study period, a total of 168 cases meeting the diag- Occupational mechanical exposure in term of pro- nostic criteria were examined, of whom 150 agreed to longed standing, sitting, walking, and lifting heavy ob- participate in the study. jects have also been examined in a number of studies, of which some found a positive association with LLVV [4, 2.2.2 Selection of controls 6], while other did not [8]. A study goes even so far to An equal number of controls (n = 150) was selected suggest a reverse relationship between prolonged sitting from the ophthalmology outpatient clinic of the same posture and prevalence of LLVVs, while confirming the hospital. The same procedure (CEAP) was used to ex- impact of a prolonged standing posture of the occur- clude the presence of LLVV by the same consultant of rence of LLVV [4]. vascular surgery. In the current study, patients with past In Egypt, although venous diseases are one of the most history of thrombosis, or refused to participate in the common medical problems, there is few documented study were excluded. data about risk factors for LLVV among Egyptian popu- lation; those studies were done long time ago [14, 15]. It 2.2.3 Power analysis was essential to update data; therefore, the current study A power analysis was conducted using the Open Source was conducted to study the epidemiological, life style, Epidemiologic Statistics for Public Health (OpenEpi) [18] Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 3 of 11 to ensure that the number of identified cases will detect a half siblings); history of immobilization for 1-3 difference between cases and controls. The power analysis months; and history of leg trauma (sprains, strains, showed that enrolling 150 cases of LLVVs and 150 con- fractures, or joint dislocation). trols is capable to detect the least difference in the prob- ability of exposure between cases and controls of 14% in 2.3.1.3 Occupational factors respect to major risk factors, with an expected odds ratio of 2.2 at a power of 81.36% and confidence level of 0.95 (α  Employment status. Participants were categorized =0.05). into two categories: ever and never employed. The ever employed includes participants who are 2.3 Research tools currently employed, retired, or those with past Data was collected from cases and controls using a pre- occupations. Ever employed participants were designed and pre-tested interview questionnaire and classified according to the International Standard clinical examination. Classification of Occupations (ISCO) [21]. Duration of employment in years. 2.3.1 Interview questionnaire was conducted to collect the  Working hours/day and working hours/week. following data  Work time (daytime or shift work) Nature of work. Participants were classified into 2.3.1.1 Sociodemographic data Including participants’ white collar (performing professional, managerial, or age, sex, rural/urban residence, education attainment, administrative work), pink collar (related to and marital status. customer interaction, entertainment, sales, or other service oriented work), and blue collar (job requires 2.3.1.2 Epidemiological and life style factors manual labor) [22]. Posture at work. Spending more than half their Level of activity. Regular physical exercise lifetime working hours engaged in particular posture (exercising for 150 min of moderate intensity (standing, sitting, walking, and lifting heavy objects). aerobic physical activity throughout the week as running, walking, swimming, or spinning) [19]; 2.4 Clinical examination was conducted to collect the frequency of lifting heavy objects/day; standing following data: hours/day; sleeping hours/day; and sitting hours/day. 2.4.1 Anthropometric measurements Smoking habit. Inquiry was made into smoking Weight and height was obtained following standard pro- habit and participants were classified into current cedures, and body mass index (BMI) was computed to smoker (still smoking at least one cigarette daily for classify participants into underweight (BMI < 18 kg/m ), as long as 1 year), ex-smoker (quit smoking for at normal weight (BMI from 18.5 to < 25kg/m ), over- least 6 months prior to the date of the study), and weight (BMI from 25 to < 30kg/m ), and obese (BMI ≥ non-smoker (never smoked or smoked less than one 30 kg/m )[23]. pack per month or 20 packs in his/her whole life) [11]. Among smokers, smoking index (SI) was 2.4.2 Clinical examination of lower limbs calculated by multiplying the number of cigarettes Participants were subjected to a clinical examination of smoked per day by long life duration of smoking in the lower limbs by a consultant of vascular surgery to as- years. Smokers were classified according to their SI certain or exclude the presence of LLVVs. Cases were into light smokers (SI < 200), moderate smokers (SI classified into six categories following the CEAP system = 200-400), and heavy