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M J Stampfer

Publications and source records attributed to M J Stampfer.

At least 361 records · Page 20Linked to original sources
PubMed1993

The reproducibility and validity of a self-administered semiquantitative food frequency questionnaire in subjects from South Dakota and Wyoming.

Most validation studies of food frequency questionnaires have been done in populations capable of reporting their diet with unusual accuracy. In this study of ranchers and subjects selected at random, we compared nutrient intakes as assessed with multiple diet records with those assessed with a self-administered food frequency questionnaire (the Harvard-Willett instrument with 116 food items). One hundred thirty-eight subjects from South Dakota and Wyoming, 64 males and 74 females, completed at least one food frequency questionnaire and multiple 1-day diet records (mean = 5 days) during a 6-month to 1-year period. Of invited subjects, 88% participated; 59% of participants had a high school education or less. For 22 dietary nutrients (excluding supplements) and alcohol, the median crude correlation between intakes based on diet records and the food frequency questionnaire completed before the diet records was 0.42; after adjustment for energy, age, and sex, and after correction for attenuation in the correlation coefficients due to error from a limited number of diet records, the median correlation was 0.52. Correlations for men and women were similar. The validity of the food frequency questionnaire in this population was similar to that reported previously and supports the use of self-administered food frequency questionnaires in studies of general populations.

Data Collection↗
PubMed1993

A cross-sectional study of endogenous tissue plasminogen activator, total cholesterol, HDL cholesterol, and apolipoproteins A-I, A-II, and B-100.

Elevated levels of endogenous tissue-type plasminogen activator (t-PA) appear to be a marker for preclinical atherosclerosis. At present, however, data describing potential relations between plasma t-PA level and established lipid risk factors for coronary atherosclerosis are sparse. To explore these potential relations, we measured plasma levels of t-PA antigen (t-PA:ag) in 633 apparently healthy men in the Physicians' Health Study as well as total cholesterol, high-density lipoprotein (HDL) cholesterol, HDL2 cholesterol, HDL3 cholesterol, and apolipoproteins A-I, A-II, and B-100. Overall, plasma t-PA:ag levels were inversely correlated with HDL cholesterol (r = -.1616, P < .0005), HDL2 cholesterol (r = -.1632, P < .0005), and HDL3 cholesterol (r = -.0927, P = .019). In stratified analyses, the inverse association between t-PA:ag and HDL cholesterol was present among frequent (P trend = .002) and infrequent (P trend = .004) consumers of alcohol as well as among the subgroups of frequent exercisers (P trend < .001), men in the lower half of body mass index (P trend = .001), and nonsmokers (P trend < .001). In contrast, there was no association between t-PA:ag and total cholesterol (r = .0219, P = .58), whereas relations of t-PA:ag with apolipoproteins A-I, A-II, and B-100 were minimal and of borderline significance. These data indicate that plasma levels of endogenous t-PA:ag are inversely related to HDL cholesterol as well as HDL2 and HDL3 cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Cigarette smoking and the risk of diabetes in women.

OBJECTIVES: Noninsulin-dependent diabetes mellitus, a major risk factor for cardiovascular disease, is prevalent in more than 12 million Americans. A voluminous amount of data demonstrates that cigarette smoking is an important cause of cancer and coronary heart disease. However, the association between cigarette smoking and the risk of diabetes is virtually unexplored, especially in women. METHODS: We examined the association between smoking and the incidence of noninsulin-dependent diabetes mellitus among 114,247 female nurses who were free of diabetes, cardiovascular disease, and cancer in 1976. We collected exposure information and disease status prospectively for 12 years from biennially self-administered questionnaires. RESULTS: Current smokers had an increased risk of diabetes, and we observed a significant dose-response trend for higher risk among heavier smokers. During 1,277,589 person-years of follow-up, 2333 women were clinically diagnosed with diabetes. The relative risk of diabetes, adjusted for obesity and other risk factors, was 1.42 among women who smoked 25 or more cigarettes per day compared with nonsmokers. CONCLUSIONS: These data suggest that cigarette smoking may be an independent, modifiable risk factor for noninsulin-dependent diabetes mellitus.

Adult↗
PubMed1993

Comparison of diets of diabetic and nondiabetic women.

