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Iso H, Rexrode K, Hennekens CH, Manson JE. Application of computer tomography-oriented criteria for stroke subtype classification in a prospective study. Ann Epidemiol 2000; 10:81-7. [PMID: 10691061 DOI: 10.1016/s1047-2797(99)00040-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE To apply stroke subclassification criteria based on computer tomography (CT) to strokes in the Nurses' Health Study and to assess reliability and validity of the criteria. METHODS Among 121,701 women aged 30-55 years at entry, subclassification criteria were applied to 1369 incident strokes which occurred from 1976 to 1994. Reproducibility of the subclassification criteria was assessed in a systematic sample of 100 strokes reviewed by two independent reviewers. As a validation, relative risks (RR) for stroke subtypes were examined in a prospective analysis of 112,282 women aged 34 to 59 years, free of cardiovascular disease and cancer in 1980, with follow-up through 1994. RESULTS Strokes were subclassified as follows: 226 subarachnoid hemorrhages, 135 intraparenchymal hemorrhages, 103 embolic, 217 large-artery occlusive, 309 lacunar, and 97 other thrombotic infarctions, as well as 282 strokes of undetermined type. No intercoder discrepancies were found in classification of subarachnoid hemorrhage, intraparenchymal hemorrhage, or embolic infarction, whereas there were four discrepancies relative to subclassification of thrombotic infarction, mostly due to inconsistent documentation of CT findings. In multivariate models, associations of older age (> 60 years), current smoking, history of diabetes, and high cholesterol with stroke subtypes were consistent with previous epidemiologic, clinical, or pathologic findings. CONCLUSIONS Stroke diagnostic criteria based primarily on CT were found to have a high rate of reliability and validity. These stroke subclassification criteria may be useful in examining whether associations for various lifestyle and health behaviors differ with stroke subtypes.
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Frieling UM, Schaumberg DA, Kupper TS, Muntwyler J, Hennekens CH. A randomized, 12-year primary-prevention trial of beta carotene supplementation for nonmelanoma skin cancer in the physician's health study. ARCHIVES OF DERMATOLOGY 2000; 136:179-84. [PMID: 10677093 DOI: 10.1001/archderm.136.2.179] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Although basic research provides plausible mechanisms for benefits of beta carotene supplementation on nonmelanoma skin cancer (NMSC) primarily consisting of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), observational studies are inconsistent. Randomized trial data are limited to 1 trial of secondary prevention that showed no effect of beta carotene on the incidence of NMSC after 5 years. OBJECTIVE To test whether supplementation with beta carotene reduces the risk for development of a first NMSC, including BCC and SCC. DESIGN Randomized, double-blind, placebo-controlled trial with 12 years of beta carotene supplementation and follow-up. SETTING Physicians' Health Study in the United States. PARTICIPANTS Apparently healthy male physicians aged 40 to 84 years in 1982 (N = 22 071). INTERVENTION Beta carotene, 50 mg, on alternate days. MAIN OUTCOME MEASURE Relative risk (RR) and 95% confidence interval (CI) for a first NMSC, BCC, and SCC. RESULTS After adjusting for age and randomized aspirin assignment, there was no effect of beta carotene on the incidence of a first NMSC (RR, 0.98; 95% CI, 0.92-1.05), BCC (RR, 0.99; 95% CI, 0.92-1.06), or SCC (RR, 0.97; 95% CI, 0.84-1.13). There was also no significant evidence of beneficial or harmful effects of beta carotene on NMSC by smoking status (current, past, or never). CONCLUSION This large-scale, randomized, primary prevention trial among apparently healthy well-nourished men indicates that an average of 12 years of supplementation with beta carotene does not affect the development of a first NMSC, including BCC and SCC.
