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J E Manson

Publications and source records attributed to J E Manson.

At least 109 records · Page 6Linked to original sources
PubMed1999

Prospective study of adult onset diabetes mellitus (type 2) and risk of colorectal cancer in women.

BACKGROUND: The remarkable similarity of lifestyle and environmental risk factors for type 2 (non-insulin-dependent) diabetes mellitus and colon cancer has led to the hypothesis that diabetes may increase the risk of this cancer. We prospectively examined the relationship between diabetes and risk of colorectal cancer in a cohort of 118403 women aged 30 through 55 years who were without previously diagnosed cancer at baseline in 1976. METHODS: The women, who were enrolled in the Nurses' Health Study, were assessed for history of diabetes at baseline and during follow-up by use of biennial questionnaires. Self-reported diabetes was validated by information obtained from a supplemental questionnaire on symptoms and treatment and was confirmed by medical record review in a sample of the participants. Incident cases of colorectal cancer were ascertained through medical record review. All reported P values are two-sided. RESULTS: During 18 years of follow-up (201061 person-years), we documented 892 new cases of colorectal cancer. After adjustment for age, body mass index (weight in kg/height in m2), physical activity, and other covariates, relative risks (RRs) were 1.43 (95% confidence interval [CI] = 1.10-1.87; P = .009) for colorectal cancer, 1.49 (95% CI = 1.09-2.06; P = .01) for colon cancer, 1.11 (95% CI = 0.56-2.21; P = .76) for rectal cancer, 1.56 (95% CI = 1.07-2.28; P = .02) for advanced colorectal cancer, and 2.39 (95% CI = 1.46-3.92; P = .0005) for fatal colorectal cancer. CONCLUSION: Our data provide support for the hypothesis that diabetes is associated with an increased risk of colorectal cancer in women.

Adult↗
PubMed1999

Dietary carotenoids and vitamins A, C, and E and risk of breast cancer.

BACKGROUND: Data on intake of specific carotenoids and breast cancer risk are limited. Furthermore, studies of vitamins A, C, and E in relation to breast cancer risk are inconclusive. We have conducted a large, prospective study to evaluate long-term intakes of these nutrients and breast cancer risk. METHODS: We examined, by use of multivariate analysis, associations between intakes of specific carotenoids, vitamins A, C, and E , consumption of fruits and vegetables, and breast cancer risk in a cohort of 83234 women (aged 33-60 years in 1980) who were participating in the Nurses' Health Study. Through 1994, we identified 2697 incident cases of invasive breast cancer (784 premenopausal and 1913 postmenopausal). RESULTS: Intakes of beta-carotene from food and supplements, lutein/zeaxanthin, and vitamin A from foods were weakly inversely associated with breast cancer risk in premenopausal women. Strong inverse associations were found for increasing quintiles of alpha-carotene, beta-carotene, lutein/zeaxanthin, total vitamin C from foods, and total vitamin A among premenopausal women with a positive family history of breast cancer. An inverse association was also found for increasing quintiles of beta-carotene among premenopausal women who consumed 15 g or more of alcohol per day. Premenopausal women who consumed five or more servings per day of fruits and vegetables had modestly lower risk of breast cancer than those who had less than two servings per day (relative risk [RR] = 0.77; 95% confidence interval [CI] = 0.58-1.02); this association was stronger among premenopausal women who had a positive family history of breast cancer (RR = 0.29; 95% CI = 0.13-0.62) or those who consumed 15 g or more of alcohol per day (RR = 0.53; 95% CI = 0.27-1.04). CONCLUSIONS: Consumption of fruits and vegetables high in specific carotenoids and vitamins may reduce premenopausal breast cancer risk.

Adult↗
PubMed1999

Prospective cohort study of antioxidant vitamin supplement use and the risk of age-related maculopathy.