smokers (SI > 400) [20]. [17]including:C , no visible or palpable signs of cardio- Dietary habits and intestinal motility. Frequency vascular disease (CVD); C , telangiectasia or reticular of eating diet rich in fibers (fruit, dark green veins; C , varicose vein > 4 mm in diameter; C ,edema as 2 3 vegetables, orange vegetables, legumes, and whole a sequel of varicose vein; C , skin changes (pigmentations, grains); drinking water/day; regularity of defecation venous eczema, etc.); C , skin changes with healed ulcera- times/day; posture while defecation (sitting/squatting). tions; and C , skin changes with active ulcerations [17]. Reproductive history of married women. Gravidity; parity; and the use of oral contraceptives (OCs). 2.5 Statistical analysis Family and medical history. Positive family history The SPSS v.20 (IBM Corp. Released 2011. IBM SPSS of varices (LLVV, hemorrhoids, varicocele) among Statistics for Mac, Armonk, NY, USA) was used for data first degree relatives (parents, full siblings, or entry and analysis. Data was described using number children) and second degree relatives (grandparents, and percentages as well as mean and standard deviation. grand-children, aunts, uncles, nephews, nieces, or Univariate logistic regression analysis was done to Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 4 of 11 compute the odds ratio (OR) and the associated 95% 18.0%) resulting in an estimated risk of 1.95 (95% CI = confidence interval (95% CI) to quantify the risk of 1.13, 3.36). Smokers with LLVV were 6.27 times more LLVVs associated with the potential related factors. likely to be moderate or heavy smokers (95% CI = 1.70, Multivariate logistic regression analysis was conducted 23.16) and have a significantly higher smoking index to model LLVVs as a function of sociodemographic, (OR = 1.006; 95% CI = 1.001, 1.01) (Table 2). epidemiologic, life style, and occupational risk factors. Relative to controls, cases with LLVVs were signifi- As occupational risk factors were applicable only to ever cantly more likely to report never or infrequently con- employed participants (n = 234), two multivariate regres- suming diet rich in fibers (OR = 8.76; 95% CI = 5.16, sion models were constructed. The first one was a step- 14.86), drink less than 5 cups of water/day (OR = 14.57; wise multivariate logistic regression analysis including all 95% CI = 7.68, 27.62), and have irregular defecation participants (n = 300), in which the potential epidemio- habit (OR = 5.03; 95% CI = 3.07, 8.24). Compared with logical and life style risk factors that were significant in controls, a significantly higher percentage of cases with univariate analysis were considered in addition to age, LLVVs reported squatting posture during defecation gender, employment status, and family history of varices. (16.7% compared to 1.3%) and taking laxatives (20.7% The second model was a stepwise model limited to the compared to 4.7%). Cases were 14 times more likely to ever employed participants (n = 234) in which the afore- squat during defecation (OR = 14.80; 95% CI = 3.43, mentioned factors were considered in addition to the 63.71) and 5 times more likely to take laxatives (OR potential occupational risk factors to study their inde- = 5.32; 95% CI = 2.26, 12.51). Cases with LLVV were pendent effect. significantly more likely to be overweight or obese Significance of the obtained results was judged at the (BMI ≥ 25 kg/m ) than controls (OR = 2.57; 95% CI 5% level (α = 0.05). The explained variance of logistic = 1.09-6.08) (Table 2). regression models was determined by the Nagelkerke’s Reproductive factors were examined among married, R and Hosmer and Lemeshow goodness-of-fit test. widowed, and divorced women in the current study Significant factors in univariate analysis that include cells (cases n = 81, controls n = 75); 70.4% of women with having a count less than 5 were excluded from the LLVV reported having the disease after the first preg- multivariate analyses to avoid distortion of the model. nancy. Women with LLVV were significantly more likely to have high gravidity (≥ 4 times) (OR = 4.2; 3 Results 95% CI = 1.97, 8.95), and to have high parity (≥ 4 According to CEAP classification system, the majority of times) (OR = 7.51; 95% CI = 2.91, 19.33) than con- cases with LLVV were categorized as C2 (72.0%, n = trols. Furthermore, women with LLVV tended to use 108) and C3 (28.0%, n = 42). In addition, cases with OCs 5.20 times higher than controls (95% CI, 2.34- LLVV reported symptoms such as pain (96.0%, n = 144), 11.53). Among OCs users (cases n = 36, controls n = lower limb edema (27.3%, n = 41), while bleeding or ul- 10), the mean duration of use of OCs was signifi- cers were not reported. Among cases, 82.7% have re- cantly higher among cases with LLVV (6.91 ± 3.21) ceived conservative treatment, 24.7% reported frequent compared with controls (3.30 ± 2.83) (OR = 1.47; leg raising to alleviate symptoms, and 14% reported fre- 95% CI = 1.10, 1.97) (Table 2). quent wearing compression stoking. Regarding family and medical history, cases with LLVV Univariate analysis revealed insignificant differences in tended to have a positive family history of varices 1.73 the age and sex distribution of cases and controls. The times higher than controls (95% CI = 1.06, 2.82); they re- mean age of cases was 49.90 ± 12.09 years compared with ported positive family history of LLVV, varicocele, and 50.26 ± 10.98 years among controls (p =0.78). However, hemorrhoids (87.9%, 6.9%, and 5.2% respectively). Further- cases were 4 times more likely to report never been to more, cases with LLVV were significantly more likely to school or completed their basic education compared with have a history of leg trauma than controls (OR = 9.51; controls (OR = 4.07; 95% CI = 2.51, 6.62) (Table 1). 95% CI = 1.19, 76.03) (Table 2). Cases of LLVVs were 45.34 times more likely to report Cases and controls were comparable in respect to their lifting heavy objects (OR = 45.34; 95% CI = 6.12, 345.94). employment status (p = 0.78). Among ever employed Cases were significantly more likely to report standing for participants (cases n = 118 and controls n = 116); the more than 4 h daily (OR = 6.95; 95% CI = 4.08, 11.86) and majority of cases with LLVV were plant or machine to sleep less than 8 h per day (OR = 5.51; 95% CI = 3.02, operators (38.1%) and craft workers (27.1%), while the 10.04). No excess risk was found between cases and nei- majority of controls were technicians/associated ther controls in respect to exercising nor the number of professionals (37.1%) and service/sales workers hours spent sitting each day (Table 2). (18.1%) (Table 3). An excess of smokers was encountered among cases of Cases with LLVV were significantly more likely to LLVV compared with controls (30.0% compared with work more than 8 h/day than controls (OR = 2.82; 95% Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 5 of 11 Table 1 Sociodemographic characteristics of studied patients attending the vascular surgery and ophthalmology outpatient clinics at the Alexandria Main University Hospital, 2019, Egypt Sociodemographic Cases Controls OR (95% CI) P value characteristics (n = 150) (n = 150) No. % No. % Gender Male 68 45.3 74 49.3 1.17 (0.74, 1.84) 0.48 Female 82 54.7 76 50.7 Residence Rural 13 8.7 5 3.3 0.36 (0.12, 1.04) 0.05* Urban 137 91.3 145 96.7 Level of education Unschooling/basic education 108 72.0 58 38.7 4.07 (2.51, 6.62) >0.001*** Secondary/higher education 42 28.0 92 61.3 Marital status Never married 4 2.7 5 3.3 1 Married 111 74.0 121 80.7 1.14 (0.30, 4.37) 0.84 Widowed 19 12.7 16 10.7 1.48 (0.34, 6.47) 0.59 Divorced 16 10.7 8 5.3 2.50 (052, 11.9) 0.25 Age (years) Min-max 25-70 28-75 Mean ± SD 49.90 ± 12.09 50.26 ± 10.98 0.99 (0.98, 1.02) 0.78 SD standard deviation, OR odds ratio, CI confidence interval Reference category *p≤0.05 ***p>0.001 CI = 1.56, 5.11), and to work more than 48 h/week than factors were adjusted for gender, employment status, controls (OR = 2.53; 95% CI = 1.41, 4.53). In addition, and family history of varices. This model was able to cases with LLVV tended to have shift work 65.93 times correctly classify 87.0% of cases and 81.0% of controls higher than controls (OR = 65.93; 95% CI = 8.88, in thecurrent study(Table 4). 489.06), and to be a blue/pink collar 4 times higher than Among ever employed participants (n = 234), the controls (OR = 4.00; 95% CI = 2.28, 7.04). Regarding stepwise logistic regression model, which aimed at posture at work, cases with LLVV were significantly studying the independent effect of occupational risk more likely to stand at work for more than 4 h/working factors, revealed that standing posture at work was an day than controls (OR = 6.45; 95% CI = 3.47, 11.98), and independent predictor of LLVV (OR = 3.10; 95% CI = to sitatwork for equaltoorless than4 h/working 1.02; 9.38), in addition to other epidemiological and day than controls (OR = 5.54; 95% CI = 3.05, 10.06) life style predictors. This model was able to correctly (Table 3). classify 87.3% of the cases and 82.0% of the controls According to the stepwise logistic regression in thecurrent study(Table 5). analysis conducted among all participants (n = 300) in the current study, the independent predictors of 4 Discussion LLVVs were as follows: frequent lifting of heavy The current study identified important modifiable life objects (OR = 59.79; 95% CI = 6.01, 584.36), drinking style and occupational risk factors for the development < 5 cups of water/day (OR = 6.95; 95% CI = 2.78, of LLVV. Frequent lifting of heavy objects, drinking < 5 17.33), infrequent/no consumption of fiber-rich food cups of water/day, infrequent/no consumption of fiber- (OR = 4.27; 95% CI = 1.95, 9.37), standing more than rich food, standing more than 4 h/day, irregular 4 h per day (OR = 3.65; 95% CI = 1.63, 8.17), irregu- defecation habit, sleeping less than 8 h/day, and smoking lar defecation habit (OR = 3.34; 95% CI = 1.68, 6.60), were independent predictors of LLVV. In addition, sleeping less than 8 h per day (OR = 2.86; 95% CI = standing posture at work was found to be an independ- 1.14, 7.16), smoking (OR = 2.53; 95% CI = 1.15, ent occupational risk factor for LLVV among ever 5.58), and age (OR =1.05; 95% CI = 1.02, 1.09). Those employed participants. Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 6 of 11 Table 2 Epidemiological and life style factors associated with lower limbs varicose veins (LLVV) Epidemiological and life style factors Cases Controls OR (95% CI) P value (n = 150) (n = 150) No. % No. % Level of activity Exercising &^ Yes (regular/irregular) 27 18.0 29 19.3 1.09 (0.61, 1.95) 0.76 No 123 82.0 121 80.7 Lifting heavy objects (frequency/day) Frequent/very frequent 35 23.3 1 0.7 45.34 (6.12, 345.94) >0.001*** Occasional/rare/never^ 115 76.7 149 99.3 Standing hours/day > 4 h/day 89 59.3 26 17.3 6.95 (4.08, 11.86) >0.001*** ≤ 4 h/day^ 61 40.7 124 82.7 Sleeping hours/day < 8 h/day 62 41.3 17 11.3 5.51 (3.02, 10.04) >0.001*** ≥ 8 h/day^ 88 58.7 133 88.7 Sitting hours/day < 8 hours/day 77 51.3 72 48.0 1.14 (0.72, 1.79) 0.64 ≥ 8 hours/day 73 48.7 78 52.0 Anthropometric measurements Body mass index (BMI) Underweight and normal (BMI < 25) 8 5.3 19 12.7 2.57 (1.09, 6.08) 0.02* Overweight and obese (BMI ≥ 25) 142 94.7 131 87.3 Min-max 21.60-48.47 21.48-39.45 Mean ± SD 31.19 ± 4.71 27.68 ± 2.57 1.32 (1.22, 1.44) >0.001*** Smoking Smoking status Smoker 45 30.0 27 18.0 1.95 (1.13, 3.36) 0.01* Ex-smoker/non-smoker 105 70.0 123 82.0 Smoking intensity Light smoker 34 63.0 32 91.4 6.27 (1.70, 23.16) >0.01** Moderate/heavy smoker 20 37.0 3 8.6 Smoking index (SI) Min-max 20-500 25-300 Mean ± SD 188.5 ± 103.6 141.8 ± 73.4 1.006 (1.001, 1.01) 0.02* Dietary habits and intestinal motility Consumption of diet rich in fibers Occasional/rare/never 103 68.7 30 20.0 8.76 (5.16, 14.86) >0.001*** Frequent/very frequent 47 31.3 120 80.0 Drinking water (cups/day) ≥ 5 cups/day 136 90.7 60 40.0 14.57 (7.68, 27.62) >0.001*** ≥ 5 cups/day 14 9.3 90 60.0 Regularity of defecation Irregular 97 64.7 40 26.7 5.03 (3.07, 8.24) >0.001*** Regular 53 35.3 110 73.3 Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 7 of 11 Table 2 Epidemiological and life style factors associated with lower limbs varicose veins (LLVV) (Continued) Epidemiological and life style factors Cases Controls OR (95% CI) P value (n = 150) (n = 150) No. % No. % Posture while defecation Squatting 25 16.7 2 1.3 14.80 (3.43, 63.71) >0.001*** Sitting 125 83.3 14 98.7 Taking laxatives Yes 31 20.7 7 4.7 5.32 (2.26, 12.51) >0.001*** No 119 79.3 143 95.3 Medical and family history Family history of varices Positive family history 58 38.7 40 26.7 1.73 (1.06, 2.82) 0.02* Negative family history/not known 92 61.3 110 73.3 Immobilization for 1-3 months Yes 13 8.7 0 0.0 No 137 91.3 150 100.0 Previous leg trauma Yes 9 6.0 1 0.7 9.51 (1.19, 76.03) 0.01* No 141 94.0 149 99.3 Reproductive factors (n = 81) (n = 75) Gravidity ≥ 4 36 44.4 12 16.0 4.20 (1.97, 8.95) >0.001*** <4 45 55.6 63 84.0 Parity ≥ 4 32 39.5 6 8.0 7.51 (2.91, 19.33) >0.001*** <4 49 60.5 69 92.0 Use of OCs Yes (regular/irregular) 36 44.4 10 13.2 5.20 (2.34-11.53) >0.001*** No 45 55.6 65 86.8 Duration of OCs use (years) < 5 years 5 13.9 7 70.0 14.46 (2.77, 75.3) 0.001** ≥ 5 years 31 86.1 3 30.0 Min-max 1-12 1-10 Mean ± SD 6.91 ± 3.21 3.30 ± 2.83 1.47 (1.10, 1.97) >0.01** Abbreviations: SI smoking index, SD standard deviation, OR odds ratio, CI confidence interval, OCs oral contraceptive pills Reference category Among smokers (cases n = 54, controls n = 35), light smokers (SI < 200), moderate/heavy smokers (SI ≥ 200) Where frequent is ≥ 5 times per week Regular exercise defined as 150 min of moderate intensity aerobic physical activity per week Number of women excluding single women (cases n = 81, controls n = 75) Number of women using OCs (cases n = 36, controls n = 10) *p≤0.05 **p>0.01 ***p>0.001 Age was found to be an independent predictor of between increasing age and varicose veins [10–12, 24, LLVV in the current study; an effect that was masked by 25], no sex-dependent difference in LLVV, and a nega- other factors in univariate analysis, whereas gender and tive relation between family history and varicose veins family history of varices were not associated with risk of [12]. On the contrary, in Ziegler et al. study, age was not LLVV. Similarly, several studies revealed an association a risk factor for varicose veins [26]. Also, some studies Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 8 of 11 Table 3 Occupational factors associated with lower limbs varicose veins (LLVV) Occupational factors Cases Controls OR (95% CI) P value No. % No. % Employment