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Hu FB, Willett WC, Manson JE, Colditz GA, Rimm EB, Speizer FE, Hennekens CH, Stampfer MJ. Snoring and risk of cardiovascular disease in women. J Am Coll Cardiol 2000; 35:308-13. [PMID: 10676674 DOI: 10.1016/s0735-1097(99)00540-9] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES To examine prospectively the association between snoring and incidence of cardiovascular disease (CVD) in women. BACKGROUND Whether snoring increases risk of CVD remains unclear; most previous studies have been small, not prospective and limited to men. METHODS Seventy-one thousand seven hundred seventy-nine female nurses 40 through 65 years of age and without previously diagnosed CVD or cancer at baseline in 1986 were followed up for eight years. Frequency of snoring was assessed using mailed questionnaires at baseline. RESULTS During eight years of follow-up, we documented 1,042 incident cases of major CVD events (644 coronary heart disease [CHD] and 398 stroke). Compared with nonsnorers, the age-adjusted relative risks (RRs) of CVD were 1.46 (95% confidence interval 1.23 to 1.74) for occasional snorers and 2.02 (1.62 to 2.53) for regular snorers. The age-adjusted RRs of CHD were 1.43 (1.15 to 1.77) for occasional snorers and 2.18 (1.65 to 2.87) for regular snorers. The age-adjusted RRs of stroke were 1.60 (1.21 to 2.12) and 1.88 (1.29 to 2.74), respectively. After further adjustment for smoking, body mass index (BMI) and other covariates, the positive association between snoring and CVD was attenuated but remained statistically significant (RRs of CVD were 1.20 [1.01 to 1.43] for occasional snorers and 1.33 [1.06-1.67] for regular snorers. CONCLUSIONS These data suggested that snoring is associated with a modest but significantly increased risk of CVD in women, independent of age, smoking, BMI and other cardiovascular risk factors. While further study is needed to elucidate the biological mechanism underlying this association, snoring may help clinicians identify individuals at higher risk for CVD.
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Christen WG, Gaziano JM, Hennekens CH. Design of Physicians' Health Study II--a randomized trial of beta-carotene, vitamins E and C, and multivitamins, in prevention of cancer, cardiovascular disease, and eye disease, and review of results of completed trials. Ann Epidemiol 2000; 10:125-34. [PMID: 10691066 DOI: 10.1016/s1047-2797(99)00042-3] [Citation(s) in RCA: 235] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE To assess the balance of benefits and risks of supplementation with beta-carotene, vitamin E, vitamin C, and multivitamins on cancer, cardiovascular (CVD), and eye diseases. DESIGN Physicians' Health Study II (PHS II) is a randomized, double-blind, placebo-controlled trial enrolling 15,000 willing and eligible physicians aged 55 years and older. PHS II will utilize a 2 x 2 x 2 x 2 factorial design to test alternate day beta-carotene, alternate day vitamin E, daily vitamin C, and a daily multivitamin, in the prevention of total and prostate cancer, CVD, and the age-related eye diseases, cataract and macular degeneration. PRIOR RESULTS: The final results of the recently completed Physicians' Health Study I (PHS I), a randomized, double-blind, placebo-controlled trial in 22,071 healthy US male physicians, indicated that beta-carotene supplementation (50 mg on alternate days) had no significant benefit or harm on cancer or CVD during more than 12 years of treatment and follow-up. In regards to cancer, there were possible benefits on total and prostate cancer in those with low baseline levels assigned to beta-carotene, a finding compatible with the Chinese Cancer Prevention Study for combined treatment with beta-carotene, vitamin E, and selenium in a poorly nourished population. Further, with respect to CVD, there were apparent benefits of beta-carotene supplementation on subsequent vascular events among a small subgroup of 333 men with prior angina or revascularization. The currently available data from randomized trials of primary prevention are sparse and inconsistent for vitamin E and non-existent for vitamin C and multivitamins. For eye diseases, namely cataract and age-related macular degeneration, there are no completed large-scale randomized trials of antioxidant vitamins. CONCLUSIONS PHS II is unique in several respects. PHS II is the only primary prevention trial in apparently healthy men testing the balance of benefits and risks of vitamin E on cancer and CVD. In addition, PHS II is the only primary prevention trial in apparently healthy men to test the balance of benefits and risks of vitamin C, multivitamins, as well as any single antioxidant vitamin, alone and in combination, on cancer, CVD, and eye diseases. Finally, PHS II is the only trial testing a priori the hypotheses that beta-carotene and vitamin E may reduce the risks of prostate cancer. Thus, PHS II will add unique as well as importantly relevant and complementary information to the totality of evidence from other completed and ongoing large-scale randomized trials on the balance of benefits and risks of beta-carotene, vitamin E, vitamin C, and multivitamins alone and in combination on prevention of cancer, CVD and eye diseases.