In a prospective cohort study, the authors examined whether self-selection for antioxidant vitamin supplement use affects the incidence of age-related maculopathy. The study population consisted of 21,120 US male physician participants in the Physicians' Health Study I who did not have a diagnosis of age-related maculopathy at baseline (1982). During an average of 12.5 person-years of follow-up, a total of 279 incident cases of age-related maculopathy with vision loss to 20/30 or worse were confirmed by medical record review. In multivariate analysis, as compared with nonusers of supplements, persons who used vitamin E supplements had a possible but nonsignificant 13% reduced risk of age-related maculopathy (relative risk = 0.87, 95 percent confidence interval (CI) 0.53-1.43), while users of multivitamins had a possible but nonsignificant 10% reduced risk (relative risk = 0.90, 95% CI 0.68-1.19). Users of vitamin C supplements had a relative risk of 1.03 (95% CI 0.71-1.50). These observational data suggest that among persons who self-select for supplemental use of antioxidant vitamin C or E or multivitamins, large reductions in the risk of age-related maculopathy are unlikely. Randomized trial data are accumulating to enable reliable detection of the existence of more plausible small-to-moderate benefits of these agents alone and in combination on age-related maculopathy.

Adult↗
PubMed1999

Birthweight and the risk for type 2 diabetes mellitus in adult women.

BACKGROUND: Previous reports have suggested an association between birthweight and type 2 diabetes mellitus. OBJECTIVE: To investigate the association between birthweight and type 2 diabetes in a large cohort of adult women, taking into account potential explanatory factors in childhood and adult life. DESIGN: Cohort study. Birthweight was ascertained at the end of follow-up. SETTING: The Nurses' Health Study, a cohort of 121,701 U.S. women born from 1921 to 1946 who have been followed since 1976. PARTICIPANTS: 69,526 women in the Nurses' Health Study who were free of diabetes at baseline and reported their own birthweight on the 1992 questionnaire. MEASUREMENT: 2123 cases of confirmed type 2 diabetes diagnosed from 1976 to 1992. RESULTS: Low birthweight was associated with increased risk for type 2 diabetes. Age-adjusted relative risks suggested a reverse J-shape association between birthweight and risk for type 2 diabetes. However, after adjustment for adult body mass index and maternal history of diabetes, an inverse association across the entire range of birthweight became apparent; compared with the reference group, relative risks by ascending birthweight category were 1.83 (95% CI, 1.55 to 2.16) for birthweight less than 5.0 lb, 1.76 (CI, 1.49 to 2.07) for birthweight 5.0 to 5.5 lb, 1.23 (CI, 1.11 to 1.37) for birthweight 5.6 to 7.0 lb, 0.95 (CI, 0.82 to 1.10) for birthweight 8.6 to 10.0 lb, and 0.83 (CI, 0.63 to 1.07) for birthweight of more than 10 lb (P for trend < 0.001). Adjustment for ethnicity, childhood socioeconomic status, and adult lifestyle factors did not substantially alter this association. The association between birthweight and risk for type 2 diabetes was strongest among women whose mothers had no history of diabetes. CONCLUSIONS: Birthweight is inversely associated with risk for type 2 diabetes during adulthood. Examination of prenatal nutrition and other potential in utero determinants of both birthweight and risk for type 2 diabetes may yield new means to prevent type 2 diabetes.

Adult↗
PubMed1999

A retrospective cohort study of cigarette smoking and risk of rheumatoid arthritis in female health professionals.

OBJECTIVE: To study the association of cigarette smoking with risk of rheumatoid arthritis (RA), among 377,481 female health professionals in the Women's Health Cohort Study. METHODS: Subjects completed mailed questionnaires regarding demographics, health habits, including cigarette smoking history, and medical history, including RA diagnosis made by a physician and date of diagnosis. Of 7,697 women who self-reported RA, 3,416 reported seropositive RA. Cox proportional hazards regression models were used to retrospectively assess the associations of smoking intensity and duration with the risk of developing RA or seropositive RA. Cigarette smoking status was treated as a time-varying exposure in these regression models. RESULTS: In multivariate analyses controlling for age, race, education, age at menarche, pregnancy history, menopausal status, and postmenopausal hormone use, duration of smoking was associated with a significantly increased risk of both RA and seropositive RA (both P < 0.01 for trend), after adjusting for smoking intensity. Women who smoked > or =25 cigarettes/day for more than 20 years experienced a 39% increased risk of RA and 49% increased risk of seropositive RA. However, smoking intensity (number of cigarettes/day) was unrelated to risk of RA or seropositive RA (both P = 0.3 for trend), after adjusting for duration of smoking. CONCLUSION: Duration, but not intensity, of cigarette smoking is associated with a modest increased risk of RA in women.

Arthritis, Rheumatoid↗
PubMed1999

Determinants of retinopathy progression in type 1 diabetes mellitus.

