TY - JOUR
AU - Beral,, Valerie
AB - Abstract Background To determine whether intake of animal products was associated with a reduced risk of stroke mortality in a large-scale population-based cohort in Japan. Methods A self-administered questionnaire, including questions on dietary habits, was mailed to the members of the Life Span Study, a cohort of people exposed and non-exposed to atomic bomb radiation, who were alive as of 1 September 1979. Animal products included frequency intake of beef/pork, chicken, ham/sausage, milk, dairy products, eggs, fish, and broiled fish. Responses were obtained from 40 349 people (72%): 15 350 men (mean age 54 years) and 24 999 women (mean age 58 years). The subjects were followed for 16 years, and deaths were ascertained by linkage to the nationwide family registration system of Japan. The associations between diet and stroke mortality were examined using a Cox proportional hazard model. Results During the follow-up period, 1462 stroke deaths occurred. Four animal products comprising eggs, dairy products, fish, and broiled fish were independently associated with a decreased risk of stroke mortality; while beef/pork, chicken, ham/ sausage, and milk consumption were not associated with stroke death. A composite measure of eggs, dairy products, fish, and broiled fish intake was calculated, and the highest tertile was significantly inversely associated with total stroke mortality (Hazards Ratio [HR] = 0.80, 95% CI: 0.68, 0.93) compared with the lowest tertile. The protective effect of animal product intake on total stroke death was largely confined to intracerebral haemorrhage death; the RH of intracerebral haemorrhage death for the highest tertile of consumption was 0.72 (95% CI: 0.53–0.98) compared with the lowest tertile; animal products intake was not related to cerebral infarction mortality (HR = 0.84; 95% CI: 0.67–1.06). Conclusions Intake of animal products such as eggs, dairy products, and fish may be protective against intracerebral haemorrhage, but is not related to cerebral infarction mortality. Cerebrovascular disease, animal products, diet, mortality, longitudinal study, Japan Stroke was the leading cause of death in Japan for the 30-year period ending in 1980 and is currently the third, following cancer and coronary heart disease. In the 1960s, the age-adjusted mortality rate from stroke in Japan was twice that in Western countries,1 although international comparison might be difficult due to different diagnostic criteria and methodology used. During that period, in Japan, intracerebral haemorrhage was the predominant sub-type; this has been a common feature of East Asian countries.2 Since the mid 1960s, there has been a steady and dramatic reduction in the stroke mortality rate,3 declining by 30% in men and 20% in women between 1965 and 2000.4 Recent data show that the age-standardized stroke mortality rate in Japan (56.7 per 100 000 population) is now similar to that in Germany (52.4) and the UK (51.8), although is still higher than that in the US (34.8);5 death rates being standardized to the WHO World Standard Population. Interestingly, while the decline in total stroke mortality largely represented that of intracerebral haemorrhage subtype,4 cerebral infarction rates increased nearly fivefold in men and threefold in women between 1951 and 1984.4 Since 1975, the cerebral infarction mortality rate is higher than that of intracerebral haemorrhage and is now the predominant subtype. This indicates that intracerebral haemorrhage and cerebral infarction are affected differently by lifestyle factors. Available data to date suggest that, other than age and hypertension, cerebral haemorrhage and infarction do not share the same risk factors.6 Suggested risk factors for intracerebral haemorrhage include a history of coronary artery disease, low total cholesterol level, and a low intake of animal protein and fat.7,8 High alcohol intake, high physical activity at work, and poor home heating may also be associated with stroke mortality, and together these three factors may contribute as much as high systolic blood pressure alone.1 Risk factors for cerebral infarction include atrial fibrillation, smoking, high total cholesterol levels, low high-density lipoprotein cholesterol levels, and possibly, a low fish intake.9,10 It has been suggested that the observed change in stroke mortality rate may be explained by both improvements in preventive and medical care, and the acceleration of the ‘westernization’ or ‘modernization’ of Japanese lifestyles from the end of World War II.11,12 Nationwide community-based hypertension control programmes, nutrition education campaigns to reduce salt intake, and improvements in hypotensive agents were clearly associated with a dramatic decline in average blood pressure levels and subsequent stroke incidence.13,14 In addition, the extended period of strong economic growth from 1960 to 1975 brought about a series of socioeconomic changes including better working conditions, the mechanization of farming, improvements in household heating systems, changes in dietary habits, and developments of refrigeration and marketing.15 Westernization of the diet included an increased consumption of meat, milk, eggs, dairy products, and fruit.3,16 A previous study conducted in the whole of Japan between 1965 and 1982 among 223 170 men and women suggested that an increased consumption of animal products might be protective against cerebrovascular disease mortality.17 The aim of the present study is to examine whether a high intake of animal products estimated from a food frequency questionnaire (FFQ) is associated with a subsequent reduction in total stroke mortality, and whether the associations are different between the two main subtypes intracerebral haemorrhage and cerebral infarction, using a cohort of more than 55 000 Japanese atomic bomb-survivors men and women living in the community. Methods Study subjects The Life Span Study (LSS) cohort originally comprised 120 321 Hiroshima and Nagasaki atomic bomb survivors and their non-exposed controls. Since 1950, it has been followed up by the Atomic Bomb Casualty Commission (ABCC), later the Radiation Effects Research Foundation (RERF).18 A self-administered questionnaire including items on dietary habits was mailed to 55 650 people who were alive as of 1 September 1979.19 The mail survey was completed in January 1980 for men, and in February 1981 for women. Responses were obtained from 40 349 people (72.5%). After excluding prevalent cases of cancer (n = 476), self-reported cases of stroke (n = 392), ischaemic heart disease (n = 2250), and both stroke and ischaemic heart disease (n = 101), the study population consisted of 37 130 people, of whom 14 209 were men and 22 921 were women. The mean age of the subjects was 56 years (range: 34–103). Ascertainment of dietary habits The questionnaire included items on age, anthropometric measurements, smoking, and other lifestyle factors, and a 22-item FFQ. Details on the FFQ have been reported elsewhere.20 The FFQ included questions on the consumption frequency of nine animal products: beef and pork, pork products such as ham/sausage, chicken, milk, eggs, dairy products (butter and cheese, excluding margarine), fish excluding broiled and dry fish, broiled fish, and dry fish. Subjects were asked to state how frequently they ate each food item, based on four categories: ‘never’, ‘≤once/week’, ‘2–4 times/week’, and ‘almost daily’. A previous validation study found the mean daily intakes of animal foods estimated from the FFQ to be significantly associated with intake as estimated from a 24-hour dietary record, with Spearman correlation coefficients ranging from 0.17 to 0.32 across categories of intake. However, intake of ‘dry fish’ from the FFQ was not correlated with intake from the 24-hour dietary record, and was therefore excluded from the present analysis.20 First, the relationship between stroke mortality and each animal product intake was analysed separately. The FFQ validation study showed that the mean intake in weight of a food item that was recorded as missing on the questionnaire was similar to that of the ‘never’, or ‘≤once/week’ frequencies. We concluded that those who did not report their intake in the FFQ scarcely or never ate the food.20 We therefore grouped those with missing values together with the lowest frequency category, and were thus able to include the entire study population in the analysis. Second, mortality risks were related to a composite variable of total intake of animal products and of their subsets. First, the intake of each food product was categorized into three groups: missing, never and ≤once/week (scored as 0), 2–4 times/week (scored as 1), and almost daily (scored as 2). All animal product intake was then defined as the sum of scores (0–1–2) of beef and pork, chicken, pork products, milk, egg, dairy products, fish excluding broiled/dry fish, and broiled fish. Another composite variable included the animal products significantly inversely associated with stroke mortality. Fish product intake was defined as the sum of scores of fish excluding broiled/dry fish, and broiled fish. The three composite variables were then categorized into three levels of consumption—low, moderate, and high—with the number of subjects in each category equally distributed. The mean daily intake of animal foods in each category was estimated by multiplying the frequency of consumption from the FFQ with an average portion size according to the mean intake derived the 24-hour diaries. Follow-up and ascertainment of stroke death cases Stroke death cases were ascertained by linkage to the nationwide family registration system of Japan.18,21 Copies of death certificates are regularly obtained by RERF for all deceased LSS cohort members, and trained coders enter the appropriate codes into the database. The ascertainment is virtually complete, since the death certificates are available as long as the subjects reside within Japan, and the number of emigrants is small. Causes of deaths were coded according to the International Classification of Diseases codes.22 Follow-up was started on 1 January 1980 for men and 1 February 1981 for women, and continued until the date of stroke death, death from other causes, or 31 December 1996, whichever came earliest. Statistical analysis The association between animal product intake and stroke mortality was examined using a Cox proportional hazard model, and hypothesis tests and CI were based on Wald statistics. Age was the primary time scale in all analyses and baseline rates were stratified by sex and birth cohort. All multivariate analyses were adjusted for possible confounding variables: smoking status (never, past, and current), alcohol-drinking status (never, past, and current), body mass index (BMI) calculated from the self-reported height and weight (<19, 19–<22, 22–<25, and 25+ kg/m2), education level (junior high school or lower, high school, and junior college/university or higher), self-reported histories (yes, no) of diabetes mellitus or hypertension, radiation dose (continuous variable in mSv), and city (Hiroshima, Nagasaki). The analyses were carried out using the SAS software version 8.23 Results During the observation period, 1462 deaths from stroke were identified, including 655 cases (45%) attributed to cerebral infarction, 354 (24%) attributed to intracerebral haemorrhage, 116 (8%) attributed to subarachnoid haemorrhage, and 337 (23%) attributed to other cerebrovascular disease. The percentage distributions of cerebrovascular disease deaths were similar between the sexes (Table 1). The frequency distribution of animal product intakes is shown in Table 2. More than half of the subjects consumed beef and pork, fish, or eggs at least twice each week. In contrast, half of the subjects consumed broiled fish once or less each week, and about 40% had chicken and pork products once or