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Lotufo PA, Chae CU, Ajani UA, Hennekens CH, Manson JE. Male pattern baldness and coronary heart disease: the Physicians' Health Study. ARCHIVES OF INTERNAL MEDICINE 2000; 160:165-71. [PMID: 10647754 DOI: 10.1001/archinte.160.2.165] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To examine the association between male pattern baldness and the risk of coronary heart disease (CHD) events. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study among 22,071 US male physicians aged 40 to 84 years enrolled in the Physicians' Health Study. Of these, 19,112 were free of CHD at baseline and completed a questionnaire at the 11-year follow-up concerning their pattern of hair loss at age 45 years. Response options included no hair loss, frontal baldness only, or frontal baldness with mild, moderate, or severe vertex baldness. MAIN OUTCOME MEASURES Coronary heart disease events defined as nonfatal myocardial infarction (MI), angina pectoris, and/or coronary revascularization. RESULTS During 11 years of follow-up, we documented 1446 CHD events in this cohort. Compared with men with no hair loss, those with frontal baldness had an age-adjusted relative risk (RR) of CHD of 1.09 (95% confidence interval [CI], 0.94-1.25), while those with mild, moderate, or severe vertex baldness had RRs of 1.23 (95% CI, 1.05-1.43), 1.32 (95% CI, 1.10-1.59), and 1.36 (95% CI, 1.11-1.67), respectively (P for trend, <.001). Multivariate adjustment for age, parental history of MI, height, body mass index (weight in kilograms divided by the square of the height in meters as a continuous variable), smoking, history of hypertension, diabetes, high cholesterol level, physical activity, and alcohol intake did not materially alter these associations. Results were similar when nonfatal MI, angina, and coronary revascularization were examined separately, and when events were analyzed among men older and younger than 55 years at baseline. Vertex baldness was more strongly associated with CHD risk among men with hypertension (multivariate RR, 1.79; 95% CI, 1.31-2.44) or high cholesterol levels (multivariate RR, 2.78; 95% CI, 1.09-7.12). CONCLUSION Vertex pattern baldness appears to be a marker for increased risk of CHD events, especially among men with hypertension or high cholesterol levels.
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Gaziano JM, Gaziano TA, Glynn RJ, Sesso HD, Ajani UA, Stampfer MJ, Manson JE, Hennekens CH, Buring JE. Light-to-moderate alcohol consumption and mortality in the Physicians' Health Study enrollment cohort. J Am Coll Cardiol 2000; 35:96-105. [PMID: 10636266 DOI: 10.1016/s0735-1097(99)00531-8] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVES This study examined the relationship between light-to-moderate alcohol consumption and cause-specific mortality. BACKGROUND Previous studies suggest a J-shaped relation between alcohol and total mortality in men. A decrease in cardiovascular disease (CVD) mortality without a significant increase in other causes of mortality may explain the overall risk reduction at light-to-moderate levels. METHODS We conducted a prospective cohort study of 89,299 U.S. men from the Physicians' Health Study enrollment cohort who were 40 to 84 years old in 1982 and free of known myocardial infarction, stroke, cancer or liver disease at baseline. Usual alcohol consumption was estimated by a limited food frequency questionnaire. RESULTS There were 3,216 deaths over 5.5 years of follow-up. We observed a U-shaped relationship between alcohol consumption and total mortality. Compared with rarely/never drinkers, consumers of 1, 2 to 4 and 5 to 6 drinks per week and 1 drink per day had significant reductions in risk of death (multivariate relative risks [RRs] of 0.74, 0.77, 0.78 and 0.82, respectively) with no overall benefit or harm detected at the > or =2 drinks per day level (RR = 0.95; 95% confidence interval (CI), 0.79 to 1.14). The relationship with CVD mortality was inverse or L-shaped with apparent risk reductions even in the highest category of > or =2 drinks per day (RR = 0.76; 95% CI, 0.57 to 1.01). We found no clear harm or benefit for total or common site-specific cancers. For remaining other cancers, there was a nonsignificant 28% increased risk for those consuming > or =2 drinks per day. CONCLUSIONS These data support a U-shaped relation between alcohol and total mortality among light-to-moderate drinking men. The U-shaped curve may reflect an inverse association for CVD mortality, no association for common site-specific cancers and a possible positive association for less common cancers.