PURPOSE: To determine the risk factors for retinopathy progression in type 1 (insulin-dependent) diabetes mellitus in a prospective cohort study. SUBJECTS AND METHODS: Subjects were 485 participants in the Sorbinil Retinopathy Trial, a randomized trial of aldose reductase inhibition among patients aged 18 to 56 years with type 1 diabetes mellitus (duration of 1 to 15 years) and no or only mild retinopathy. Retinopathy progression, assessed by seven-field stereoscopic fundus photography, was defined as worsening by two or more levels on a standardized grading scale at the end of follow-up (median, 41 months). RESULTS: The relative risks for retinopathy progression according to successively greater quintiles of total glycosylated hemoglobin level at baseline, after adjusting for age, diabetes duration, sorbinil assignment, and other variables, were 1.0, 2.0, 1.6, 3.7, and 4.4 (P trend <0.0001). Risk increased with greater baseline diastolic blood pressure: 1.0 for <70 mm Hg, 1.2 for 70 to 79 mm Hg, and 1.8 for > or =80 mm Hg (P for trend = 0.04). Diastolic blood pressure was a significant risk factor for progression in participants with mild baseline retinopathy (P for trend <0.02) but not in those without retinopathy at entry. Systolic blood pressure, by comparison, was not associated with progression. Baseline total cholesterol level was a marginally significant predictor of retinopathy progression when examined as a categorical variable (relative risks for increasing quartiles; 1.0, 1.6, 1.8, 1.9; P for trend = 0.03) but not when it was examined as a continuous variable or when hypercholesterolemic patients were compared with those with normal levels. Furthermore, when cholesterol levels were updated in subsequent visits, it was not a significant predictor of progression, and low density lipoprotein (LDL) cholesterol levels did not predict progression no matter how analyzed. Smoking was not associated with progression of retinopathy. CONCLUSIONS: Levels of hyperglycemia and diastolic blood pressure predicted progression of retinopathy in type 1 diabetes mellitus. We found only a suggestion of an association between total cholesterol level (but not of LDL cholesterol level) and progression of retinopathy; resolution of this issue will require additional studies with larger sample sizes and longer follow-up.

Adult↗
PubMed1999

Vasectomy and subsequent cardiovascular disease in US physicians.

Due to previous animal research suggesting accelerated atherosclerosis following vasectomy, we examined whether vasectomy increases the risk of subsequent cardiovascular disease (CVD), including myocardial infarction (MI), angina pectoris, coronary revascularization, and stroke, in the US Physicians' Health Study. Of 22,071 US male physicians participating in the study, aged 40 to 84 years at entry and free from cardiovascular disease and cancer, 21,028 reported on the 60-month questionnaire whether they had undergone vasectomy prior to randomization. Of the 4546 physicians with vasectomy, 1159 had undergone the procedure at least 15 years before entry. During 258,892 person-years of follow-up, we documented 773 cases of MI (719 nonfatal and 54 fatal), 1907 cases of angina pectoris or coronary revascularization, and 604 confirmed cases of ischemic or hemorrhagic stroke (566 nonfatal and 38 fatal). When compared to men without prior vasectomy, the multivariate relative risk (RR) of total MI adjusted for age and other coronary risk factors was 0.94 (95% confidence interval [CI], 0.77-1.14) among men with vasectomy. Risk estimates for fatal and nonfatal events did not appreciably differ from each other. For angina or coronary revascularization or both, the multivariate relative risk was 0.99 (0.88-1.12) and for total stroke the RR was 0.95 (0.75-1.21). For men who had undergone vasectomy 15 or more years previously, the multivariate relative risks were 0.98 (0.73-1.32) for total MI, 1.17 (0.87-1.57) for total stroke, and 1.12 (0.94-1.35) for angina/revascularization. These results provide reassuring evidence that vasectomy does not materially increase the risk of subsequent cardiovascular disease, even 15 or more years following the procedure.

Cardiovascular Diseases↗
PubMed1999

High body mass index and hypercholesterolemia: risk of hypertensive disorders of pregnancy.