less a week. One-fifth of the study population indicated ‘never’ as the frequency for eating dairy products. The association between non-dietary factors and mortality from total stroke, intracerebral haemorrhage, and cerebral infarction are shown in Table 3. Current smoking was significantly associated with an increased risk of total stroke, intracerebral haemorrhage, and infarction. Past alcohol drinkers also had a significantly increased risk of total stroke and intracerebral haemorrhage, although current drinkers did not. There was a U-shaped association between BMI and stroke mortality, with a BMI of 22–25 kg/m2 having the lowest risk of all types of stroke. A high education was associated with reduced mortality from all types of stroke, although these associations were not statistically significant. As expected, a previous history of diabetes and hypertension were also significantly related to an increased risk of total stroke, intracerebral haemorrhage, and cerebral infarction mortality. The association between stroke mortality and each animal product is presented in Table 4. Daily intake of each animal product was associated with a decrease risk of total stroke, except beef and pork intakes which were not associated, and chicken intake which was positively associated with the risk of stroke mortality. Adjustment for each other animal product intake did not alter the risks; egg, dairy products, fish, and broiled fish remained associated with a decrease risk of stroke mortality. The associations between composite scores of animal intake and stroke mortality and the two subtypes are shown in Table 5. Intake of all animal products was associated with a 12% (95% CI: 23%, 0%) reduction in total stroke death, and a significant 24% (95% CI: 42%, 1%) reduction in the risk of intracerebral haemorrhage mortality in the highest tertile as compared with the lowest tertile (Table 5). The association between total animal product intake and intracerebral haemorrhage mortality also showed a significant linear dose–response relationship; additional adjustment for fruit and vegetables consumption, suggested protective factors of stroke, did not materially alter the findings (fruit and vegetables adjusted stroke mortality HR = 0.96 [95% CI: 0.84, 1.09], intracerebral haemorrhage HR = 0.81 [95% CI: 0.62, 1.06]). The risk of cerebral infarction death was not associated with animal product consumption. A composite variable comprising animal products that were found to be significantly inversely associated with stroke mortality, as shown in Table 4, was calculated by summing of scores of egg, dairy products, fish, and broiled fish products, in a manner identical to that for total animal product intake. Intake of significant animal products was associated with a significant 20% (95% CI: 32%, 7%) reduction in total stroke death, and a significant 28% (95% CI: 47%, 2%) reduction in the risk of intracerebral haemorrhage mortality in the highest tertile compared with the lowest (Table 5). Intake of total fish products was also associated with a significant 15% (95% CI: 25%, 2%) reduction in total stroke death, and a significant 30% (95% CI: 46%, 8%) reduction in the risk of intracerebral haemorrhage mortality in the highest tertile compared with the lowest (Table 5). Neither total animal products, nor significant animal products, or total fish products were significantly associated with a reduction in cerebral infarction death. These findings were not affected by adjustment for fruit and vegetables consumption: significant animal products stroke mortality HR = 0.86 (95% CI: 0.74, 1.01), intracerebral haemorrhage HR = 0.79 (95% CI: 0.58, 1.08); total fish products stroke mortality HR = 0.96 (95% CI: 0.84, 1.10), intracerebral haemorrhage HR = 0.81 (95% CI: 0.62, 1.05). Discussion In this large-scale population-based cohort study in Japan, consumption of egg, dairy products, and fish was significantly and inversely associated with the risk of all stroke mortality. However, considering the pathological and aetiological differences of intracerebral haemorrhage and cerebral infarction, it is important to examine these subtypes separately.6 Animal product consumption was negatively associated with intracerebral haemorrhage mortality, but not related to cerebral infarction death. The analysis of the health effects of a vegetarian diet is of interest in the investigation of the health effects of meat or animal products intake. Unfortunately, the data on the rate of stroke mortality among vegans (people who consume no animal products) compared with meat-eaters is sparse and further research is clearly needed to determine whether these individuals are at an increased risk. Several studies have shown vegetarians, who consume animal protein in the form of milk, egg, and dairy products, to not have an elevated rate of stroke mortality compared with non-vegetarians,24–26 despite their lower levels of cholesterol.27 In Japan, consumption of animal products has generally increased since World War II. Intakes of fish/shellfish, eggs, milk, and meats increased until 1970–1975 and have been constant thereafter, whilst the intake of dairy products has been constantly increasing (Figure 1).28,29 Nevertheless, the consumption in Japan is lower than that of Western countries. During the study period, the proportion of energy from animal products in Japan represented half of the estimated energy intake compared with that in Western countries (Japan 18%, UK 37%, USA 36%).30 Two longitudinal studies carried out in Japan in the 1970s also found an inverse association between the intake of animal products and stroke incidence or mortality, although these associations were weak and not statistically significant.31,32 Recently, Kinjo et al. reported similar results to those in this study, in a Japanese cohort of more than 220 000 subjects followed from 1966 to 1981.17 Intakes of ‘dairy milk’, ‘meat’, and ‘fish’ were each significantly, inversely