status (n = 150) (n = 150) Never employed 32 21.3 34 22.7 1.08 (0.62, 1.86) 0.78 Ever employed (currently/previously) 118 78.7 116 77.3 Among ever employed (n = 118) (n = 116) Duration of employment (years) Min-max 2-50 2-50 Mean± SD 23.55 ± 13.70 24.50 ± 14.09 0.99 (0.98, 1.01) 0.60 ISCO classification Professionals 3 2.5 22 19.0 1 Technicians and associated professionals 24 20.3 43 37.1 0.27 (0.01, 4.00) 0.34 Service and sales workers 10 8.5 21 18.1 1.11 (0.09, 12.96) 0.93 Skilled agricultural and fishery workers 3 2.5 2 1.7 0.95 (0.07, 11.78) 0.97 Craft and related trade workers 32 27.1 8 6.9 3.00 (0.15, 59.89) 0.47 Plant and machine operators 45 38.1 18 15.5 8.00 (0.64, 99.66) 0.10 Elementary occupations 1 0.8 2 1.7 5.00 (0.42, 58.63) 0.20 Working hours/day Working > 8 h/day 47 39.8 22 19.0 2.82 (1.56, 5.11) >0.001*** Working ≤ 8 h/day 71 60.2 94 81.0 Working hours/week Working > 48 h/week 47 39.8 24 20.7 2.53 (1.41, 4.53) >0.01** Working ≤ 48 h/week 71 60.2 92 79.3 Work time Day work 75 63.6 115 99.1 65.93 (8.8, 489.1) 0.001** Shift work 43 36.4 1 0.9 Nature of work Blue/pink collar 91 77.1 53 45.7 4.00 (2.28, 7.04) >0.001*** White collar 27 22.9 63 54.3 Posture at work Standing 66 55.9 18 15.5 6.91 (3.71, 12.84) >0.001*** Sitting 52 44.1 98 84.5 Sitting hours/working day Sitting ≤ 4 h/ working day 65 55.1 21 18.1 5.54 (3.05, 10.06) >0.001*** Sitting < 4 h/ working day 53 44.9 95 81.9 Standing hours/working day Standing <4 h/working day 64 54.2 18 15.5 6.45 (3.47, 11.98) >0.001*** Standing >4 h/working day 54 45.8 98 84.5 Lifting heavy objects (hours/working day) ≥ 2 h/working day 7 5.9 1 0.9 7.25 (0.87, 59.90) 0.06 < 2 h/working day 111 94.1 115 99.1 ISCO International Standard Classification of Occupations, SD standard deviation, CI confidence interval, OR odds ratio Reference category Number of participants currently/previously employed (cases = 118, controls = 116) **p> 0.01 ***p>0.001 Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 9 of 11 reported association between positive family history and In the current study, never going to school or obtain- varicose veins [6, 27]; the results of studies must be ing only basic education, which is a proxy for low socio- interpreted with caution, as varicose veins are a common economic status, was significantly associated with LLVV. problem, thus, a large proportion of study subjects This could be explained by the fact that level of would report a positive family history. education determines the nature of occupation (blue/ Besides, some studies revealed an association between pink collar vs white collar) which directly affects the de- female gender and varicose veins [10, 11, 24, 26]. Differ- velopment of varices. Among ever employed participants ent distribution of reproductive risk factors among in the current study, 65% of cases with LLVV were plant women in different studies might lead to diverse results. and machine operators and craft workers, while profes- Gravidity, parity, and use of OCs could independently sionals represented 2.5% of cases. Likewise, in other increase the risk of LLVV among women compared with studies, the majority of cases were manual laborers, men, in some studies. Different findings may also be due farmers, house wives, nurses, utility workers, and to different study designs, sample size, and population cleaners [24, 26, 29]. This supports the observation that characteristics. occupation involving violent muscular activity are at The current study as well as previous studies reported high risk for developing varicose veins. Hot and humid the higher risk of LLVVs associated with high parity [4, workplace conditions and socioeconomic may also be 6, 12, 25] and the use of OCs [28]. Beebe-Dimmer et al. implicated [26]. [4] attributed the adverse effects of pregnancy to the in- Among ever employed participants in the current crease in blood volume as well as the increase in intra- study, standing posture at work was found to be an inde- abdominal pressure and central venous return resulting pendent predictor of LLVV. Most studies indicate that from fetal growth and weight gain; the elevated pressure working in a position resulting in protracted orthostasis can result in valve failure and progression of varices. may increase the prevalence and severity of LLVV; a sig- Also, the increase in the levels of relaxin, estrogen, and nificantly higher prevalence of varicose veins was found progesterone during pregnancy play a role in the devel- in employees working in a prolonged standing posture opment of varices. In contrast, other studies did not [6, 24, 26, 30]; while the lowest prevalence was found in support the association of LLVVS with pregnancy [28] medical technician assistants, secretaries, and scientific or the use of hormonal contraceptives [12, 26]. The vari- staff, since these professions have the shortest mean pe- ation in the effect