OBJECTIVE: To examine the relationship between pregravid body mass index (BMI), elevated cholesterol level, and the development of hypertensive disorders of pregnancy. METHODS: We studied 15,262 women who gave birth between 1991 and 1995. Pregravid exposures including BMI and self-reported history of elevated cholesterol were ascertained by biennial mailed questionnaires. Gestational hypertension or preeclampsia was confirmed by medical record review according to standard criteria. Proportional hazards analysis was used to adjust for potential confounding variables. RESULTS: We confirmed 216 cases of gestational hypertension and 86 cases of preeclampsia. The risk of gestational hypertension increased as pregravid BMI increased (P < .01). Compared with women with a pregravid BMI of 21-22.9 kg/m2, the relative risk (RR) of gestational hypertension was 1.6 (95% confidence interval [CI] 1.0, 2.3) for women with BMI of 23-24.9 kg/m2, 2.0 (95% CI 1.3, 3.0) for BMI 25-29.9 kg/m2, and 2.6 (95% CI 1.6, 4.4) for BMI over 30 kg/m2. Leaner women (BMI less than 21 kg/m2) had a reduced risk (RR 0.7, 95% CI 0.4, 1.0). For preeclampsia, the RR of women with pregravid BMI over 30 kg/m2 was 2.1 (95% CI 1.0, 4.6) (P for trend 0.09). A history of elevated cholesterol was not associated with the risk of gestational hypertension (RR 0.9, 95% CI, 0.6, 1.4). In contrast, the RR of preeclampsia in women with a history of elevated cholesterol was 2.0 (95% CI 1.2, 3.3). CONCLUSION: Pregravid BMI and hypercholesterolemia could identify women at higher risk for hypertensive disorders during pregnancy.

Adult↗
PubMed1999

A prospective study of alcohol consumption and the risk of age-related macular degeneration.

PURPOSE: Vascular risk factors, including alcohol intake, have been hypothesized to play a role in the development of age-related macular degeneration (AMD). We examined the relationship of alcohol intake with AMD in the Physicians' Health Study (PHS). METHODS: The PHS was a randomized trial of aspirin and beta-carotene among 22,071 U.S. male physicians age 40 to 84 years at entry. A total of 21,041 physicians with complete data on alcohol consumption and no AMD at baseline were included in this analysis. Proportional hazards models were used to estimate relative risks (RR) and 95% confidence interval (CI). RESULTS: During an average follow-up period of 12.5 years, 278 physicians were confirmed by medical record review to have incident AMD resulting in vision loss ( acuity 20/30 or worse). After adjusting for age, randomized treatment assignment, and other potential risk factors, the RR for > or = 1 drink/week versus < 1 drink/week was 0.97 (CI: 0.78-1.21). For categories of alcohol intake, the RRs for those reporting alcohol consumption of < 1 drink/week, 1 drink/week, 2-4 drinks/week, 5-6 drinks/week, and > or = 1 drink/day were 1.00 (referent), 1.00 (0.65-1.55), 0.68 (0.44-1.04), 1.32 (0.89-1.95), and 1.27 (0.93-1.73), respectively. CONCLUSIONS: These prospective data indicate that alcohol intake is not appreciably associated with the risk of incident AMD. However, the width of the confidence intervals are compatible with a possible small effect (reduction or increase) in risk for low to moderate levels of alcohol intake, which warrant further investigation.

Adult↗
PubMed1999

Dietary protein and risk of ischemic heart disease in women.

BACKGROUND: Ingestion of animal protein raises serum cholesterol in some experimental models but not in others, and ecologic studies have suggested a positive association between animal protein intake and risk of ischemic heart disease. Prospective data on the relation of protein intake to risk of ischemic heart disease are sparse. OBJECTIVE: The objective was to examine the relation between protein intake and risk of ischemic heart disease. DESIGN: The study was a prospective cohort study. RESULTS: We examined the association between dietary protein intake and incidence of ischemic heart disease in a cohort of 80082 women aged 34-59 y and without a previous diagnosis of ischemic heart disease, stroke, cancer, hypercholesterolemia, or diabetes in 1980. Intakes of protein and other nutrients were assessed with validated dietary questionnaires. We documented 939 major instances of ischemic heart disease during 14 y of follow-up. After age, smoking, total energy intake, percentages of energy from specific types of fat, and other ischemic heart disease risk factors were controlled for, high protein intakes were associated with a low risk of ischemic heart disease; when extreme quintiles of total protein intake were compared, the relative risk was 0.74 (95% CI: 0.59, 0.94). Both animal and vegetable proteins contributed to the lower risk. This inverse association was similar in women with low- or high-fat diets. CONCLUSIONS: Our data do not support the hypothesis that a high protein intake increases the risk of ischemic heart disease. In contrast, our findings suggest that replacing carbohydrates with protein may be associated with a lower risk of ischemic heart disease. Because a high dietary protein intake is often accompanied by increases in saturated fat and cholesterol intakes, application of these findings to public dietary advice should be cautious.

