American Journal of Epidemiology

Ramlow, Jonathan; Alexander, Michael; LaPorte, Ronald; Kaufmann, Caroline; Kuller, Lewis

doi: 10.1093/aje/136.7.769pmid: 1442743

A late-onset syndrome, consisting of muscle weakness, muscle pain, and unaccustomed fatigue, has been reported with increasing frequency among former poliomyelitis patients. A population-based cohort of poliomyelitis patients from Allegheny County, Pennsylvania, was traced and surveyed to estimate the prevalence and incidence and to identify determinants of the post-polio syndrome. A questionnaire validated in clinical examinations of 40 cohort members was used in the survey. The prevalence of the post-polio syndrome was 28.5% of all paralytic cases (95% confidence interval 24.4–32.6). The risk of post-polio syndrome was significantly higher among patients who sustained substantial permanent impairment after polio and among females. The incidence did not vary with age at acute onset, acute severity, or level of physical activity after recovery. The strongest determinant of post-polio syndrome onset was the length of the interval following the acute illness, with incidence peaking at 30–34 years. Of all cases of post-polio syndrome, 79% reported no major change in impairment status since onset. This study demonstrates that poliomyelitis patients are not equally susceptible to post-polio syndrome within the interval of 30–40 years after the original illness. For syndrome cases, the onset was associated with new neuromuscular symptoms and functional changes but not with major new impairment.

Kono, Suminori; Shinichi, Koichi; Ikeda, Nariaki; Yanai, Fumio; Imanishi, Koji

doi: 10.1093/aje/136.7.787pmid: 1442744

Risk factors of gallstone disease were investigated in male self-defense officials who received, between October 1986 and December 1990, a retirement health examination at the Self-Defense Forces Fukuoka Hospital, Fukuoka, Japan. Gallbladder ultrasonography, successfully performed with 2,739 of 2,756 men, found 61 men with gallstones and 38 men with previous removal of the gallbladder; the overall prevalence of gallstone disease was 3.6%. Multiple logistic regression analysis assessed the risk of gallstone disease in relation to smoking, alcohol use, body mass index, glucose tolerance, and rank. Alcohol use was associated with a decreased risk, and body mass index was positively related to gallstone disease. Men with impaired glucose tolerance had a slightly elevated risk, whereas diabetes mellitus was not associated with gallstone disease. Analysis for prevalent gallstones and the postcholecystectomy state showed an inverse association of alcohol use with the latter; a positive association with impaired glucose tolerance was also confined primarily to the latter condition. These findings provide little support for a protective effect of alcohol use in the formation of gallstones. It was inconclusive whether impaired glucose tolerance was associated selectively with postcholecystectomy.

Stein, Aryeh D.; Shea, Steven; Basch, Charles E.; Zybert, Patricia

doi: 10.1093/aje/136.7.795pmid: 1442745

Few studies have examined the relation of blood pressure reactivity to subsequent change in blood pressure of preschool children. The authors investigated relations between measurement-induced reactivity, exercise reactivity, and change in blood pressure over 16 months among 140 preschool children (46–67 months of age at baseline, 50.7% female, 92.9% Hispanic). Within-session measurement-induced reactivity was defined as the change in blood pressure between the first and the mean of the fourth and fifth readings obtained at each of 11 sessions. Between-session measurement-induced reactivity was defined as the change between mean blood pressure at session 1 and the mean of sessions 2 and 3. Both indices of measurement reactivity displayed poor reproducibility. Exercise reactivity was measured using a treadmill on two occasions and was moderately reproducible. There was no association between measurement and exercise reactivity. The change in systolic blood pressure over time was not associated with any measure of reactivity. The mean diastolic blood pressure did not change over the study period. Neither blood pressure reactivity to measurement nor blood pressure reactivity to exercise appeared to be a useful predictor of change in blood pressure in preschool children during a 16-month period.