of OCs between this study and that of riods of standing at work [26]. Yun et al. study [12] could be attributed to the difference Regarding physical activity, frequent lifting of heavy in the distribution of reproductive risk factors; all of the objects, standing for more than 4 h/day, and sleeping for women in their study were working nurses and most of less than 8 h/day, were found to be independent predic- them were unmarried. In the current research, the small tors of LLVV in the present study and in Tabatabaeifar number of ever married women and those who ever et al. study [25]. Whereas no relation was found between used hormonal contraceptives precluded studying the in- regular physical exercise and the development of LLVV dependent effect of reproductive factors. in the current study and in Yun et al. study [12]. On the Table 4 Stepwise logistic regression analysis of the independent predictors of lower limb varicose veins (LLVV) among all participants (n =300) Independent predictors Coefficient Adjusted OR 95% CI P value Age 0.05 1.05 (1.02, 1.09) < 0.01** Smoking 0.93 2.53 (1.15, 5.58) 0.02* Infrequent/no consumption of fiber-rich food 1.45 4.27 (1.95, 9.37) < 0.001*** Drinking < 5 cups of water/day 1.94 6.95 (2.78, 17.33) < 0.001*** Irregular defecation habit 1.20 3.34 (1.68, 6.60) < 0.01** Frequent lifting of heavy objects/day 4.09 59.79 (6.01, 584.36) < 0.001*** Standing > 4 h/day 1.29 3.65 (1.63, 8.17) < 0.01** Sleeping < 8 h/day 1.05 2.86 (1.14, 7.16) 0.02* Abbreviations: OR odds ratio, CI confidence interval 2 2 2 2 Model X = 200.91 (p < 0.001); Nagelkerke’sR = 0.65; Cox and Snell R = 0.48; Hosmer and Lemeshow X = 5.57 (p=0.69) OR adjusted for gender, employment status, family history of varices, and potential life style risk factors significant in univariate analysis (posture during defecation, taking laxatives, and body mass index) Occupational risk factors and significant factors that include cells having a count less than 5 were excluded from the regression model *p<0.05 **p<0.01 ***p<0.001 Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 10 of 11 Table 5 Stepwise logistic regression analysis of the independent predictors of lower limb varicose veins (LLVV) among ever employed participants (n = 234) Independent predictors Coefficient Adjusted OR 95% CI P value Standing posture at work 1.13 3.10 (1.02, 9.38) 0.04* Age 0.06 1.06 (1.02, 1.10) <0.01** Frequent lifting of heavy objects/day 3.63 37.59 (3.52, 400.86) <0.01** Standing > 4 h/day 1.26 3.52 (1.20, 10.33) 0.02* Infrequent/no consumption of fiber-rich food 1.45 4.24 (1.70, 10.62) <0.01** Drinking < 5 cups of water/day 2.24 9.42 (3.43, 25.89) <0.001*** Irregular defecation habit 1.87 6.46 (2.73, 15.27) <0.001*** Taking laxatives −1.63 0.20 (0.05, 0.08) 0.02* Abbreviations: OR odds ratio, CI confidence interval 2 2 2 2 Model X = 157.19 (p < 0.001); Nagelkerke’sR = 0.65; Cox and Snell R = 0.48; Hosmer and Lemeshow X = 10.48 (p = 0.23) OR adjusted for gender, family history of varices, and potential occupational and life style risk factors significant in univariate analysis (working hours per week, nature of work, standing hours/working day, sitting hours/working day, body mass index, smoking, posture during defecation, and sleeping hours/day) Significant factors that include cells having a count less than 5 were excluded from the regression model *p<0.05 **p<0.01 ***p<0.001 contrary, in other studies, regular exercising was found risk [30], and smoking pack-years significantly increases to be a protective factor [10, 24]. The difference in find- the odds of varicose veins by 1.12 [10]. It has been hy- ings might be due to different definitions of the regular pothesized that smoking leads to hypoxia, production of exercising term in studies. proinflammatory factors within the vessel wall, biochem- As regard dietary habits and intestinal motility, low ical modifications on the venous endothelium that dietary fiber intake, drinking less than 5 cups of water/ increases the vasomotor tonicity in the venous walls, and day, and irregular defecation were independent predic- lengthening of scarring time which influence the trophic tors of LLVV in the present study and in other studies disorders associated with LLVV [30]. [4, 24, 31] which proposed that constipation and in- Few participants in the present study had a history of creased intra-abdominal pressure contributed to ob- leg trauma and long immobilization which was signifi- struction of venous return. People usually take laxatives cantly associated with LLVV in accordance with Abelyan to regulate their irregular bowel movement; this explains et al. study [10]. In contrast, Yun et al. study found no the change in findings in the present study, where taking significant association between leg injury and varicose laxatives was a risk factor for LLVV in univariate ana- veins [12]. The independent