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Biomedical subjects

J E Buring

Publications and source records attributed to J E Buring.

At least 109 records · Page 6Linked to original sources
PubMed1994

The benefits of aspirin in acute myocardial infarction. Still a well-kept secret in the United States.

Acute myocardial infarction (MI) remains far and away the leading cause of death in the United States, and is responsible for approximately 500,000 annual fatalities. However, mortality due to MI has declined substantially in recent decades, owing to advances in treatment as well as prevention. Low-dose aspirin as well as thrombolytic therapy given during acute evolving MI each decrease mortality by about one quarter. Both therapies remain underutilized in the United States. Aspirin can be given to virtually all patients, has a far more favorable safety profile than thrombolysis, and confers a comparable benefit at a small fraction of the cost of thrombolytic agents. The more widespread use of aspirin in acute MI is one of the most important and timely clinical challenges in the United States.

Aspirin↗
PubMed1994

Randomized trials of primary prevention of cardiovascular disease in women. An investigator's view.

In recent years, increasing attention has focused on the need for more research to be conducted in women on health issues directly relevant to women. No one would disagree that the need for such studies is both crucial and timely. However, while the need for more research in women is urgent, the planning and conduct of such studies must always be driven by good science. Specifically, investigations in women may have unique and important scientific and logistic problems which must be recognized and addressed. However, if the trials are well designed and conducted, they will provide a sound and reliable body of data upon which to base rational clinical decision making and public health recommendations for women from women. These general issues are discussed in the context of a particular trial, the Women's Health Study, a randomized trial of the risks and benefits of low-dose aspirin, beta-carotene and vitamin E in the primary prevention of cardiovascular disease and cancer among healthy women.

Aspirin↗
PubMed1994

Trans-fatty acids intake and risk of myocardial infarction.

BACKGROUND: Concern that trans-fatty acids formed in the partial hydrogenation of vegetable oils may increase the risk of coronary disease has existed for several decades, but direct evidence on this relation in humans is limited. METHODS AND RESULTS: With a case-control design, we studied the association between intake of trans-fatty acids and a first acute myocardial infarction among 239 patients admitted to one of six hospitals in the Boston area and 282 population control subjects. Intake of trans-fatty acids was estimated using a previously validated food frequency questionnaire. After adjustment for age, sex, and energy intake, intake of trans-fatty acids was directly related to risk of myocardial infarction (relative risk for highest compared with lowest quintile, 2.44; 95% confidence interval, 1.42, 4.19; for trend P < .0001). This relation remained highly significant after adjustment for established coronary risk factors, multivitamin use, and intake of saturated fat, monounsaturated fat, linoleic acid, dietary cholesterol, vitamins E and C, carotene, and fiber. Intake of margarine--the major source of trans-isomers--was significantly associated with risk of myocardial infarction. CONCLUSIONS: These data support the hypothesis that intake of partially hydrogenated vegetable oils may contribute to the risk of myocardial infarction.

Boston↗
PubMed1994

The use of vitamin supplements and the risk of cataract among US male physicians.

OBJECTIVES: The purpose of this study was to examine prospectively the association between reported use of vitamin supplements and risk of cataract and cataract extraction. METHODS: The study population consisted of 17,744 participants in the Physicians' Health Study, a randomized trial of aspirin therapy and beta-carotene among US male physicians 40 to 84 years of age in 1982 who did not report cataract at baseline and provided complete information about vitamin supplementation and other risk factors for cataract. Self-reports of cataract and cataract extraction were confirmed by medical record review. RESULTS: During 60 months of follow-up, there were 370 incident cataracts and 109 cataract extractions. In comparison with physicians who did not use any supplements, those who took only multivitamins had a relative risk of cataract of 0.73 after adjustment for other risk factors. For cataract extraction, the corresponding relative risk was 0.79. Use of vitamin C and/or E supplements alone was not associated with a reduced risk of cataract, but the size of this subgroup was small. CONCLUSIONS: These data suggest that men who took multivitamin supplements tended to experience a decreased risk of cataract and support the need for rigorous testing of this hypothesis in large-scale randomized trials in men and women.

Adult↗
PubMed1994

Confirmation of self-reported cataract in the Physicians' Health Study.