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Rexrode KM, Lee IM, Cook NR, Hennekens CH, Buring JE. Baseline characteristics of participants in the Women's Health Study. JOURNAL OF WOMEN'S HEALTH & GENDER-BASED MEDICINE 2000; 9:19-27. [PMID: 10718501 DOI: 10.1089/152460900318911] [Citation(s) in RCA: 227] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The Women's Health Study (WHS) is a randomized, double-blind, placebo-controlled trial designed to evaluate the balance of benefits and risks of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer in women. A total of 39,876 female health professionals, age 45 years or older and without a history of cardiovascular disease or cancer (other than nonmelanoma skin cancer), were randomized in a 2x2 factorial design to one of four treatment groups: active aspirin and vitamin E placebo, aspirin placebo and active vitamin E, both active agents, or both placebos. The process of randomization was successful, as evidenced by the equal distribution of a large number of baseline demographic, lifestyle, and health history characteristics among the four treatment groups. Similar distribution of known potential confounders, as well as the large sample size, provides reassuring evidence that unmeasured or unknown potential confounders are also equally distributed. As expected in a clinical trial, the women in the study are healthier in some respects than the general population, but they have very comparable rates of obesity, hypertension, and elevated cholesterol. With adequate duration of treatment and follow-up, this trial will provide important and relevant information on the balance of benefits and risks of aspirin and vitamin E supplementation in the primary prevention of cardiovascular disease and cancer in women.
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Gaziano JM, Hennekens CH, Satterfield S, Roy C, Sesso HD, Breslow JL, Buring JE. Clinical utility of lipid and lipoprotein levels during hospitalization for acute myocardial infarction. Vasc Med 1999; 4:227-31. [PMID: 10613626 DOI: 10.1177/1358836x9900400404] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The management of dyslipidemia after myocardial infarction (MI) is an important aspect of post-myocardial infarction care. However, acute changes in the lipid profile immediately following myocardial infarction have resulted in uncertainty regarding the clinical utility of lipid levels assessed during hospitalization for MI. We studied the effect of the timing of plasma lipid assessment among 294 patients who presented with MI to determine whether the differences between the serum lipid values in-hospital when compared with post-discharge values (generally 2-3 months after MI) would have a substantial impact on the decision to initiate lipid-lowering therapy. We found that the mean total and LDL cholesterol levels were significantly lower in-hospital when compared with generally 2-3 months later. However, patients whose lipids were measured within 48 h of presentation did not have significantly different values compared with generally 2-3 months post-discharge. Moreover, despite slightly lower in-hospital levels, 83.7% of patients were above the National Cholesterol Education Program target LDL for secondary prevention and 57.6% met the criteria for drug therapy based on in-hospital assessment. Total and LDL cholesterol levels fall modestly after an acute MI; however, from a clinical perspective, in-hospital levels can be used to guide decisions regarding lipid-lowering therapy which can begin in the immediate post-MI setting. In-hospital levels approximate post-MI levels, particularly if drawn within 48 h of presentation. All patients with acute myocardial infarction should have complete lipid profiles measured prior to discharge.