OBJECTIVE: To assess the dietary habits of diabetic women. RESEARCH DESIGN AND METHODS: Participants in the Nurses Health Study, a cohort of 121,700 registered female nurses, were followed since 1976. We compared the usual dietary intakes of women who had been diagnosed with diabetes mellitus by 1980 and age-matched nondiabetic control women; diets of these women were assessed in 1980 and 1984 by a semiquantitative food frequency questionnaire. The study examined 162 IDDM women and 738 NIDDM women. Similar comparisons were made for 429 women who developed NIDDM between 1980 and 1984. RESULTS: Although differences were small, women with IDDM in 1984 and women with NIDDM in 1980 and 1984 consumed less energy from carbohydrates, especially from sucrose, and more energy from protein and fat than did control women. Similar results were also found in 1984 for the 429 women who developed NIDDM between 1980 and 1984. In 1980, energy from nonsucrose carbohydrate was slightly higher in both IDDM and NIDDM women than in the control women. However, in 1984, using a dietary questionnaire designed to assess more complete dietary intake, less consistent results were obtained. Diabetic women tended to avoid desserts and sweets, sugar-containing beverages, and alcoholic beverages but consumed more meat and meat products. Intakes of foods high in complex carbohydrates (e.g., bread, rice, pasta, and potatoes) were similar between diabetic and control women. CONCLUSIONS: The results suggest that these diabetic women did not consume the high-carbohydrate, low-fat diets that the American Diabetes Association has been recommending over the past decade.

Adult↗
PubMed1992

Anticardiolipin antibodies and the risk for ischemic stroke and venous thrombosis.

OBJECTIVE: To determine whether the presence of anticardiolipin antibodies is a risk factor for ischemic stroke and venous thrombosis in healthy adult men. DESIGN: A nested, case-control study in a prospective cohort. SETTING: A nationwide study of physicians. PARTICIPANTS: The study sample was drawn from the Physicians' Health Study, a randomized, double-blind, placebo-controlled trial of aspirin and beta-carotene in 22,071 male physicians. At entry, 68% of the participants submitted plasma samples that were subsequently frozen at -80 degrees C. During 60.2 months of follow-up, follow-up for nonfatal outcomes was 99.7% complete and ascertainment of fatal outcomes was 100% complete. We identified men with documented ischemic stroke, deep venous thrombosis of the leg, or pulmonary embolus and for whom a plasma sample was available. A control was matched by age, smoking history, and length of follow-up to each of the 100 patients with ischemic stroke and the 90 patients with deep venous thrombosis or pulmonary embolus. MEASUREMENTS: Plasma samples were assessed for IgG anticardiolipin antibodies by enzyme-linked immunosorbent assay. The mean anticardiolipin antibody titers of the case patients in the two diagnostic groups (ischemic stroke; venous thrombosis or pulmonary embolus) were compared with those of the control groups, and relative risks were calculated for patients in increasing percentile categories of anticardiolipin antibodies by conditional logistic regression. RESULTS: The anticardiolipin antibody titers were higher in case patients with deep venous thrombosis and pulmonary embolus than in their matched controls (P = 0.01). Persons with anticardiolipin antibody titers above the 95th percentile had a relative risk for developing deep venous thrombosis or pulmonary embolus of 5.3 (95% CI, 1.55 to 18.3; P = 0.01). The anticardiolipin antibody titers in case patients with ischemic stroke and controls were not significantly different (P > 0.2), and no clear trend of higher risks among those with elevated levels of anticardiolipin antibodies was observed. CONCLUSION: An anticardiolipin antibody level above the 95th percentile is an important risk factor for deep venous thrombosis or pulmonary embolus but not for ischemic stroke in healthy adult men.

Adult↗
PubMed1992

Dietary fat and fiber in relation to risk of breast cancer. An 8-year follow-up.