Large-scale prospective studies of disease development often rely on self-reported data. To assess the accuracy of self-reports of cataract, we compared the self-reports with medical record data obtained from diagnosing ophthalmologists and optometrists for participants in the Physicians' Health Study, a randomized trial of aspirin and beta-carotene among 22,071 male U.S. physicians aged 40-84 years. A report of cataract, defined as a positive response to a question about whether cataract had ever been diagnosed in either eye and the date of diagnosis, was found to be a very good indicator of lens opacification but was not a good indicator of an incident, age-related opacity that reduced visual acuity. These results indicate that in large prospective studies of clinically significant cataract, where examination of all study participants is not feasible and self-reported data are used, additional documentation to supplement the self-reports should be obtained and strict diagnostic criteria applied to minimize the likely effects of misclassification.

Adult↗
PubMed1994

Aspirin in the primary prevention of cardiovascular disease.

The ability of aspirin to reduce cardiovascular disease risks has been tested in randomized trials in a wide range of patient categories. There are clear benefits of aspirin on nonfatal myocardial infarction, nonfatal stroke, and vascular death among patients with prior manifestations of cardiovascular disease, such as myocardial infarction, unstable angina, and stroke. Aspirin is also beneficial to those in the acute phase of evolving myocardial infarction. In primary prevention, there is a clear reduction in myocardial infarction in men. A large-scale primary prevention trial in women is presently underway.

Aspirin↗
PubMed1993

Moderate alcohol intake, increased levels of high-density lipoprotein and its subfractions, and decreased risk of myocardial infarction.

BACKGROUND: Previous studies have suggested that moderate alcohol intake exerts a protective effect against coronary heart disease. Alterations in plasma lipoprotein levels represent one plausible mechanism of this apparent protective effect. METHODS: We therefore examined the interrelation among alcohol consumption, plasma lipoprotein levels, and the risk of myocardial infarction in 340 patients who had had myocardial infarctions and an equal number of age- and sex-matched controls. The case patients were men or women less than 76 years of age with no history of coronary disease who were discharged from one of six hospitals in the Boston area with a diagnosis of a confirmed myocardial infarction. Alcohol consumption was estimated by means of a food-frequency questionnaire. RESULTS: We observed a significant inverse association between alcohol consumption and the risk of myocardial infarction (P for trend, < 0.001 after control for known coronary risk factors). In multivariate analyses, the relative risk for the highest intake category (subjects who consumed three or more drinks per day) as compared with the lowest (those who had less than one drink a month) was 0.45 (95 percent confidence interval, 0.26 to 0.80). The levels of total high-density lipoprotein cholesterol (HDL) and its HDL2 and HDL3 subfractions were strongly associated with alcohol consumption (P for trend, < 0.001 for each). The addition of HDL or either of its subfractions to the multivariate model substantially reduced the inverse association between alcohol intake and myocardial infarction, whereas the addition of the other plasma lipid measurements did not materially alter the relation. CONCLUSIONS: These data confirm the inverse association of moderate alcohol intake with the risk of myocardial infarction and support the view that the effect is mediated, in large part, by increases in both HDL2 and HDL3.

Aged↗
PubMed1993

Modification of increasing systolic blood pressure in the elderly during the 1980s.

The authors examined whether changing attitudes and approaches to modifying blood pressure during the 1980s affected the previously described pattern of increasing systolic blood pressure in the elderly which continues through the ninth decade of life. In 1982-1983, a door-to-door census identified 4,497 community-dwelling residents of East Boston, Massachusetts aged 65 and over, of whom 3,657 had baseline blood pressure assessments. Follow-up blood pressure assessments occurred in 1985-1986 and in 1988-1989. Cross-sectionally, the relation of age with systolic blood pressure was quadratic with levels predicted to increase until about age 84 after which they were lower among oldest-old survivors. Longitudinally, mean age-sex-adjusted systolic blood pressure was 3.3 mmHg lower in 1985-1986 compared with 1982-1983 (95 percent confidence interval (CI) 2.4-4.2 mmHg) and 10.6 mmHg lower in 1988-1989 compared with 1982-1983 (95 percent CI 9.5-11.7 mmHg). Utilization of antihypertension medications increased over time and accounted for some, but not all, of the observed decreases in systolic blood pressure. Large shifts occurred in the use of specific antihypertension medications including increases in use of angiotensin converting enzyme inhibitors and calcium entry blockers and decreases in use of thiazide diuretics. Previously described trends for increasing systolic blood pressure in the elderly were reversed during the 1980s when the continued decline in cardiovascular mortality was greatest among the elderly.