Lakka, T. A.; Salonen, J. T.

doi: 10.1093/aje/136.7.806pmid: 1442746

The authors studied the association of the type, amount, and intensity of physical activity with serum lipids in 2,492 randomly selected eastern Finnish men aged 42–60 years during 1984–1989, controlling for the major confounding factors. High density lipoprotein cholesterol (HDL cholesterol) and HDL2 cholesterol were associated positively and triglycerides inversely with total, occupational, and leisure time activity in a multivariate regression model (p < 0.001). HDL3 cholesterol was associated positively only with total activity (p <0.001). The adjusted relative differences in HDL cholesterol, HDL2 cholesterol, HDL3 cholesterol, and triglycerides between extreme total (occupational, leisure time) activity quartiles were 10.7% (9.0%, 5.7%), 12.2% (10.3%, 9.5%), 5.9% (2.9%, 0%), and 22.7% (9.2%, 10.4%), respectively. HDL cholesterol and HDL2 cholesterol were the highest and triglycerides the lowest at a conditioning activity intensity of more than 6 metabolic units (p < 0.001). The strongest associations were found for the 24-Hour Recording, which suggests short-term effects of physical activity on serum lipids. The beneficial effects of physical activity on serum lipids appear to be mediated partially by a reduced serum insulin concentration and decreased body adiposity. These data provide further confirmation for the concept that both regular or at least moderate intensity leisure time activity and occupational physical activity have a favorable impact on serum lipids.

Jackson, Rodney; Scragg, Robert; Beaglehole, Robert

doi: 10.1093/aje/136.7.819pmid: 1442747

This study, conducted in Auckland, New Zealand, over 2 years from March 1986, used a case-control design to investigate the hypothesis that alcohol acutely increases the risk of both nonfatal myocardial infarction and coronary death in the 24 hours after drinking, among regular drinkers. The nonfatal myocardial infarction analyses included 278 male and 60 female cases identified from a population-based coronary heart disease surveillance program and 458 male and 266 female controls randomly selected from the same population matched by age and sex. In the coronary death analyses, 172 male and 16 female coronary death cases from the same surveillance program and a population-based sample of 294 males and 165 females who were age and sex matched were examined. Information on alcohol consumption in the 24 hours before the coronary event in cases and a comparable 24-hour period in controls was collected. Study subjects all drank alcohol regularly at least once per month and were aged 25–64 years. Controls were more likely than cases to report a drinking episode in the 24-hour period examined in both sexes and for fatal and nonfatal disease. After controlling for possible confounding, the authors found that drinkers had a consistently lower estimated risk of both fatal and nonfatal coronary heart disease than participants reporting no alcohol in the previous 24 hours. The odds ratios ranged from 0.75 (95% confidence interval 0.62–0.90) for nonfatal myocardial infarction in men to 0.46 (95% confidence interval 0.19–1.10) for coronary death in women. There were no clear differences in estimated acute risk among those who drank one or two drinks, three or four drinks, or more than four drinks in the 24-hour period. These findings suggest that, contrary to previous speculation, alcohol consumption may acutely reduce coronary heart disease risk.

Wilkens, Lynne R.; Hankin, Jean H.; Yoshizawa, Carl N.; Kolonel, Laurence N.; Lee, James

doi: 10.1093/aje/136.7.825pmid: 1442748

A quantitative history of current dietary intake based on 83 food items was administered by interview to a representative sample of 4,809 subjects in Hawaii in 1977–1979. In 1983–1987, this history was readministered to the 131 original respondents who had subsequently developed cancer, as well as 413 randomly selected subjects who remained cancer free. A surrogate was interviewed when the original subject was unavailable. The repeat interview elicited information about diet at the time of the original interview. The authors found that recall values for macronutrients were consistently higher than original levels for both cases and noncases, which may be due in part to a modification in the administration of the repeat questionnaire. Although there were no marked differences overall between cases and noncases in the ability to recall past diet, differences between the two groups were seen in certain subsets of the sample. In the subgroup with the longest recall interval (8–10 years), cases were not able to recall their diets as well as noncases. Also, the difference between original and recall values was larger for cases with colorectal cancer and all cases diagnosed with distant stage disease, compared with noncases. This was not true for cases of breast and prostate cancer and those with localized or regional disease. The following variables were found to have no significant effect on recall for cases or noncases: sex, age, education, and type of respondent (surrogate or subject). Of the five major ethnic groups included in the study, Japanese had the best recall of their past diets, while respondents reporting a diet change between the interviews had poorer recall than did those who reported no change. These results suggest that differential misclassification in dietary case-control studies may pose a significant problem in certain instances, but that these studies can yield meaningful results with certain constraints on the study population. Am J Epidemiol 1992;136:825–35.