Adult↗
PubMed1999

Dietary intake of alpha-linolenic acid and risk of fatal ischemic heart disease among women.

BACKGROUND: Experimental studies in laboratory animals and humans suggest that alpha-linolenic acid (18:3n-3) may reduce the risk of arrhythmia. OBJECTIVE: The objective was to examine the association between dietary intake of alpha-linolenic acid and risk of fatal ischemic heart disease (IHD). DESIGN: This was a prospective cohort study. The intake of alpha-linolenic acid was derived from a 116-item food-frequency questionnaire completed in 1984 by 76283 women without previously diagnosed cancer or cardiovascular disease. RESULTS: During 10 y of follow-up, we documented 232 cases of fatal IHD and 597 cases of nonfatal myocardial infarction. After adjustment for age, standard coronary risk factors, and dietary intake of linoleic acid and other nutrients, a higher intake of alpha-linolenic acid was associated with a lower relative risk (RR) of fatal IHD; the RRs from the lowest to highest quintiles were 1.0, 0.99, 0.90, 0.67, and 0.55 (95% CI: 0.32, 0.94; P for trend = 0.01). For nonfatal myocardial infarction there was only a modest, nonsignificant trend toward a reduced risk when extreme quintiles were compared (RR: 0.85; 95% CI: 0.61, 1.19; P for trend = 0.50). A higher intake of oil and vinegar salad dressing, an important source of alpha-linolenic acid, was associated with reduced risk of fatal IHD when women who consumed this food > or =5-6 times/wk were compared with those who rarely consumed this food (RR: 0.46; 95% CI: 0.27, 0.76; P for trend = 0.001). CONCLUSIONS: This study supports the hypothesis that a higher intake of alpha-linolenic acid is protective against fatal IHD. Higher consumption of foods such as oil-based salad dressing that provide polyunsaturated fats, including alpha-linolenic acid, may reduce the risk of fatal IHD.

Adult↗
PubMed1999

Whole-grain consumption and risk of coronary heart disease: results from the Nurses' Health Study.

BACKGROUND: Although current dietary guidelines for Americans recommend increased intake of grain products to prevent coronary heart disease (CHD), epidemiologic data relating whole-grain intake to the risk of CHD are sparse. OBJECTIVE: Our objective was to evaluate whether high whole-grain intake reduces risk of CHD in women. DESIGN: In 1984, 75521 women aged 38-63 y with no previous history of cardiovascular disease or diabetes completed a detailed, semiquantitative food-frequency questionnaire (SFFQ) and were followed for 10 y, completing SFFQs in 1986 and 1990. We used pooled logistic regression with 2-y intervals to model the incidence of CHD in relation to the cumulative average diet from all 3 cycles of SFFQs. RESULTS: During 729472 person-years of follow-up, we documented 761 cases of CHD (208 of fatal CHD and 553 of nonfatal myocardial infarction). After adjustment for age and smoking, increased whole-grain intake was associated with decreased risk of CHD. For increasing quintiles of intake, the corresponding relative risks (RRs) were 1.0 (reference), 0.86, 0.82, 0.72, and 0.67 (95% CI comparing 2 extreme quintiles: 0.54, 0.84; P for trend < 0.001). After additional adjustment for body mass index, postmenopausal hormone use, alcohol intake, multivitamin use, vitamin E supplement use, aspirin use, physical activity, and types of fat intake, these RRs were 1.0, 0.92, 0.93, 0.83, and 0.75 (95% CI: 0.59, 0.95; P for trend = 0.01). The inverse relation between whole-grain intake and CHD risk was even stronger in the subgroup of never smokers (RR = 0. 49 for extreme quintiles; 95% CI: 0.30, 0.79; P for trend = 0.003). The lower risk associated with higher whole-grain intake was not fully explained by its contribution to intakes of dietary fiber, folate, vitamin B-6, and vitamin E. CONCLUSIONS: Increased intake of whole grains may protect against CHD.

Adult↗
PubMed1999

Dietary saturated fats and their food sources in relation to the risk of coronary heart disease in women.