OBJECTIVE: To address the hypotheses that dietary fat increases and fiber decreases the risk of breast cancer. DESIGN: Prospective cohort study with dietary assessment at baseline, using a validated, self-administered food frequency questionnaire. SETTING/PARTICIPANTS: 89,494 women in the Nurses' Health Study who were 34 through 59 years of age in 1980 and who were followed up for 8 years (> 95% complete). RESULTS: 1439 incident cases of breast cancer were diagnosed, including 774 among postmenopausal women. After adjustment for age, established risk factors, and total energy intake, we observed no evidence of any positive association between total fat intake and breast cancer incidence (relative risks [RRs] for increasing quintiles of fat intake were 1.0, 0.85, 0.96, 0.91, and 0.90; 95% confidence interval for highest vs lowest quintile, 0.77 to 1.07). Among postmenopausal women alone, corresponding RRs were 1.0, 0.89, 1.00, 0.95, and 0.91. Comparing extreme deciles of total fat intake (> or = 49% vs < 29% of total energy intake), the RR was 0.86 (95% confidence interval, 0.67 to 1.08). A similar absence of any positive association was observed without adjustment for energy intake; for tumors less than 2 cm as well as 2 cm or greater in diameter; for saturated, monounsaturated, and polyunsaturated fat; and after excluding the first 4 years of follow-up. Also, we found no suggestion of any positive association when using a more detailed and precise dietary questionnaire completed in 1984 (666 subsequent cases), even when women consuming less than 25% of energy from fat were used as the comparison group. No suggestion of a protective effect of dietary fiber was observed (RRs for increasing quintiles were 1.0, 0.95, 0.93, 1.02, and 1.02). CONCLUSIONS: These data provide evidence against both an adverse influence of fat intake and a protective effect of fiber consumption by middle-aged women on breast cancer incidence over 8 years. Nevertheless, the positive association between intake of animal fat and risk of colon cancer observed in many studies provides ample reason to limit this source of energy.

Adult↗
PubMed1992

A prospective study of cigarette smoking and risk of cataract surgery in women.

OBJECTIVE: To examine prospectively the association between cigarette smoking and the risk of cataract extraction in women. DESIGN: Prospective cohort study beginning in 1980 with 8 years of follow-up. SETTING: United States, multistate. PARTICIPANTS: Registered nurses 45 to 67 years of age and free of diagnosed cancer. There were 50,828 women included in 1980 and others were added as they became 45 years of age. MAIN OUTCOME MEASURE: Incidence of senile cataract extraction. RESULTS: We documented 493 incident senile cataracts diagnosed and extracted during 470,302 person-years of follow-up. The age-adjusted relative risk (RR) among women who smoked at least 65 pack-years was 1.63 (95% confidence interval [Cl], 1.18 to 2.26; P for trend, .02). A similar increase in RR was noted when smoking was assessed in terms of number of cigarettes currently smoked or number of cigarettes smoked by past smokers. Results were also similar after adjusting for other potential risk factors for cataract. Smoking was also strongly associated with posterior subcapsular cataract specifically (RR, 2.59; 95% Cl, 1.49 to 4.50 for greater than or equal to 65-pack-year smokers relative to nonsmokers. CONCLUSION: Smoking appears to increase the risk of cataract extraction.

Aged↗
PubMed1992

A prospective study of plasma homocyst(e)ine and risk of myocardial infarction in US physicians.

OBJECTIVE: To assess prospectively the risk of coronary heart disease associated with elevated plasma levels of homocyst(e)ine. DESIGN: Nested case-control study using prospectively collected blood samples. SETTING: Participants in the Physicians' Health Study. PARTICIPANTS: A total of 14,916 male physicians, aged 40 to 84 years, with no prior myocardial infarction (MI) or stroke provided plasma samples at baseline and were followed up for 5 years. Samples from 271 men who subsequently developed MI were analyzed for homocyst(e)ine levels together with paired controls, matched by age and smoking. MAIN OUTCOME MEASURE: Acute MI or death due to coronary disease. RESULTS: Levels of homocyst(e)ine were higher in cases than in controls (11.1 +/- 4.0 [SD] vs 10.5 +/- 2.8 nmol/mL; P = .03). The difference was attributable to an excess of high values among men who later had MIs. The relative risk for the highest 5% vs the bottom 90% of homocyst(e)ine levels was 3.1 (95% confidence interval, 1.4 to 6.9; P = .005). After additional adjustment for diabetes, hypertension, aspirin assignment, Quetelet's Index, and total/high-density lipoprotein cholesterol, this relative risk was 3.4 (95% confidence interval, 1.3 to 8.8) (P = .01). Thirteen controls and 31 cases (11%) had values above the 95th percentile of the controls. CONCLUSIONS: Moderately high levels of plasma homocyst(e)ine are associated with subsequent risk of MI independent of other coronary risk factors. Because high levels can often be easily treated with vitamin supplements, homocyst(e)ine may be an independent, modifiable risk factor.