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Lee IM, Cook NR, Manson JE, Buring JE, Hennekens CH. Beta-carotene supplementation and incidence of cancer and cardiovascular disease: the Women's Health Study. J Natl Cancer Inst 1999; 91:2102-6. [PMID: 10601381 DOI: 10.1093/jnci/91.24.2102] [Citation(s) in RCA: 361] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND In observational studies, individuals with high intakes of fruits and vegetables containing beta-carotene experience lower risks of developing cancer. However, the few randomized trials of beta-carotene supplementation show no overall benefits; some even suggest harm. This trial was designed to test the effects of beta-carotene supplementation in women. METHODS The Women's Health Study is a randomized, double-blind, placebo-controlled trial originally testing aspirin, vitamin E, and beta-carotene in the prevention of cancer and cardiovascular disease among 39 876 women aged 45 years or older. The beta-carotene component was terminated early after a median treatment duration of 2.1 years (range = 0.00-2. 72 years). Statistical tests were two-sided. RESULTS Among women randomly assigned to receive beta-carotene (50 mg on alternate days; n = 19 939) or placebo (n =19 937), there were no statistically significant differences in incidence of cancer, cardiovascular disease, or total mortality after a median of 4.1 years (2.1 years' treatment plus another 2.0 years' follow-up). There were 378 cancers in the beta-carotene group and 369 cancers in the placebo group (relative risk [RR] = 1.03; 95% confidence interval [CI] = 0.89-1. 18). There were no statistically significant differences for any site-specific cancer or during years 1 and 2 combined and years 3 and up combined. For cardiovascular disease, there were no statistically significant differences for myocardial infarction (42 in the beta-carotene group versus 50 in the placebo group), stroke (61 versus 43), deaths from cardiovascular causes (14 versus 12), or the combined end point of these three events (116 versus 102; among women with more than one event, only the first was counted). Deaths from any cause were similar in the two groups (59 versus 55). Among smokers at baseline (13% of all women), there were no statistically significant differences in overall incidence of cancer (RR = 1.11; 95% CI = 0.78-1.58) or cardiovascular disease (RR = 1.01; 95% CI = 0. 62-1.63). CONCLUSION Among apparently healthy women, there was no benefit or harm from beta-carotene supplementation for a limited period on the incidence of cancer and of cardiovascular disease.
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Hu FB, Stampfer MJ, Manson JE, Ascherio A, Colditz GA, Speizer FE, Hennekens CH, Willett WC. Dietary saturated fats and their food sources in relation to the risk of coronary heart disease in women. Am J Clin Nutr 1999; 70:1001-8. [PMID: 10584044 DOI: 10.1093/ajcn/70.6.1001] [Citation(s) in RCA: 400] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
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.
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Febbo PG, Kantoff PW, Platz EA, Casey D, Batter S, Giovannucci E, Hennekens CH, Stampfer MJ. The V89L polymorphism in the 5alpha-reductase type 2 gene and risk of prostate cancer. Cancer Res 1999; 59:5878-81. [PMID: 10606227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
5alpha-Reductase type 2, the predominant prostatic isozyme of this protein, converts testosterone to dihydrotestosterone. It has been hypothesized that individuals with greater 5alpha-reductase activity are at increased risk for prostate cancer (CaP). A single nucleotide polymorphism of the 5alpha-reductase type 2 gene (SRD5A2) gives rise to a substitution of leucine (leu) for valine (val) at codon 89 (V89L), the presence of which may affect serum androstanediol glucuronide (AAG) levels. We studied the effect of this polymorphism on the risk of prostate cancer in a prospective, nested, case-control design within the Physicians' Health Study. In all controls (n = 799), the leu allele frequency was 0.30. Among the 386 controls with plasma AAG levels available, there was no significant association between AAG levels and V89L genotype. We also detected no significant association between risk for CaP and genotype [odds ratio: val/val = 1.0 (reference), leu/val = 0.96 (95% confidence interval, 0.76-1.20), and leu/ leu = 0.84 (95% confidence interval, 0.57-1.24)]. These data do not support a moderate to large effect of the SRD5A2 V89L polymorphism on plasma AAG levels or CaP risk in this predominantly Caucasian cohort, although a small effect cannot be completely excluded.