BACKGROUND: Metabolic studies suggest that saturated fatty acids differ in their effects on blood lipids. OBJECTIVE: The objective was to examine the associations between intakes of individual saturated fatty acids and their food sources in relation to the risk of coronary heart disease (CHD). DESIGN: This was a prospective cohort study of 80082 women in the Nurses' Health Study aged 34-59 y. Subjects had no known cardiovascular disease, cancer, hypercholesterolemia, or diabetes, and completed validated food-frequency questionnaires in 1980. RESULTS: During 14 y of follow-up, we documented 939 incident cases of major CHD events. In multivariate analyses in which age, smoking, and other covariates were controlled for, intakes of short- to medium-chain saturated fatty acids (4:0-10:0) were not significantly associated with the risk of CHD. In contrast, intakes of longer-chain saturated fatty acids (12:0-18:0) were each separately associated with a small increase in risk. The multivariate RR for a 1% energy increase from stearic acid was 1.19 (95% CI: 1.02, 1.37). The ratio of polyunsaturated to saturated fat was strongly and inversely associated with CHD risk (multivariate RR for a comparison of the highest with the lowest deciles: 0.58; 95% CI: 0.41, 0.83; P for trend < 0.0001). Conversely, higher ratios of red meat to poultry and fish consumption and of high-fat to low-fat dairy consumption were associated with significantly greater risk. CONCLUSION: A distinction between stearic acid and other saturated fats does not appear to be important in dietary advice to reduce CHD risk, in part because of the high correlation between stearic acid and other saturated fatty acids in typical diets.

Adult↗
PubMed1999

Beta-carotene supplementation: a good thing, a bad thing, or nothing?

Available data from several completed large-scale randomized trials indicate that beta-carotene supplementation for durations up to 12 years has no overall benefit in well-nourished populations on the incidence of cardiovascular disease or the middle-to-late stages of carcinogenesis. Several important questions, however, remain unanswered. The post-trial follow-up of completed trials, together with the results of several ongoing trials of beta-carotene supplementation, will contribute reliable information to the totality of evidence from basic research, animal studies, observational epidemiologic studies, and completed trials, thus allowing more rational clinical decisions for individual patients and policy decisions for the health of the general public.

Antioxidants↗
PubMed1999

Exercise and risk of stroke in male physicians.

BACKGROUND AND PURPOSE: From a physiological perspective, physical activity might be expected to decrease the risk of developing stroke. However, epidemiological studies of physical activity and stroke risk have yielded divergent findings. We therefore sought to examine the association between exercise and stroke risk. METHODS: This was a prospective cohort study of 21 823 men, followed up for an average of 11.1 years. Participants were from the Physicians' Health Study, a randomized trial of low-dose aspirin and beta carotene. Men, aged 40 to 84 years at baseline, were free of self-reported myocardial infarction, stroke, transient ischemic attack, and cancer. At baseline, they reported on the frequency of exercise vigorous enough to work up a sweat. Stroke occurrence was reported by participants and confirmed after medical record review (n=533). We used Cox proportional hazards regression to analyze the data. RESULTS: With adjustment for age, treatment assignment, smoking, alcohol intake, history of angina, and parental history of myocardial infarction, the relative risks of total stroke associated with vigorous exercise <1 time, 1 time, 2 to 4 times, and >/=5 times per week at baseline were 1.00 (referent), 0.79 (95% confidence interval [CI], 0.61 to 1. 03), 0.80 (95% CI, 0.65 to 0.99), and 0.79 (95% CI, 0.61 to 1.03), respectively; P for trend=0.04. In subgroup analyses, the inverse association appeared stronger with hemorrhagic than ischemic stroke. When we additionally adjusted for body mass index, history of hypertension, high cholesterol, and diabetes mellitus, corresponding relative risks for total stroke were 1.00 (referent), 0.81 (95% CI, 0.61 to 1.07), 0.88 (95% CI, 0.70 to 1.10), and 0.86 (95% CI, 0.65 to 1.13), respectively; P for trend=0.25. CONCLUSIONS: Exercise vigorous enough to work up a sweat is associated with decreased stroke risk in men. In the present study, the inverse association with physical activity appeared to be mediated through beneficial effects on body weight, blood pressure, serum cholesterol, and glucose tolerance. Apart from its favorable influences on these variables, physical activity had no significant residual association with stroke incidence.

Adult↗
PubMed1999

Prospective study of aspirin use and risk of stroke in women.