Adult↗
PubMed1992

Nutrient intake and cataract extraction in women: a prospective study.

OBJECTIVE: To examine prospectively the association between dietary intake of vitamins C and E, carotene, and riboflavin and cataract extraction in women. DESIGN: Prospective cohort study beginning in 1980 with eight years of follow up. SETTING: 11 states of the United States. PARTICIPANTS: Female registered nurses who were 45 to 67 years of age. 50,828 women were included in 1980 and others were added as they became 45 years of age. MAIN OUTCOME MEASURE: Incidence of extraction of senile cataracts. RESULTS: 493 cataracts were extracted during 470,302 person years of follow up. Intake of carotene and vitamin A was inversely associated with cataract: in multivariate analyses, women in the highest fifth of total vitamin A intake (excluding supplements) had a 39% lower risk of cataract relative to women in the lowest fifth (relative risk 0.61; 95% confidence interval 0.45 to 0.81). Neither riboflavin nor dietary vitamins E or C were associated with cataract in a multivariate analysis. Among specific food items spinach (rather than carrots, the greatest source of beta carotene) was most consistently associated with a lower relative risk. The risk of cataract was 45% lower among women who used vitamin C supplements for 10 or more years(relative risk 0.55 (0.32 to 0.96)), but no association was noted for multivitamin intake. CONCLUSION: Dietary carotenoids, although not necessarily beta carotene, and long term vitamin C supplementation may decrease the risk of cataracts severe enough to require extraction.

Aged↗
PubMed1992

Low-dose aspirin and subsequent peripheral arterial surgery in the Physicians' Health Study.

In the US Physicians' Health Study the early termination of the aspirin arm has provided the opportunity to test the hypothesis that low-dose aspirin (325 mg on alternate days) might affect the subsequent occurrence of peripheral arterial surgery. In the study, a randomised double-blind placebo-controlled trial among 22,071 healthy US male physicians aged 40-84, there were, during an average of 60.2 months of treatment and follow-up, 56 participants who underwent peripheral arterial surgery (20 aspirin, 36 placebo). The relative risk of peripheral artery surgery in the aspirin group was 0.54 (95% confidence intervals 0.30-0.95; p = 0.03). These data indicate that chronic administration of low-dose aspirin to apparently healthy men reduced the need for peripheral arterial surgery.

Adult↗
PubMed1992

A prospective study of exercise and incidence of diabetes among US male physicians.

OBJECTIVE: To examine prospectively the association between regular exercise and the subsequent development of non-insulin-dependent diabetes mellitus (NIDDM). DESIGN: Prospective cohort study including 5 years of follow-up. PARTICIPANTS: 21,271 US male physicians participating in the Physicians' Health Study, aged 40 to 84 years and free of diagnosed diabetes mellitus, myocardial infarction, cerebrovascular disease, and cancer at baseline. Morbidity follow-up was 99.7% complete. MAIN OUTCOME MEASURE: Incidence of NIDDM. RESULTS: At baseline, information was obtained about frequency of vigorous exercise and other risk indicators. During 105,141 person-years of follow-up, 285 new cases of NIDDM were reported. The age-adjusted incidence of NIDDM ranged from 369 cases per 100,000 person-years in men who engaged in vigorous exercise less than once weekly to 214 cases per 100,000 person-years in those exercising at least five times per week (P, trend, less than .001). Men who exercised at least once per week had an age-adjusted relative risk (RR) of NIDDM of 0.64 (95% Cl, 0.51 to 0.82; P = .0003) compared with those who exercised less frequently. The age-adjusted RR of NIDDM decreased with increasing frequency of exercise: 0.77 for once weekly, 0.62 for two to four times per week, and 0.58 for five or more times per week (P, trend, .0002). A significant reduction in risk of NIDDM persisted after adjustment for both age and body-mass index: RR, 0.71 (95% Cl, 0.56 to 0.91; P = .006) for at least once per week compared with less than once weekly, and P, trend, .009, for increasing frequency of exercise. Further control for smoking, hypertension, and other coronary risk factors did not materially alter these associations. The inverse relation of exercise to risk of NIDDM was particularly pronounced among overweight men. CONCLUSIONS: Exercise appears to reduce the development of NIDDM even after adjusting for body-mass index. Increased physical activity may be a promising approach to the primary prevention of NIDDM.