effect of those variables calls lysis, while in multivariate analysis, it had a protective for further studies on a larger sample. effect. Overweight or obesity (BMI ≥ 25) was not a predictor 4.1 Limitations of the study of LLVV in the current study. In Seidel et al. study, the The current case control study (retrospective study) might association between obesity and varicose veins was be subjected to recall bias; cases with LLVVs would prob- found in women but not in men [8]; however, in his ably be more aware of the past medical and family events study, there was an observed gender difference, besides, related to their conditions. Additionally, the relatively parity may act as a confounding factor due to the fact small number of ever married women limited studying the that parous women tend to have high average body independent effect of reproductive factors. weight [8]. In literature, the data on correlation between obesity and varicose veins is controversial; and whether it has an independent or an aggravating effect on the de- 5 Conclusion velopment of varicose veins is still debatable [7]. The present study highlighted seven modifiable inde- Smoking was an independent predictor of LLVV in pendent predictors of LLVV mostly related to the life the current study; smokers had 2.53 times greater risk to style. These findings provide a foundation for planning develop LLVV. Moreover, smoking intensity was signifi- an evidence-based low-cost strategy for prevention of cantly associated with LLVV; moderate/heavy smokers LLVV among Egyptian population. Future studies are had 6.27 times greater risk to develop LLVV. Similarly, recommended to examine cause-effect relationship, and in a multicenter review and in other studies, the propor- evaluate independent effect of reproductive factors on tion of varicose veins cases with history of smoking was the development of LLVV. 19.4%, and 45.6% [29], smokers had 1.8 times greater Elamrawy et al. Journal of the Egyptian Public Health Association (2021) 96:19 Page 11 of 11 Abbreviations 6. Robertson L, Evans C, Fowkes F. Epidemiology of chronic venous disease. BMI: Body mass index; CEAP: Clinical, Etiologic, Anatomic, Pathophysiologic; Phlebology. 2008;23(3):103–11. CI: Confidence interval; CVD: Chronic venous disease; ISCO: International 7. Hirai MKN, Nakayama R. Prevalence and risk factors of varicose veins in Standard Classification of Occupations; LLVV: Lower limb varicose veins; Japanese women. Angiology. 1990;41(3):228–32. OCs: Oral contraceptive pills; OR: Odds ratio; SD: Standard deviation; 8. Seidel AC, Belczak CE, Campos MB, Campos RB, Harada DS. The impact of SI: Smoking index obesity on venous insufficiency. Phlebology. 2015;30(7):475–80. 9. DA Brand FN, Abbott RD. The epidemiology of varicose veins: the Framingham study. Am J Prev Med. 1988;4(2):96–101. Acknowledgements 10. Abelyan G, Abrahamyan L, Yenokyan G. A case-control study of risk factors Not applicable. of chronic venous ulceration in patients with varicose veins. Phlebology. 2018;33(1):60–7. Authors’ contributions 11. Lee AJ, Evans CJ, Allan PL, Ruckley CV, Fowkes FGR. Lifestyle factors and the risk SE generated the research idea, and designed the work. ID designed the of varicose veins: Edinburgh Vein Study. J Clin Epidemiol. 2003;56(2):171–9. work, and revised the research article (manuscript) for submission. SM 12. Yun MJ, Kim YK, Kang DM, Kim JE, Ha WC, Ky J, et al. A study on prevalence conducted the clinical examination of the lower limbs for all participants. NE and risk factors for varicose veins in nurses at a university hospital. Safety carried out data analysis and interpretation, and drafted the research article. Health Work. 2018;9(1):79–83. NA collected the data and revised the manuscript for submission. All authors 13. Müller-Bühl U, Leutgeb R, Engeser P, Achankeng EN, Szecsenyi J, Laux G. have read and approved the manuscript. Varicose veins are a risk factor for deep venous thrombosis in general practice patients. Vasa. 2012;41(5):360–5. Funding 14. Darwish I. Some epidemiological features of cases having lower limb Authors report that there was no funding source for the work or the varicose veins attending the main university hospital in Alexandria. Master preparation of the tools. Thesis, Faculty of Medicine: Alexandria University; 1987. 15. Mekky S, Schilling R, Walford J. Varicose veins in women cotton workers. An Availability of data and materials epidemiological study in England and Egypt. Br Med J. 1969;2(5657):591–5. Data and materials are available on reasonable request. Confidentiality and 16. Piazza G. Varicose veins. Circulation. 2014;130(7):582–7. security of data and materials were insured through all stages of the study. 