Age Factors↗
PubMed1993

Low-dose aspirin and incidence of colorectal tumors in a randomized trial.

BACKGROUND: Laboratory, clinical, and epidemiologic studies have recently suggested that regular use of aspirin can reduce colorectal cancer incidence or mortality. However, observational epidemiologic analyses have had limited opportunity to control for confounding bias or to specify aspirin doses used. PURPOSE: Our purpose was to examine the relationship between regular use of low-dose aspirin and incidence of invasive and noninvasive colorectal tumors by utilizing data from the Physicians' Health Study, a randomized, double-blinded, placebo-controlled trial of aspirin and beta carotene. We also attempted to determine whether invasive cancers among aspirin users were associated with rectal bleeding and early stage at diagnosis. METHODS: The Physicians' Health Study includes 22071 U.S. male physicians. The aspirin arm was terminated in 1988 after a mean follow-up of 5 years. Stage at diagnosis and signs and/or symptoms during presentation were abstracted from medical records. Cox proportional hazards models were used to estimate relative risk (RR), 95% confidence intervals (CIs), and the association between aspirin and bleeding. Differences between aspirin and placebo groups in tumor risk over time were visualized with Kaplan-Meier curves. We assessed the association between aspirin and stage at diagnosis with a Mann-Whitney rank sum statistic for non-parametric comparison of two ordinal distributions. RESULTS: The RR of developing colorectal cancer for aspirin compared with placebo was 1.15 (95% CI = 0.80-1.65). For in situ cancers and polyps, the RR was 0.86 (95% CI = 0.68-1.10). There was no significant trend for decreasing RR by year of follow-up for invasive cancers (P = .09) or noninvasive tumors (P = .96). Aspirin and placebo groups did not differ in stage or prevalence of rectal bleeding at diagnosis. CONCLUSIONS: Regular aspirin use, at a dose adequate for preventing myocardial infarction, was not associated with a substantial reduction in the incidence of colorectal cancer during 5 years of randomized treatment and follow-up. A small decrease in polyps in the aspirin group could not be reliably distinguished from a chance association. Our results suggest that among low-dose aspirin users, (a) colorectal cancer mortality is not likely to be reduced by earlier detection and (b) incidence is not likely to be increased due to aspirin-induced gastrointestinal bleeding. IMPLICATIONS: The potential for a benefit from higher doses of aspirin or longer duration of use should be addressed by more detailed observational epidemiologic studies and prevention trials with longer follow-up of randomized participants.

Adult↗
PubMed1993

Antiplatelet therapy and risk of stroke.

Antiplatelet therapy, especially with aspirin, reduces the risks of occlusive vascular disease, including ischemic stroke. In an overview of 25 trials of antiplatelet therapy in patients with prior cardiovascular disease, antiplatelet treatment reduced subsequent nonfatal stroke by 27% (P = 0.0001), nonfatal myocardial infarction by 32% (P = 0.0001), and all vascular deaths by 15% (P = 0.0003), with no evidence that other antiplatelet agents were more effective than aspirin, or that higher aspirin doses (900 to 1500 mg daily) were more effective than 300 mg, the lowest daily dose tested. If begun during the acute phase of myocardial infarction, aspirin reduces nonfatal stroke by 46% (P < 0.01) and vascular deaths by 23% (P < 0.00001) after 5 weeks. In primary prevention, currently available data are inconclusive regarding the effect of aspirin therapy on stroke. However, any potential benefit on ischemic stroke must be weighed against the possibility that aspirin could increase the risk of the less common, but clinically more severe, strokes of hemorrhagic etiology.

Aspirin↗
PubMed1993

Height and incidence of cardiovascular disease in male physicians.