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Berger K, Ajani UA, Kase CS, Gaziano JM, Buring JE, Glynn RJ, Hennekens CH. Light-to-moderate alcohol consumption and the risk of stroke among U.S. male physicians. N Engl J Med 1999; 341:1557-64. [PMID: 10564684 DOI: 10.1056/nejm199911183412101] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Several studies have shown U- or J-shaped relations between alcohol consumption and the risk of stroke. We evaluated the effect of light-to-moderate alcohol intake on the risk of stroke, with separate analyses of ischemic stroke and hemorrhagic stroke. METHODS Our analyses were based on a prospective cohort study of 22,071 male physicians, 40 to 84 years old, who were participating in the Physicians' Health Study. At base line, the participants reported that they had no history of stroke, transient ischemic attack, or myocardial infarction and were free of cancer. Alcohol intake, reported by 21,870 participants at base line, ranged from none or almost none to two or more drinks per day. RESULTS During an average of 12.2 years of follow-up, 679 strokes were reported. As compared with participants who had less than one drink per week, those who drank more had a reduced overall risk of stroke (relative risk, 0.79; 95 percent confidence interval, 0.66 to 0.94) and a reduced risk of ischemic stroke (relative risk, 0.77; 95 percent confidence interval, 0.63 to 0.94). There was no statistically significant association between alcohol consumption and hemorrhagic stroke. The overall relative risks of stroke for the men who had one drink per week, two to four drinks per week, five or six drinks per week, or one or more drinks per day were 0.78 (95 percent confidence interval, 0.59 to 1.04), 0.75 (95 percent confidence interval, 0.58 to 0.96), 0.83 (95 percent confidence interval, 0.62 to 1.11), and 0.80 (95 percent confidence interval, 0.64 to 0.99), respectively, in an analysis in which we controlled for major risk factors for stroke. CONCLUSIONS Light-to-moderate alcohol consumption reduced the overall risk of stroke and the risk of ischemic stroke in men. The benefit is apparent with as little as one drink per week. Greater consumption, up to one drink per day, does not increase the observed benefit.
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Rohde LE, Hennekens CH, Ridker PM. Survey of C-reactive protein and cardiovascular risk factors in apparently healthy men. Am J Cardiol 1999; 84:1018-22. [PMID: 10569656 DOI: 10.1016/s0002-9149(99)00491-9] [Citation(s) in RCA: 241] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Several prospective studies have demonstrated a direct association between C-reactive protein (CRP) levels and the risks of developing cardiovascular disease. Few studies, however, have explored the interrelations between CRP levels and other risk factors for cardiovascular disease. We evaluated the relation of CRP with several cardiovascular risk factors in a cross-sectional survey of 1,172 apparently healthy men. There were significant positive associations between CRP levels and age, number of cigarettes smoked per day, body mass index, systolic and diastolic blood pressure, total cholesterol, triglycerides, lipoprotein(a), apolipoprotein B, tissue-type plasminogen activator antigen, D-dimers, total homocysteine, and fibrinogen (all p values <0.05). Significant inverse associations were observed for exercise frequency, high-density lipoprotein cholesterol, and apolipoprotein A-I and A-II (all p values <0.02). In multivariate analysis, age, smoking status, and serum levels of tissue-type plasminogen activator antigen, fibrinogen, lipoprotein(a), and total homocysteine were independent correlates of CRP levels. Finally, in an analysis controlled either for all the independent correlates or for several usual risk factors, we observed progressive increases in levels of CRP with increasing prevalence of risk factors (p for trend <0.001 for independent correlates and <0.01 for usual risk factors). In conclusion, in a large cohort of apparently healthy men, CRP levels were associated with several cardiovascular risk factors. These data are compatible with the hypothesis that CRP levels may be a marker for preclinical cardiovascular disease.