17. Eklöf B. CEAP classification and implications for investigations. Acta Chir Belg. 2006;106(6):654–8. Declarations 18. Dean AG, Sullivan KM, Soe MM. OpenEpi: open source epidemiologic statistics for public health, Version. www.OpenEpi.com, 2013 Ethics approval and consent to participate 19. World Health Organization. Global strategy on diet, physical activity and The study was approved by the Research Ethics Committee of AFM, health. WHO. [Internet] 2018. Available from: http://www/who/int/ University of Alexandria (the committee’s reference number: not applicable). dietphysicalactivity/pa/en An informed written consent was obtained from each participant at the 20. Lee Y, Shin M, Kweon S, Choi J, Rhee J, Ahn H, et al. Cumulative smoking beginning of the study after explanation of the objectives of the study, exposure, duration of smoking cessation, and peripheral arterial disease in procedures, and types of information to be obtained. middle-aged and older Korean men. BMC Public Health. 2011;11(1):94. 21. International Labour Organization Office. The International Standard Classification of Occupations: introduction to occupational classifications. Consent for publication ILO. [Internet] 2018. [cited in 2020, April 2]. Available from: http://www.ilo. Not applicable. org/public/english/bureau/stat/isco/intro.htm. 22. Holland PJHR, Steen J. Human resource strategies and organizational Competing interests structures for managing gold-collar workers. J Eur Ind Train. 2002;26(2-4):80. Authors declare no conflicts of interest. The research was not supported by 23. Papadakis MA, Rabow MW. CURRENT medical diagnosis and treatment. Mc any commercial source; no financial relationships with any organizations that Graw Hill Education Lange 2018;57. might have an interest in the submitted work. 24. Sharif Nia H, Chan YH, Haghdoost AA, Soleimani MA, Beheshti Z, Bahrami N. Varicose veins of the legs among nurses: occupational and demographic Author details characteristics. Int J Nurs Pract. 2015;21(3):313–20. Public Health, Preventive and Social Medicine, Community Medicine 25. Tabatabaeifar S, Frost P, Andersen JH, Jensen LD, Thomsen JF, Svendsen Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt. SW. Varicose veins in the lower extremities in relation to occupational Vascular Surgery Department, Faculty of Medicine, Alexandria University, mechanical exposures: a longitudinal study. Occup Environ Med. 2015;72(5): Alexandria, Egypt. Industrial Medicine and Occupational Health, Community 330–7. Medicine Department, Faculty of Medicine, Alexandria University, 26. Ziegler SEG, Stoger R, Machula J, Rudiger H. High prevalence of chronic Champolion Street, El Azareeta, Alexandria 21131, Egypt. Ministry of Health, venous disease in hospital employees. Wien. Klin. Wschr. 2003;575:9. Austria. Alexandria, Egypt. 27. Bahk JW, Kim H, Jung-Choi K, Jung MC, Lee I. Relationship between prolonged standing and symptoms of varicose veins and nocturnal leg Received: 26 August 2020 Accepted: 11 May 2021 cramps among women and men. Ergonomics. 2012;55(2):133–9. 28. Robertson L, Evans C, Lee A, Allan P, Ruckley C, Fowkes F. Incidence and risk factors for venous reflux in the general population: Edinburgh Vein Study. References Eur J Vasc Endovasc Surg. 2014;48(2):208–14. 1. Davies AH. The seriousness of chronic venous disease: a review of real- 29. Joseph N, Abhishai B, Thouseef MF, Devi U, Abna A, Juneja I. A multicenter world evidence. Adv Ther. 2019;36(S1):5–12. review of epidemiology and management of varicose veins for national 2. Gloviczki P, Comerota AJ, Dalsing MC, Eklof BG, Gillespie DL, Gloviczki ML, guidance. Ann Med Surg. 2016;8:21–7. et al. The care of patients with varicose veins and associated chronic 30. Gourgou S, Dedieu F, Sancho-Garnier H. Lower limb venous insufficiency venous diseases: clinical practice guidelines of the Society for Vascular and tobacco smoking: a case-control study. Am J Epidemiol. 2002;155(11): Surgery and the American Venous Forum. J Vasc Surg. 2011;53(5):S2–48. 1007–15. 3. Raetz J, Wilson M, Collins K. Varicose veins: diagnosis and treatment. Am 31. Lee AJ, Evans CJ, Hau CM, Fowkes FG. Fiber intake, constipation, and risk of Fam Physician. 2019;99(11):682–8. varicose veins in the general population: Edinburgh Vein Study. J Clin 4. Beebe-Dimmer JL, Pfeifer JR, Engle JS, Schottenfeld D. The epidemiology of Epidemiol. 2001;54(4):423–9. chronic venous insufficiency and varicose veins. Ann Epidemiol. 2005;15(3):175–84. 5. Aly SG, Wahdan MM, Ahmed DH, Ibrahim EF. Abd El- Hamid DM. Varicose veins: prevalence and associated risk factors among women of childbearing Publisher’sNote age attending a primary health care unit in Cairo, Egypt. Egypt Fam Med J. Springer Nature remains neutral with regard to jurisdictional claims in 2020;4(1):58–75. published maps and institutional affiliations.

Journal

Journal of the Egyptian Public Health AssociationSpringer Journals

Published: Jul 6, 2021

Keywords: Epidemiological factors; Life style; Occupational factors; Varicose veins

References