Adult↗
PubMed1992

Reproducibility and validity of an expanded self-administered semiquantitative food frequency questionnaire among male health professionals.

The authors assessed the reproducibility and validity of an expanded 131-item semiquantitative food frequency questionnaire used in a prospective study among 51,529 men. The form was administered by mail twice to a sample of 127 participants at a one-year interval. During this interval, men completed two one-week diet records spaced approximately 6 months apart. Mean values for intake of most nutrients assessed by the two methods were similar. Intraclass correlation coefficients for nutrient intakes assessed by questionnaires one year apart ranged from 0.47 for vitamin E without supplements to 0.80 for vitamin C with supplements. Correlation coefficients between the energy-adjusted nutrient intakes measured by diet records and the second questionnaire (which asked about diet during the year encompassing the diet records) ranged from 0.28 for iron without supplements to 0.86 for vitamin C with supplements (mean r = 0.59). These correlations were higher after adjusting for week-to-week variation in diet record intakes (mean r = 0.65). These data indicate that the expanded semiquantitative food frequency questionnaire is reproducible and provides a useful measure of intake for many nutrients over a one-year period.

Age Factors↗
PubMed1992

Comparison of measures of fatty acid intake by subcutaneous fat aspirate, food frequency questionnaire, and diet records in a free-living population of US men.

In 1986-1987, the authors assessed the fatty acid intake of 118 Boston-area men, aged 40-75 years, by a semiquantitative food frequency questionnaire administered twice, by two 7-day diet records, and by capillary gas chromatography of subcutaneous fat samples obtained by needle aspirate from the lateral buttock. Spearman correlation coefficients between diet record estimates of fatty acid intake (as a percentage of total fat) and fat aspirate measures (as a percentage of total peak area) were as follows: saturated fat, r = 0.16 (p = 0.09); monounsaturated fat, r = 0.22 (p = 0.01); and polyunsaturated fat, r = 0.49 (p = 0.0001). Spearman correlation coefficients between estimates derived from the food frequency questionnaire were as follows: saturated fat, r = 0.18 ( p = 0.05); monounsaturated fat, r = 0.14 (p = 0.14); polyunsaturated fat, r = 0.50 (p = 0.0001); and eicosapentaenoic acid, r = 0.47 (p = 0.0001). These data confirm that the polyunsaturated and eicosapentaenoic fatty acid content of subcutaneous fat is a measure of dietary intake of these fats. Although diet records are commonly thought to be the "gold standard" method of dietary assessment, the similar correlations observed between the fatty acid composition of adipose tissue and estimates of intake from the food frequency questionnaire and from diet records suggest that these two dietary assessment methods have similar validity in the measurement of polyunsaturated fatty acid intake.

Adipose Tissue↗
PubMed1992

Relationship of diet to risk of colorectal adenoma in men.

BACKGROUND: Rates of colorectal cancer in various countries are strongly correlated with per-capita consumption of red meat and animal fat and inversely associated with fiber consumption. There have been few studies, however, of dietary risk factors for colorectal adenomas, which are precursors of cancer. PURPOSE: Our purpose was to determine prospectively the relationship between dietary factors and risk of colorectal adenomas. METHODS: Using data from the Health Professionals Follow-up Study, we documented 170 cases of adenomas of the left colon or rectum in 7284 male health professionals who completed a food-frequency questionnaire in 1986 and who had a colonoscopy or sigmoidoscopy between 1986 and 1988. Relative risk (RR) of adenoma was determined according to quintiles of nutrient intakes. RESULTS: After adjustment for total energy intake, saturated fat was positively associated with risk of colorectal adenoma (P for trend = .006); RR for the highest versus the lowest quintile of intake was 2.0 (95% confidence interval [CI] = 1.2-3.2). Dietary fiber was inversely associated with risk of adenoma (P for trend less than .0001); RR for men in the highest versus the lowest quintile was 0.36 (95% CI = 0.22-0.60). All sources of fiber (vegetables, fruits, and grains) were associated with decreased risk of adenoma. For subjects on a high-saturated fat, low-fiber diet, the RR was 3.7 (95% CI = 1.5-8.8) compared with those on a low-saturated fat, high-fiber diet. The ratio of the intake of red meat to the intake of chicken and fish was positively associated with risk of adenoma (P for trend = .02). CONCLUSIONS: These prospective data provide evidence for the hypothesis that a diet high in saturated fat and low in fiber increases the risk of colorectal adenoma. They also support existing recommendations to substitute chicken and fish for red meat in the diet and to increase intake of vegetables, fruits, and grains to reduce risk of colorectal cancer.