associated with mortality risk of intracerebral haemorrhage. Dairy milk and meat were also related to a decreased risk of cerebral infarction, but the risk reductions were smaller than for intracerebral haemorrhage, and fish consumption was not associated with cerebral infarction. After Japan’s recent high economic growth period (1975), serum cholesterol levels in the Japanese population have been increasing along with the intakes of animal products.33–35 The association between serum cholesterol concentrations and the risk of stroke mortality has been examined extensively. Hypocholesterolaemia is consistently associated with an increased risk of intracerebral haemorrhage mortality among Japanese living in Japan,15,36–39 Japanese Americans,40,41 and Caucasians.42,43 A low cholesterol level, associated with severe hypertension, is thought to involve a weakening of the endothelium of cerebral arteries, and could, in part, explain the observed protective association of animal products consumption with intracerebral haemorrhage.44 Previous findings from prospective studies on the relationship between serum cholesterol levels and cerebral infarction are inconsistent: low serum cholesterol level has been associated with a decreased risk,42,45 with no association,14,15,37,38,40 and with an increased risk.13,44,46 Cerebral infarction can be classified into two types according to the size and location of responsible arteries: (1) cervical and cortical or large arteries, and (2) penetrating or small arteries.47 Recent studies suggest that the intake of animal products and related factors may have different effects on these two types of cerebral infarction. Pathogenesis of large arteries infarction involves high cholesterol levels and atherogenesis, while pathogenesis of small arteries infarction is related to a weakening of the smaller arteries endothelium due to low serum cholesterol levels associated with sustained mild or moderate hypertension.44 In a male cohort in the US, fat intake predisposed to atherosclerosis in the larger vessels, but was protectively associated with the integrity of the smaller intracranial vessels.46 An autopsy study of members of the Honolulu Heart Program showed that protein and fat from animal sources were not associated with atherosclerosis in the small cerebral vessels, while they increased the risk of atherosclerosis in large arteries.48 Infarction in small arteries used to be the most prevalent sub-type of cerebral infarction in Japan before the 1970s, opposite to that of Caucasians.44,49,50 However, concomitant with the rise in serum cholesterol levels, cerebral infarction in the region of the large arteries is increasing.47 This may suggest that animal products will not remain a somewhat protective factor of cerebral infarction in Japan, but become a risk factor of infarction through their atherogenic effects on large arteries. However, among the present population, no protective or risk factor association was observed. Another factor that may complicate the interpretation of the results for cerebral infarction is the difference in fat composition from meat and fish. Meat products are rich in saturated fatty acids, thought to be a risk factor for cerebral infarction via its atherogenecity. Conversely, fish products are rich in polyunsaturated fatty acids and n-3 fatty acids, and are thought to protect against cerebral infarction via their hypolipidaemic, hypotensive, antiatherogenic, and antithrombotic effects.10 Unfortunately, such detailed information on the subtypes of cerebral infarction was unavailable in the present data. Other limitations in the present study include the unavailability of data to assess the reproducibility of the FFQ, although the FFQ has been validated. The FFQ included no information on portion size and nutrient intakes could not be estimated.51 However, possible misclassifications between haemorrhage and infarction strokes were unlikely because computerized tomography diagnosis was already in use when the study was initiated and thus the quality and reliability of death certificate information was likely to be sufficient.52 Although the study population is unique in the fact that most of the people had been exposed to ionizing radiation, there is no association between stroke risk and radiation exposure in the LSS cohort.21 Moreover, diet is not known to be associated with radiation exposure.51 Therefore, the present findings are also applicable to the general population. In conclusion, the large-scale population-based cohort study in Japan suggests that, in a country where animal product intake is generally low, a consumption of eggs, dairy products, and fish may reduce the risk of mortality from intracerebral haemorrhage. Table 1 Distribution of cerebrovascular deaths in men and women . Assigned ICD Codes . Men . Women . Total . Type of cerebrovascular disease . 9th Revision . 10th Revision . No . % . No . % . No . % . Subarachnoid haemorrhage 430 I60, I69.0 27 5.0 89 9.6 116 7.9 Intracerebral haemorrhage 431, 432 I61, I62, I69.1, I69.2 140 26.1 214 23.1 354 24.2 Cerebral infarction 433, 434 I63, I69.3 247 46.0 408 44.1 655 44.8 Other cerebrovascular diseases 435–438 I64–I68, I69.4, I69.8 123 22.9 214 23.1 337 23.1 Total 537 36.7 925 63.3 1462 100.0 . Assigned ICD Codes . Men . Women . Total . Type of cerebrovascular disease . 9th Revision . 10th Revision . No . % . No . % . No . % . Subarachnoid haemorrhage 430 I60, I69.0 27 5.0 89 9.6 116 7.9 Intracerebral haemorrhage 431, 432 I61, I62, I69.1, I69.2 140 26.1 214 23.1 354 24.2 Cerebral infarction 433, 434 I63, I69.3 247 46.0 408 44.1 655 44.8 Other cerebrovascular diseases 435–438 I64–I68, I69.4, I69.8 123 22.9 214 23.1 337 23.1 Total 537 36.7 925 63.3 1462 100.0 Open in new tab Table 1 Distribution of cerebrovascular deaths in men and women . Assigned ICD Codes . Men . Women . Total . Type of cerebrovascular disease . 9th Revision . 