IJsselmuiden, Carel B.; Gaydos, Charlotte; Feighner, Brian; Novakoski, William L.; Serwadda, David; Caris, Luis H.; Vlahov, David; Comstock, George W.

doi: 10.1093/aje/136.7.836pmid: 1442749

A case-control study was done to assess a potential association between drinking water and pancreatic cancer in Washington County, Maryland. Cases of pancreatic cancer occurring from 1975 through 1989 were identified from the cancer registry. Controls were selected from the private 1975 census of Washington County. There were 101 cases and 206 controls. Chlorinated municipal water was used as a source of drinking water by 79% of cases and 63% of controls, yielding a significant odds ratio of 2.2. Adjustment for age and smoking had almost no effect on the risk, although both age and smoking were independently associated with an increased risk of pancreatic cancer. Although these findings must be interpreted with caution because of limitations in exposure assessment, these results have implications for the prevention of pancreatic cancer because chlorination of water is so widely practiced.

Santos-Burgoa, Carlos; Matanoski, Genevieve M.; Zeger, Scott; Schwartz, Linda

doi: 10.1093/aje/136.7.843pmid: 1442750

1,3-Butadiene and styrene are suspected carcinogens and common chemicals used in the synthesis of rubber. To investigate any potential human hazards from exposure to these chemicals, a case-control study of 59 lymphohematopoietic cancers was conducted within a cohort of male workers employed between 1943 and 1982 in eight North American styrene-butadiene rubber polymer-producing plants. A total of 193 controls were matched to the cases by plant, age, year of hire, duration worked, and survival to time of death of the case. Each job was assigned an estimated exposure rank, and each worker's cumulated rank score was calculated on the basis of the time spent in each job throughout his employment. “Exposure” as a dichotomous variable was defined as a log rank score above the mean of the log scores for the total population of cases and controls within a subtype of cancer. Matched-pair analysis identified a strong association between leukemia and butadiene, with an odds ratio of 9.36 (95% confidence interval 2.05–22.9) and an association between styrene and leukemia (odds ratio = 3.13, 95% confidence interval 0.84–11.2) that did not achieve statistical significance. When exposure to both styrene and butadiene was included in a conditional logistic regression model, the odds ratio for butadiene remained high (odds ratio = 7.39), but the estimated association of leukemia with styrene was small. The results of this study support the hypothesis that exposure to butadiene is associated with the risk of leukemia. There also appears to be an additional risk from work in specific subdivisions of the industry.

Steenland, Kule; Nowlin, Sue; Adams, Steven

doi: 10.1093/aje/136.7.855pmid: 1442751

The authors have created US mortality rates (age, sex, race, and calendar-time specific) and proportions, using multiple cause-of-death data, for the years 1960–1989. Multiple cause-of-death data include the usual underlying cause of death from the death certificate as well as contributory causes and other significant conditions. US multiple-cause rates and proportions enable the user to calculate the expected occurrences of disease on the death certificates of a cohort under study. There is an average of 2.66 causes and/or contributory conditions listed on US death certificates, increasing over time from 2.54 in the 1960s to 2.76 in the 1980s. The ratio of multiple-cause listings to underlying cause listings varies by disease, from low ratios for cancers to high ratios for diseases such as diabetes, arthritis, prostate disease, hypertension, pneumoconiosis, and renal disease. Use of these data is illustrated with two cohorts. Multiple-cause analysis (but not underlying cause analysis) revealed twofold significant excesses of renal disease and arthritis among granite cutters. For workers exposed to dioxin, neither multiple-cause nor underlying cause analysis indicated any excess of diabetes, an outcome of a priori interest. Good candidates for multiple-cause analysis are diseases that are of long duration, not necessarily fatal, yet serious enough to be listed on the death certificate.

Romano, Patrick S.; McLoughlin, Elizabeth

doi: 10.1093/aje/136.7.863pmid: 1442752

Protective gear (for example, helmets and bulletproof vests) shields certain body regions from damaging energy. Failure to specify on death certificates the body region and nature of fatal injuries compromises the utility of mortality data for epidemiologic or prevention research. Of fatally injured California motorcyclists, 41% had no specific injuries listed on their death certificates in 1988. To examine the implications of this problem, the authors abstracted 186 coroner's or medical examiner's reports from four California counties with over 60% nonspecific injuries and one county with few such injuries. These data were merged with computerized death certificate files and with the Fatal Accident Reporting System. Among the 99 cases with nonspecific injury codes, 68% had head injuries, 63% had chest injuries, 58% had abdominal injuries, and 58% had extremity injuries. Reporting sensitivity in the four problem counties varied from 36% for head injury to less than 5% for abdominal, spinal, and extremity injury. The association between head injury and failure to wear a helmet was statistically significant using the coroner's diagnoses (p = 0.02), but not using death certificate diagnoses (p = 0.17). The value of mortality data to injury researchers would be enhanced by better reporting of the nature of injury on death certificates.