Adult↗
PubMed1992

Type of postmenopausal hormone use and risk of breast cancer: 12-year follow-up from the Nurses' Health Study.

We prospectively examined the use of hormone replacement therapy in relation to breast cancer incidence in a cohort of women 30 to 55 years of age in 1976. During 12 years of follow-up (480,665 person-years) among postmenopausal women, 1,050 incident cases of breast cancer were documented. Overall, past users of replacement estrogen were not at increased risk. After adjustment for established risk factors, type of menopause, age at menopause, and current age, the rate ratio (RR) was 0.91, 95 percent confidence interval (CI) = 0.78-1.07. The risk of breast cancer was elevated significantly among current users (RR = 1.33, CI = 1.12-1.57); after adjusting for age, we observed no evidence of increasing risk with increasing duration of use among current users (P trend = 0.41), or among past users (P trend = 0.46). Women currently using unopposed estrogen (RR = 1.42, CI = 1.19-1.70), estrogen and progesterone (RR = 1.54, CI = 0.99-2.39), or progesterone alone (RR = 2.52, CI = 0.66-9.63), were all at increased risk of breast cancer compared with never users. These data suggest that long-term past use of estrogen replacement therapy is not related to risk, that current estrogen use increases risk of breast cancer to a modest degree, and that the addition of progesterone does not remove the increased risk observed with current use of unopposed estrogen.

Adult↗
PubMed1992

Carotenoids, retinol, and vitamin E and risk of proliferative benign breast disease and breast cancer.

We investigated the relationship between serum levels of retinol, beta-carotene, alpha-carotene, lycopene, alpha-tocopherol, and gamma-tocopherol as well as intakes of retinol, carotene, and vitamin E and the risks of breast cancer and proliferative benign breast disease (BBD) in a case-control study of postmenopausal women in the Boston, MA (United States) area. Serum nutrient data were available for 377 women with newly diagnosed stage I or II breast cancer and 173 women with proliferative BBD. Controls were 403 women who were evaluated at the same institutions but did not require a breast biopsy or whose biopsy revealed nonproliferative BBD. We observed no significant associations between serum levels of these micronutrients and risk of proliferative BBD or breast cancer. The risk of breast cancer was decreased among women in the highest quintile of intake of vitamin E from food sources only (odds ratio [OR] for the highest quintile = 0.4, 95 percent confidence interval [CI] = 0.2-0.9; P, trend across quintiles = 0.02) but less so for total vitamin E intake including supplements (OR = 0.7, CI = 0.4-1.3; P, trend = 0.07).

Aged↗
PubMed1992

Oral contraceptive use and the risk of type 2 (non-insulin-dependent) diabetes mellitus in a large prospective study of women.

We examined the association between oral contraceptive use and incidence of Type 2 (non-insulin-dependent) diabetes mellitus among 115117 female nurses free of diabetes, cardiovascular disease and cancer in 1976 and followed-up for 12 years. During 1237440 person years of follow-up, 2276 women who provided information on oral contraceptive use were clinically diagnosed with Type 2 diabetes. Women who used oral contraceptives in the past had only a slight and marginally increased relative risk of 1.10 (95% confidence interval 1.01, 1.21) compared to those women who had never used oral contraceptives after controlling for known risk factors of disease. We found no evidence of increased risk with longer duration of use or with shorter interval since last use. Current users did not have an increased risk of Type 2 diabetes (relative risk = 0.86, 95% confidence interval 0.46, 1.61) when compared to women who had never used the drug. There was no effect modification by obesity, family history of diabetes, or physical activity. These data suggest that past or current oral contraceptive use does not substantially influence subsequent risk of Type 2 diabetes.

Adult↗