10th Revision . No . % . No . % . No . % . Subarachnoid haemorrhage 430 I60, I69.0 27 5.0 89 9.6 116 7.9 Intracerebral haemorrhage 431, 432 I61, I62, I69.1, I69.2 140 26.1 214 23.1 354 24.2 Cerebral infarction 433, 434 I63, I69.3 247 46.0 408 44.1 655 44.8 Other cerebrovascular diseases 435–438 I64–I68, I69.4, I69.8 123 22.9 214 23.1 337 23.1 Total 537 36.7 925 63.3 1462 100.0 . Assigned ICD Codes . Men . Women . Total . Type of cerebrovascular disease . 9th Revision . 10th Revision . No . % . No . % . No . % . Subarachnoid haemorrhage 430 I60, I69.0 27 5.0 89 9.6 116 7.9 Intracerebral haemorrhage 431, 432 I61, I62, I69.1, I69.2 140 26.1 214 23.1 354 24.2 Cerebral infarction 433, 434 I63, I69.3 247 46.0 408 44.1 655 44.8 Other cerebrovascular diseases 435–438 I64–I68, I69.4, I69.8 123 22.9 214 23.1 337 23.1 Total 537 36.7 925 63.3 1462 100.0 Open in new tab Table 2 Response frequencies for eight food frequency questions relating to animal products . Never . <Once/week . 2–4 times/week . Almost daily . Missing . Dietary factors . No. . % . No. . % . No. . % . No. . % . No. . % . Beef and pork 1160 3.1 8574 23.1 21 482 57.9 3237 8.7 2677 7.2 Chicken 2360 6.4 16 061 43.3 12 951 34.9 677 1.8 5081 13.7 Pork products 5287 14.2 14 749 39.7 8536 23.0 1284 3.5 7274 19.6 Milk 6021 16.2 8005 21.6 7435 20.0 10 371 27.9 5298 14.3 Eggs 716 1.9 6882 18.5 16 231 43.7 10 977 29.6 2324 6.3 Dairy products 7516 20.2 12 038 32.4 5418 14.6 3960 10.7 8198 22.1 Fish (except broiled) 561 1.5 9895 26.6 19 807 53.3 4398 11.8 2469 6.6 Broiled fish 1631 4.4 18 326 49.4 10 864 29.3 802 2.2 5507 14.8 . Never . <Once/week . 2–4 times/week . Almost daily . Missing . Dietary factors . No. . % . No. . % . No. . % . No. . % . No. . % . Beef and pork 1160 3.1 8574 23.1 21 482 57.9 3237 8.7 2677 7.2 Chicken 2360 6.4 16 061 43.3 12 951 34.9 677 1.8 5081 13.7 Pork products 5287 14.2 14 749 39.7 8536 23.0 1284 3.5 7274 19.6 Milk 6021 16.2 8005 21.6 7435 20.0 10 371 27.9 5298 14.3 Eggs 716 1.9 6882 18.5 16 231 43.7 10 977 29.6 2324 6.3 Dairy products 7516 20.2 12 038 32.4 5418 14.6 3960 10.7 8198 22.1 Fish (except broiled) 561 1.5 9895 26.6 19 807 53.3 4398 11.8 2469 6.6 Broiled fish 1631 4.4 18 326 49.4 10 864 29.3 802 2.2 5507 14.8 Open in new tab Table 2 Response frequencies for eight food frequency questions relating to animal products . Never . <Once/week . 2–4 times/week . Almost daily . Missing . Dietary factors . No. . % . No. . % . No. . % . No. . % . No. . % . Beef and pork 1160 3.1 8574 23.1 21 482 57.9 3237 8.7 2677 7.2 Chicken 2360 6.4 16 061 43.3 12 951 34.9 677 1.8 5081 13.7 Pork products 5287 14.2 14 749 39.7 8536 23.0 1284 3.5 7274 19.6 Milk 6021 16.2 8005 21.6 7435 20.0 10 371 27.9 5298 14.3 Eggs 716 1.9 6882 18.5 16 231 43.7 10 977 29.6 2324 6.3 Dairy products 7516 20.2 12 038 32.4 5418 14.6 3960 10.7 8198 22.1 Fish (except broiled) 561 1.5 9895 26.6 19 807 53.3 4398 11.8 2469 6.6 Broiled fish 1631 4.4 18 326 49.4 10 864 29.3 802 2.2 5507 14.8 . Never . <Once/week . 2–4 times/week . Almost daily . Missing . Dietary factors . No. . % . No. . % . No. . % . No. . % . No. . % . Beef and pork 1160 3.1 8574 23.1 21 482 57.9 3237 8.7 2677 7.2 Chicken 2360 6.4 16 061 43.3 12 951 34.9 677 1.8 5081 13.7 Pork products 5287 14.2 14 749 39.7 8536 23.0 1284 3.5 7274 19.6 Milk 6021 16.2 8005 21.6 7435 20.0 10 371 27.9 5298 14.3 Eggs 716 1.9 6882 18.5 16 231 43.7 10 977 29.6 2324 6.3 Dairy products 7516 20.2 12 038 32.4 5418 14.6 3960 10.7 8198 22.1 Fish (except broiled) 561 1.5 9895 26.6 19 807 53.3 4398 11.8 2469 6.6 Broiled fish 1631 4.4 18 326 49.4 10 864 29.3 802 2.2 5507 14.8 Open in new tab Table 3 Relative risk (HR) and 95% CI between non-dietary risk factors and stroke mortality . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Risk factors . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . aHR stratified by birth cohort and sex, and adjusted for city, radiation dose, and for each other. bBody mass index calculated from self-report data. Sex     Female 925 1.00 214 1.00 408 1.00     Male 537 1.07 0.92, 1.25 140 1.01 0.73, 1.39 247 1.21 0.97, 1.52 Smoking     Non-smoker 800 1.00 188 1.00 351 1.00     Current smoker 404 1.44 1.24, 1.68 118 1.44 1.06, 1.95 172 1.44 1.15, 1.81     Past smoker 198 1.12 0.93, 1.35 38 0.87 0.57, 1.32 99 1.20 0.91, 1.56 Alcohol     Non-drinker 717 1.00 170 1.00 317 1.00     Current drinker 560 0.99 0.87, 1.12 149 1.04 0.80, 1.35 255 1.01 0.83, 1.22     Past drinker 85 1.43 1.10, 1.86 20 1.78 1.05, 3.00 39 1.19 0.80, 1.76 Body mass indexb(kg/m2)     <19 294 1.00 73 1.00 126 1.00     19–<22 414 0.83 0.71, 0.97 120 0.91 0.67, 1.23 168 0.81 0.64, 1.02     22–<25 267 0.63 0.53, 0.75 68 0.53 0.37, 0.76 124 0.73 0.56, 0.94     25+ 201 0.90 0.74, 1.09 47 0.73 0.49, 1.07 94 1.06 0.80, 1.40 Education level     Low 850 1.00 186 1.00 394 1.00     Middle 369 0.89 0.78, 1.01 109 0.97 0.75, 1.26 156 0.92 0.76, 1.12     High 80 0.84 0.66, 1.08 25 0.95 0.61, 1.50 33 0.83 0.57, 1.21 History of diabetes     No 1293 1.00 311 1.00 571 1.00     Yes 169 1.19 1.01, 1.41 43 1.23 0.89, 1.72 84 1.28 1.00, 1.62 History of hypertension     No 794 1.00 179 1.00 352 1.00     Yes 668 1.64 1.47, 1.84 175 2.23 1.78, 2.79 303 1.55 1.32, 1.82 . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Risk factors . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . aHR stratified by birth cohort and sex, and adjusted for city, radiation dose, and for each other. bBody mass index calculated from self-report data. Sex     Female 925 1.00 214 1.00 408 1.00     Male 537 1.07 0.92, 1.25 140 1.01 0.73, 1.39 247 1.21 0.97, 1.52 Smoking     Non-smoker 800 1.00 188 1.00 351 1.00     Current smoker 404 1.44 1.24, 1.68 118 1.44 1.06, 1.95 172 1.44 1.15, 1.81     Past smoker 198 1.12 0.93, 1.35 38 0.87 0.57, 1.32 99 1.20 0.91, 1.56 Alcohol     Non-drinker 717 1.00 170 1.00 317 1.00     Current drinker 560 0.99 0.87, 1.12 149 1.04 0.80, 1.35 255 1.01 0.83, 1.22     Past drinker 85 1.43 1.10, 1.86 20 1.78 1.05, 3.00 39 1.19 0.80, 1.76 Body mass indexb(kg/m2)     <19 294 1.00 73 1.00 126 1.00     19–<22 414 0.83 0.71, 0.97 120 0.91 0.67, 1.23 168 0.81 0.64, 1.02     22–<25 267 0.63 0.53, 0.75 68 0.53 0.37, 0.76 124 0.73 0.56, 0.94     25+ 201 0.90 0.74, 1.09 47 0.73 0.49, 1.07 94 1.06 0.80, 1.40 Education level     Low 850 1.00 186 1.00 394 1.00     Middle 369 0.89 0.78, 1.01 109 0.97 0.75, 1.26 156 0.92 0.76, 1.12     High 80 0.84 0.66, 1.08 25 0.95 0.61, 1.50 33 0.83 0.57, 1.21 History of diabetes     No 1293 1.00 311 1.00 571 1.00     Yes 169 1.19 1.01, 1.41 43 1.23 0.89, 1.72 84 1.28 1.00, 1.62 History of hypertension     No 794 1.00 179 1.00 352 1.00     Yes 668 1.64 1.47, 1.84 175 2.23 1.78, 2.79 303 1.55 1.32, 1.82 Open in new tab Table 3 Relative risk (HR) and 95% CI between non-dietary risk factors and stroke mortality . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Risk factors . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . aHR stratified by birth cohort and sex, and adjusted for city, radiation dose, and for each other. bBody mass index calculated from self-report data. Sex     Female 925 1.00 214 1.00 408 1.00     Male 537 1.07 0.92, 1.25 140 1.01 0.73, 1.39 247 1.21 0.97, 1.52 Smoking     Non-smoker 800 1.00 188 1.00 351 1.00     Current smoker 404 1.44 1.24, 1.68 118 1.44 1.06, 1.95 172 1.44 1.15, 1.81     Past smoker 198 1.12 0.93, 1.35 38 0.87 0.57, 1.32 99 1.20 0.91, 1.56 Alcohol     Non-drinker 717 1.00 170 1.00 317 1.00     Current drinker 560 0.99 0.87, 1.12 149 1.04 0.80, 1.35 255 1.01 0.83, 1.22     Past drinker 85 1.43 1.10, 1.86 20 1.78 1.05, 3.00 39 1.19 0.80, 1.76 Body mass indexb(kg/m2)     <19 294 1.00 73 1.00 126 1.00     19–<22 414 0.83 0.71, 0.97 120 0.91 0.67, 1.23 168 0.81 0.64, 1.02     22–<25 267 0.63 0.53, 0.75 68 0.53 0.37, 0.76 124 0.73 0.56, 0.94     25+ 201 0.90 0.74, 1.09 47 0.73 0.49, 1.07 94 1.06 0.80, 1.40 Education level     Low 850 1.00 186 1.00 394 1.00     Middle 369 0.89 0.78, 1.01 109 0.97 0.75, 1.26 156 0.92 0.76, 1.12     High 80 0.84 0.66, 1.08 25 0.95 0.61, 1.50 33 0.83 0.57, 1.21 History of diabetes     No 1293 1.00 311 1.00 571 1.00     Yes 169 1.19 1.01, 1.41 43 1.23 0.89, 1.72 84 1.28 1.00, 1.62 History of hypertension     No 794 1.00 179 1.00 352 1.00     Yes 668 1.64 1.47, 1.84 175 2.23 1.78, 2.79 303 1.55 1.32, 1.82 . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Risk factors . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . No. cases . HRa . 95% CI . aHR stratified by birth cohort and sex, and adjusted for city, radiation dose, and for each other. bBody mass index calculated from self-report data. Sex     Female 925 1.00 214 1.00 408 1.00     Male 537 1.07 0.92, 1.25 140 1.01 0.73, 1.39 247 1.21 0.97, 1.52 Smoking     Non-smoker 800 1.00 188 1.00 351 1.00     Current smoker 404 1.44 1.24, 1.68 118 1.44 1.06, 1.95 172 1.44 1.15, 1.81     Past smoker 198 1.12 0.93, 1.35 38 0.87 0.57, 1.32 99 1.20 0.91, 1.56 Alcohol     Non-drinker 717 1.00 170 1.00 317 1.00     Current drinker 560 0.99 0.87, 1.12 149 1.04 0.80, 1.35 255 1.01 0.83, 1.22     Past drinker 85 1.43 1.10, 1.86 20 1.78 1.05, 3.00 39 1.19 0.80, 1.76 Body mass indexb(kg/m2)     <19 294 1.00 73 1.00 126 1.00     19–<22 414 0.83 0.71, 0.97 120 0.91 0.67, 1.23 168 0.81 0.64, 1.02     22–<25 267 0.63 0.53, 0.75 68 0.53 0.37, 0.76 124 0.73 0.56, 0.94     25+ 201 0.90 0.74, 1.09 47 0.73 0.49, 1.07 94 1.06 0.80, 1.40 Education level     Low 850 1.00 186 1.00 394 1.00     Middle 369 0.89 0.78, 1.01 109 0.97 0.75, 1.26 156 0.92 0.76, 1.12     High 80 0.84 0.66, 1.08 25 0.95 0.61, 1.50 33 0.83 0.57, 1.21 History of diabetes     No 1293 1.00 311 1.00 571 1.00     Yes 169 1.19 1.01, 1.41 43 1.23 0.89, 1.72 84 1.28 1.00, 1.62 History of hypertension     No 794 1.00 179 1.00 352 1.00     Yes 668 1.64 1.47, 1.84 175 2.23 1.78, 2.79 303 1.55 1.32, 1.82 Open in new tab Table 4 Relative risk (HR) and 95% CI between each animal product intake and total stroke mortality . . Total stroke . . Dietary factor . No. subjects . No. cases . HR (95%CI) . P-trend . HR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, history of diabetes, or hypertension. HR for missing category not shown. Beef and pork     Never 1160 93 1.00 (reference)     ≤1 time/week 8574 420 0.83 (0.65, 1.06)     2–4 times/week 21 482 630 0.80 (0.63, 1.02)     Almost daily 3237 81 1.01 (0.73, 1.38) 0.857 Chicken     Never 2360 102 1.00 (reference)     ≤1 time/week 16 061 511 0.88 (0.70, 1.10)     2–4 times/week 12 951 479 0.99 (0.79, 1.25)     Almost daily 677 40 1.43 (0.98, 2.10) 0.011 Pork products     Never 5287 284 1.00 (reference)     ≤1 time/week 14 749 425 0.96 (0.82, 1.12)     2–4 times/week 8536 219 1.03 (0.85, 1.24)     Almost daily 1284 30 0.90 (0.61, 1.33) 0.812 Milk     Never 6021 258 1.00 (reference)     ≤1 time/week 8005 289 1.06 (0.89, 1.26)     2–4 times/week 7435 204 1.02 (0.84, 1.23)     Almost daily 10 371 343 0.94 (0.79, 1.12) 0.232 Eggs     Never 716 52 1.00 (reference)     ≤1 time/week 6882 315 0.75 (0.55, 1.01)     2–4 times/week 16 231 563 0.77 (0.57, 1.03)     Almost daily 10 977 329 0.70 (0.51, 0.95) 0.185 Dairy products     Never 7516 371 1.00 (reference)     ≤1 time/week 12 038 321 0.99 (0.84, 1.16)     2–4 times/week 5418 132 1.00 (0.81, 1.23)     Almost daily 3690 85 0.73 (0.57–0.94) 0.024 Fish (except broiled)     Never 561 31 1.00 (reference)     ≤1 time/week 9895 395 0.82 (0.57, 1.19)     2–4 times/week 19 807 657 0.74 (0.51, 1.06)     Almost daily 4398 177 0.71 (0.48, 1.05) 0.046 Broiled fish     Never 1631 82 1.00 (reference)     ≤1 time/week 18 326 577 0.82 (0.64, 1.04)     2–4 times/week 10864 386 0.83 (0.65, 1.06)     Almost daily 802 23 0.60 (0.37, 0.98) 0.428 . . Total stroke . . Dietary factor . No. subjects . No. cases . HR (95%CI) . P-trend . HR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, history of diabetes, or hypertension. HR for missing category not shown. Beef and pork     Never 1160 93 1.00 (reference)     ≤1 time/week 8574 420 0.83 (0.65, 1.06)     2–4 times/week 21 482 630 0.80 (0.63, 1.02)     Almost daily 3237 81 1.01 (0.73, 1.38) 0.857 Chicken     Never 2360 102 1.00 (reference)     ≤1 time/week 16 061 511 0.88 (0.70, 1.10)     2–4 times/week 12 951 479 0.99 (0.79, 1.25)     Almost daily 677 40 1.43 (0.98, 2.10) 0.011 Pork products     Never 5287 284 1.00 (reference)     ≤1 time/week 14 749 425 0.96 (0.82, 1.12)     2–4 times/week 8536 219 1.03 (0.85, 1.24)     Almost daily 1284 30 0.90 (0.61, 1.33) 0.812 Milk     Never 6021 258 1.00 (reference)     ≤1 time/week 8005 289 1.06 (0.89, 1.26)     2–4 times/week 7435 204 1.02 (0.84, 1.23)     Almost daily 10 371 343 0.94 (0.79, 1.12) 0.232 Eggs     Never 716 52 1.00 (reference)     ≤1 time/week 6882 315 0.75 (0.55, 1.01)     2–4 times/week 16 231 563 0.77 (0.57, 1.03)     Almost daily 10 977 329 0.70 (0.51, 0.95) 0.185 Dairy products     Never 7516 371 1.00 (reference)     ≤1 time/week 12 038 321 0.99 (0.84, 1.16)     2–4 times/week 5418 132 1.00 (0.81, 1.23)     Almost daily 3690 85 0.73 (0.57–0.94) 0.024 Fish (except broiled)     Never 561 31 1.00 (reference)     ≤1 time/week 9895 395 0.82 (0.57, 1.19)     2–4 times/week 19 807 657 0.74 (0.51, 1.06)     Almost daily 4398 177 0.71 (0.48, 1.05) 0.046 Broiled fish     Never 1631 82 1.00 (reference)     ≤1 time/week 18 326 577 0.82 (0.64, 1.04)     2–4 times/week 10864 386 0.83 (0.65, 1.06)     Almost daily 802 23 0.60 (0.37, 0.98) 0.428 Open in new tab Table 4 Relative risk (HR) and 95% CI between each animal product intake and total stroke mortality . . Total stroke . . Dietary factor . No. subjects . No. cases . HR (95%CI) . P-trend . HR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, history of diabetes, or hypertension. HR for missing category not shown. Beef and pork     Never 1160 93 1.00 (reference)     ≤1 time/week 8574 420 0.83 (0.65, 1.06)     2–4 times/week 21 482 630 0.80 (0.63, 1.02)     Almost daily 3237 81 1.01 (0.73, 1.38) 0.857 Chicken     Never 2360 102 1.00 (reference)     ≤1 time/week 16 061 511 0.88 (0.70, 1.10)     2–4 times/week 12 951 479 0.99 (0.79, 1.25)     Almost daily 677 40 1.43 (0.98, 2.10) 0.011 Pork products     Never 5287 284 1.00 (reference)     ≤1 time/week 14 749 425 0.96 (0.82, 1.12)     2–4 times/week 8536 219 1.03 (0.85, 1.24)     Almost daily 1284 30 0.90 (0.61, 1.33) 0.812 Milk     Never 6021 258 1.00 (reference)     ≤1 time/week 8005 289 1.06 (0.89, 1.26)     2–4 times/week 7435 204 1.02 (0.84, 1.23)     Almost daily 10 371 343 0.94 (0.79, 1.12) 0.232 Eggs     Never 716 52 1.00 (reference)     ≤1 time/week 6882 315 0.75 (0.55, 1.01)     2–4 times/week 16 231 563 0.77 (0.57, 1.03)     Almost daily 10 977 329 0.70 (0.51, 0.95) 0.185 Dairy products     Never 7516 371 1.00 (reference)     ≤1 time/week 12 038 321 0.99 (0.84, 1.16)     2–4 times/week 5418 132 1.00 (0.81, 1.23)     Almost daily 3690 85 0.73 (0.57–0.94) 0.024 Fish (except broiled)     Never 561 31 1.00 (reference)     ≤1 time/week 9895 395 0.82 (0.57, 1.19)     2–4 times/week 19 807 657 0.74 (0.51, 1.06)     Almost daily 4398 177 0.71 (0.48, 1.05) 0.046 Broiled fish     Never 1631 82 1.00 (reference)     ≤1 time/week 18 326 577 0.82 (0.64, 1.04)     2–4 times/week 10864 386 0.83 (0.65, 1.06)     Almost daily 802 23 0.60 (0.37, 0.98) 0.428 . . Total stroke . . Dietary factor . No. subjects . No. cases . HR (95%CI) . P-trend . HR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, history of diabetes, or hypertension. HR for missing category not shown. Beef and pork     Never 1160 93 1.00 (reference)     ≤1 time/week 8574 420 0.83 (0.65, 1.06)     2–4 times/week 21 482 630 0.80 (0.63, 1.02)     Almost daily 3237 81 1.01 (0.73, 1.38) 0.857 Chicken     Never 2360 102 1.00 (reference)     ≤1 time/week 16 061 511 0.88 (0.70, 1.10)     2–4 times/week 12 951 479 0.99 (0.79, 1.25)     Almost daily 677 40 1.43 (0.98, 2.10) 0.011 Pork products     Never 5287 284 1.00 (reference)     ≤1 time/week 14 749 425 0.96 (0.82, 1.12)     2–4 times/week 8536 219 1.03 (0.85, 1.24)     Almost daily 1284 30 0.90 (0.61, 1.33) 0.812 Milk     Never 6021 258 1.00 (reference)     ≤1 time/week 8005 289 1.06 (0.89, 1.26)     2–4 times/week 7435 204 1.02 (0.84, 1.23)     Almost daily 10 371 343 0.94 (0.79, 1.12) 0.232 Eggs     Never 716 52 1.00 (reference)     ≤1 time/week 6882 315 0.75 (0.55, 1.01)     2–4 times/week 16 231 563 0.77 (0.57, 1.03)     Almost daily 10 977 329 0.70 (0.51, 0.95) 0.185 Dairy products     Never 7516 371 1.00 (reference)     ≤1 time/week 12 038 321 0.99 (0.84, 1.16)     2–4 times/week 5418 132 1.00 (0.81, 1.23)     Almost daily 3690 85 0.73 (0.57–0.94) 0.024 Fish (except broiled)     Never 561 31 1.00 (reference)     ≤1 time/week 9895 395 0.82 (0.57, 1.19)     2–4 times/week 19 807 657 0.74 (0.51, 1.06)     Almost daily 4398 177 0.71 (0.48, 1.05) 0.046 Broiled fish     Never 1631 82 1.00 (reference)     ≤1 time/week 18 326 577 0.82 (0.64, 1.04)     2–4 times/week 10864 386 0.83 (0.65, 1.06)     Almost daily 802 23 0.60 (0.37, 0.98) 0.428 Open in new tab Table 5 Relative risk (HR) and 95% CI between intake of animal products and stroke mortality . . . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Dietary factor . Median intake (range) in g/day . No. subjects . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . aHR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, self-reported history of diabetes, or hypertension. bBeef and pork, chicken, pork products, milk, egg, dairy products, fish, broiled fish. cEgg, dairy products, fish, broiled fish. dFish, broiled fish. eBased on one estimate. All animal productsb     Low 121 (91–141) 12 311 683 1.00 (reference) 173 1.00 (reference) 303 1.00 (reference)     Moderate 180 (148–251) 10 956 405 0.92 (0.81, 1.05) 86 0.71 (0.54, 0.93) 191 1.00 (0.83, 1.21)     High 231 (209–326) 13 863 374 0.88 (0.77, 1.00) 95 0.76 (0.58, 0.99) 161 0.89 (0.73, 1.09)     P-trend 0.0445 0.0266 0.3004 Significant animal productsc     Low 31 (30–40) 10 019 546 1.00 (reference) 138 1.00 (reference) 240 1.00 (reference)     Moderate 62 (58–73) 17 569 656 0.87 (0.77, 0.98) 148 0.67 (0.53, 0.86) 299 0.95 (0.79, 1.13)     High 102 (94–105) 9542 260 0.80 (0.68, 0.93) 68 0.72 (0.53, 0.98) 116 0.84 (0.67, 1.06)     P-trend 0.0048 0.0061 0.2330 Fish productsd     Low 18 (11–18) 11 178 552 1.00 (reference) 142 1.00 (reference) 239 1.00 (reference)     Moderate 30 (30–30)e 13 794 471 0.85 (0.75, 0.97) 110 0.70 (0.54, 0.91) 209 0.90 (0.74, 1.09)     High 46 (46–65) 12 158 439 0.85 (0.75, 0.98) 102 0.70 (0.54, 0.92) 207 0.94 (0.77, 1.14)     P-trend 0.0169 0.0078 0.4999 . . . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Dietary factor . Median intake (range) in g/day . No. subjects . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . aHR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, self-reported history of diabetes, or hypertension. bBeef and pork, chicken, pork products, milk, egg, dairy products, fish, broiled fish. cEgg, dairy products, fish, broiled fish. dFish, broiled fish. eBased on one estimate. All animal productsb     Low 121 (91–141) 12 311 683 1.00 (reference) 173 1.00 (reference) 303 1.00 (reference)     Moderate 180 (148–251) 10 956 405 0.92 (0.81, 1.05) 86 0.71 (0.54, 0.93) 191 1.00 (0.83, 1.21)     High 231 (209–326) 13 863 374 0.88 (0.77, 1.00) 95 0.76 (0.58, 0.99) 161 0.89 (0.73, 1.09)     P-trend 0.0445 0.0266 0.3004 Significant animal productsc     Low 31 (30–40) 10 019 546 1.00 (reference) 138 1.00 (reference) 240 1.00 (reference)     Moderate 62 (58–73) 17 569 656 0.87 (0.77, 0.98) 148 0.67 (0.53, 0.86) 299 0.95 (0.79, 1.13)     High 102 (94–105) 9542 260 0.80 (0.68, 0.93) 68 0.72 (0.53, 0.98) 116 0.84 (0.67, 1.06)     P-trend 0.0048 0.0061 0.2330 Fish productsd     Low 18 (11–18) 11 178 552 1.00 (reference) 142 1.00 (reference) 239 1.00 (reference)     Moderate 30 (30–30)e 13 794 471 0.85 (0.75, 0.97) 110 0.70 (0.54, 0.91) 209 0.90 (0.74, 1.09)     High 46 (46–65) 12 158 439 0.85 (0.75, 0.98) 102 0.70 (0.54, 0.92) 207 0.94 (0.77, 1.14)     P-trend 0.0169 0.0078 0.4999 Open in new tab Table 5 Relative risk (HR) and 95% CI between intake of animal products and stroke mortality . . . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Dietary factor . Median intake (range) in g/day . No. subjects . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . aHR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, self-reported history of diabetes, or hypertension. bBeef and pork, chicken, pork products, milk, egg, dairy products, fish, broiled fish. cEgg, dairy products, fish, broiled fish. dFish, broiled fish. eBased on one estimate. All animal productsb     Low 121 (91–141) 12 311 683 1.00 (reference) 173 1.00 (reference) 303 1.00 (reference)     Moderate 180 (148–251) 10 956 405 0.92 (0.81, 1.05) 86 0.71 (0.54, 0.93) 191 1.00 (0.83, 1.21)     High 231 (209–326) 13 863 374 0.88 (0.77, 1.00) 95 0.76 (0.58, 0.99) 161 0.89 (0.73, 1.09)     P-trend 0.0445 0.0266 0.3004 Significant animal productsc     Low 31 (30–40) 10 019 546 1.00 (reference) 138 1.00 (reference) 240 1.00 (reference)     Moderate 62 (58–73) 17 569 656 0.87 (0.77, 0.98) 148 0.67 (0.53, 0.86) 299 0.95 (0.79, 1.13)     High 102 (94–105) 9542 260 0.80 (0.68, 0.93) 68 0.72 (0.53, 0.98) 116 0.84 (0.67, 1.06)     P-trend 0.0048 0.0061 0.2330 Fish productsd     Low 18 (11–18) 11 178 552 1.00 (reference) 142 1.00 (reference) 239 1.00 (reference)     Moderate 30 (30–30)e 13 794 471 0.85 (0.75, 0.97) 110 0.70 (0.54, 0.91) 209 0.90 (0.74, 1.09)     High 46 (46–65) 12 158 439 0.85 (0.75, 0.98) 102 0.70 (0.54, 0.92) 207 0.94 (0.77, 1.14)     P-trend 0.0169 0.0078 0.4999 . . . Total stroke . Intracerebral haemorrhage . Cerebral infarction . Dietary factor . Median intake (range) in g/day . No. subjects . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . No. cases . HR (95% CI)a . aHR stratified by sex and birth cohort, and adjusted for city, radiation dose, self-reported body mass index, smoking status, alcohol habits, education level, self-reported history of diabetes, or hypertension. bBeef and pork, chicken, pork products, milk, egg, dairy products, fish, broiled fish. cEgg, dairy products, fish, broiled fish. dFish, broiled fish. eBased on one estimate. All animal productsb     Low 121 (91–141) 12 311 683 1.00 (reference) 173 1.00 (reference) 303 1.00 (reference)     Moderate 180 (148–251) 10 956 405 0.92 (0.81, 1.05) 86 0.71 (0.54, 0.93) 191 1.00 (0.83, 1.21)     High 231 (209–326) 13 863 374 0.88 (0.77, 1.00) 95 0.76 (0.58, 0.99) 161 0.89 (0.73, 1.09)     P-trend 0.0445 0.0266 0.3004 Significant animal productsc     Low 31 (30–40) 10 019 546 1.00 (reference) 138 1.00 (reference) 240 1.00 (reference)     Moderate 62 (58–73) 17 569 656 0.87 (0.77, 0.98) 148 0.67 (0.53, 0.86) 299 0.95 (0.79, 1.13)     High 102 (94–105) 9542 260 0.80 (0.68, 0.93) 68 0.72 (0.53, 0.98) 116 0.84 (0.67, 1.06)     P-trend 0.0048 0.0061 0.2330 Fish productsd     Low 18 (11–18) 11 178 552 1.00 (reference) 142 1.00 (reference) 239 1.00 (reference)     Moderate 30 (30–30)e 13 794 471 0.85 (0.75, 0.97) 110 0.70 (0.54, 0.91) 209 0.90 (0.74, 1.09)     High 46 (46–65) 12 158 439 0.85 (0.75, 0.98) 102 0.70 (0.54, 0.92) 207 0.94 (0.77, 1.14)     P-trend 0.0169 0.0078 0.4999 Open in new tab Figure 1 Open in new tabDownload slide Temporal trends in intakes of animal products in Japan between 1959 and 1998, estimated from the National Nutrition surveys, based on a 24-hour diary Figure 1 Open in new tabDownload slide Temporal trends in intakes of animal products in Japan between 1959 and 1998, estimated from the National Nutrition surveys, based on a 24-hour diary Open in new tabDownload slide Traditional Japanese sushi. 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TI - Intake of animal products and stroke mortality in the Hiroshima/Nagasaki Life Span Study
JF - International Journal of Epidemiology
DO - 10.1093/ije/dyg151
DA - 2003-08-01
UR - https://www.deepdyve.com/lp/oxford-university-press/intake-of-animal-products-and-stroke-mortality-in-the-hiroshima-c0Y16bE7AF
SP - 536
EP - 543
VL - 32
IS - 4
DP - DeepDyve
ER -