BACKGROUND AND PURPOSE: In secondary prevention, aspirin reduces risk of ischemic stroke. In primary prevention of stroke, however, the role of aspirin is uncertain, especially in women. METHODS: In 1980, 79 319 women in the Nurses' Health Study cohort, 34 to 59 years of age and free of diagnosed cardiovascular disease, cancer, and rheumatoid arthritis, completed questionnaires that included information on aspirin use. Data on aspirin use were updated in 1982, 1984, and 1988. By 1994, after 994 231 person-years of follow-up, 503 incident strokes (295 ischemic strokes, 100 subarachnoid hemorrhages, 52 intraparenchymal hemorrhages, and 56 strokes of undetermined type) were documented. RESULTS: There was no clear relationship between aspirin use and risk of total stroke; risk was slightly reduced among women who took 1 to 6 aspirin per week and slightly increased among women who took 7 or more aspirin per week. Women who took 1 to 6 aspirin per week had a lower risk of large-artery occlusive infarction compared with women who reported no aspirin use; after simultaneous adjustment for other cardiovascular risk factors and selected nutrients, the multivariate relative risk was 0.50 (95% CI 0.29 to 0.85, P=0.01). Women who took 15 or more aspirin per week had an excess risk of subarachnoid hemorrhage; the multivariate relative risk was 2.02 (95% CI 1.04 to 3.91, P for trend=0.02). The reduction in large-artery occlusive infarction with aspirin was of greater magnitude for older, hypertensive, or smoking women than for younger, nonhypertensive, or nonsmoking women; the elevation in subarachnoid hemorrhage with aspirin was also more apparent for older or hypertensive women than for younger or nonhypertensive women. Aspirin use was not associated with risk of other subtypes of stroke. CONCLUSIONS: These prospective data indicate that women who take 1 to 6 aspirin per week have a reduced risk of large-artery occlusive infarction, but those who use 15 or more aspirin per week have an increased risk of subarachnoid hemorrhage. This observational study suggests benefits of aspirin for ischemic stroke with low frequency of use and hazards for hemorrhagic stroke with high frequency of use, particularly among older or hypertensive women. Thus, the effect on total stroke will depend on the dose of aspirin and the distribution of stroke subtypes and risk factors in the population.

Adult↗
PubMed1999

Prospective study of calcium, potassium, and magnesium intake and risk of stroke in women.

BACKGROUND AND PURPOSE: High intakes of calcium, potassium, and magnesium have been hypothesized to reduce risks of cardiovascular disease, but only a few prospective studies have examined intakes of these cations in relation to risk of stroke. METHODS: In 1980, 85 764 women in the Nurses' Health Study cohort, aged 34 to 59 years and free of diagnosed cardiovascular disease and cancer, completed dietary questionnaires from which we calculated intakes of calcium, potassium, and magnesium. By 1994, after 1.16 million person-years of follow-up, 690 incident strokes (129 subarachnoid hemorrhages, 74 intraparenchymal hemorrhages, 386 ischemic strokes, and 101 strokes of undetermined type) had been documented. RESULTS: Intakes of calcium, potassium, and magnesium were each inversely associated with age- and smoking-adjusted relative risks of ischemic stroke, excluding embolic infarction of nonatherogenic origin (n=347). Adjustment for other cardiovascular risk factors, including history of hypertension, attenuated these associations, particularly for magnesium intake. In a multivariate analysis, women in the highest quintile of calcium intake had an adjusted relative risk of ischemic stroke of 0.69 (95% CI, 0.50 to 0.95; P for trend=0.03) compared with those in the lowest quintile; for potassium intake the corresponding relative risk was 0.72 (95% CI, 0.51 to 1.01; P for trend=0.10). Further simultaneous adjustment for calcium and potassium intake suggested an independent association for calcium intake. The association of risk with calcium intake did not appear to be log linear; the increase in risk was limited to the lowest quintile of intake, and intakes > approximately 600 mg/d did not appear to reduce risk of stroke further. The inverse association with calcium intake was stronger for dairy than for nondairy calcium intake. Intakes of calcium, potassium, and magnesium were not related to risk of other stroke subtypes. CONCLUSIONS: Low calcium intake, and perhaps low potassium intake, may contribute to increased risk of ischemic stroke in middle-aged American women. It remains possible that women in the lowest quintile of calcium intake had unknown characteristics that made them susceptible to ischemic stroke.

Adult↗