BACKGROUND: An inverse association between height and risk of coronary heart disease (CHD) has been reported in several case-control and cohort studies, but the reasons for the association remain uncertain. We evaluated this association among 22,071 male physicians, a population homogeneous for high educational attainment and socioeconomic status in adulthood. METHODS AND RESULTS: The study population was comprised of participants in the Physicians' Health Study, a randomized, double-blind, placebo-controlled trial of low-dose aspirin and beta-carotene in the primary prevention of cardiovascular disease and cancer among US male physicians, aged 40 to 84 years, in 1982. Participants were classified into five height categories at study entry, from shortest to tallest, and were followed an average of 60.2 months to determine the incidence of myocardial infarction (MI), stroke, and death from cardiovascular disease. Men in the tallest (> or = 73 in. or 185.4 cm) compared with the shortest (< or = 67 in. or 170.2 cm) height category had a 35% lower risk of MI (relative risk, 0.65; 95% confidence interval, 0.44 to 0.99; P = .04), after adjusting for known cardiovascular risk factors. Further, a marginally significant inverse trend (P trend = .05) across the height categories was observed. Although the relationship was not strictly linear, for every inch of added height, there was an approximate 2% to 3% decline in risk of MI. In contrast, men in the tallest compared with the shortest height category had only small and nonsignificant decreases in risk of stroke and cardiovascular death. While no significant trend in risks of these end points across the height categories was observed, the numbers of events for these end points were far less than for MI, and thus the confidence intervals were wide. CONCLUSIONS: These data indicate that height is inversely associated with subsequent risk of MI. At this time, a few mechanisms are plausible, but none are convincing. Other epidemiological and basic research efforts are needed to explore a variety of physiological correlates of height that may be responsible for mediating the height-MI association. In the meantime, while height is not modifiable, it is easy to measure and may be useful to evaluate CHD disease risk profiles and target lifestyle interventions.

Adjuvants, Immunologic↗
PubMed1992

A prospective study of cigarette smoking and risk of cataract in men.

OBJECTIVE: To examine the association between cigarette smoking and the incidence of cataract. DESIGN, SETTING, AND PARTICIPANTS: The design was a prospective cohort study using data from the Physicians' Health Study, a randomized trial of aspirin and beta carotene among 22,071 US male physicians aged 40 to 84 years that began in 1982. This analysis includes the 17,824 physicians who did not report cataract at baseline and did provide complete risk factor information. Based on information reported at baseline, 10% were current smokers, 39% were past smokers, and 51% were never smokers. MAIN OUTCOME MEASURE: An incident cataract was defined as a self-report confirmed by medical record review to have been first diagnosed after randomization, age-related in origin, and responsible for a decrease in best corrected visual acuity to 20/30 or worse. MAIN RESULTS: During 60 months of follow-up, 557 incident cataracts among 371 participants were confirmed. Compared with never smokers, current smokers of 20 or more cigarettes per day had a statistically significant increase in the risk of cataract (relative risk [RR], 2.16; 95% confidence interval [Cl], 1.46 to 3.20; P less than .001). Similar results were obtained after simultaneously controlling for other potential cataract risk factors in a logistic regression model (RR, 2.05; 95% Cl, 1.38 to 3.05; P less than .001). Among the 557 eyes with cataract, nuclear sclerotic changes were present in 442 while posterior subcapsular changes were present in 204. After controlling for other potential cataract risk factors, current smokers of 20 or more cigarettes per day had statistically significant increases in nuclear sclerosis (RR, 2.24; 95% Cl, 1.47 to 3.41; P less than .001) and posterior subcapsular (RR, 3.17; 95% Cl, 1.81 to 5.53; P less than .001) cataract. Past smokers had an elevated risk of posterior subcapsular (RR, 1.44; 95% Cl, 0.97 to 2.13; P = .07) but not nuclear sclerosis cataract. For current smokers of fewer than 20 cigarettes per day, no increased risks were observed of total, nuclear sclerosis, or posterior subcapsular cataract. CONCLUSIONS: These data provide support for the hypothesis that cigarette smoking increases the risk of developing both nuclear sclerosis and posterior subcapsular cataract.

Adult↗