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Cook NR, Stampfer MJ, Ma J, Manson JE, Sacks FM, Buring JE, Hennekens CH. Beta-carotene supplementation for patients with low baseline levels and decreased risks of total and prostate carcinoma. Cancer 1999; 86:1783-92. [PMID: 10547552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND The Physicians' Health Study was a randomized, double-blind, placebo-controlled trial using a 2x2 factorial design including supplementation with beta-carotene (50 mg every other day) in the primary prevention of cancer among 22,071 U.S. male physicians ages 40-84 years at randomization. Before randomization, the authors collected baseline blood specimens to determine whether any benefit was greater among or confined to those with low baseline levels of beta-carotene. METHODS Baseline blood samples were collected from 14,916 participants. These samples were assayed, according to a nested case-control design, from 1439 men subsequently diagnosed with cancer over 12 years of follow-up (631 with prostate carcinoma) and 2204 controls matched by age and smoking habits. RESULTS Men in the lowest quartile for plasma beta-carotene at baseline had a marginally significant (P = 0.07) increased risk of cancer compared with those in the highest quartile (relative risk [RR] = 1.30, 95% confidence interval [CI], 0.98-1.74). Men in the lowest quartile assigned at random to beta-carotene supplementation had a possible but nonsignificant decrease in overall cancer risk (RR = 0.83, 95% CI, 0.63-1.09) compared with those assigned to placebo. This was primarily due to a significant reduction in the risk of prostate carcinoma (RR = 0.68, 95% CI, 0. 46-0.99) in this group. After the first 2 years of follow-up were excluded, the results were virtually unchanged. CONCLUSIONS These prespecified subgroup analyses appeared to support the idea that beta-carotene supplementation may reduce risk of prostate carcinoma among those with low baseline levels. Further follow-up of this population will help determine whether these findings are valid.
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Rubattu S, Ridker P, Stampfer MJ, Volpe M, Hennekens CH, Lindpaintner K. The gene encoding atrial natriuretic peptide and the risk of human stroke. Circulation 1999; 100:1722-6. [PMID: 10525492 DOI: 10.1161/01.cir.100.16.1722] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Recent evidence from an animal model of stroke, the stroke-prone spontaneously hypertensive rat, implicated the gene encoding atrial natriuretic peptide (ANP) as a possible candidate contributing to the likelihood of experiencing a stroke. The purpose of the present study was to investigate the role of ANP in the pathogenesis of cerebrovascular accidents in humans. METHODS AND RESULTS We investigated 2 previously known markers at ANP, G1837A and T2238C, for their possible association with the occurrence of stroke. This was the largest matched case-controlled sample studied thus far; the sample was drawn from a large prospective study (the Physician's Health Study). When assuming a dominant mode of inheritance, a statistically significant positive association was observed for the 1837A allele, indicating an odds ratio of 1.64 (95% confidence interval, 1.01 to 2.65) for stroke. This observation led to the discovery of a new molecular variant in exon 1, G664A, which was responsible for a valine-to-methionine substitution in the proANP peptide. This mutation, which was in linkage disequilibrium with the G1837A marker, was associated with the occurrence of stroke (odds ratio, 2.0; 95% confidence interval, 1.17 to 3.19; P=0.01). CONCLUSIONS Our findings suggest that molecular variants of the ANP gene may represent an independent risk factor for cerebrovascular accidents in humans. The strong parallelism to the experimental data obtained in the stroke-prone animal model provides assurance for the relevance of our observation.
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Ridker PM, Hennekens CH, Buring JE, Kundsin R, Shih J. Baseline IgG antibody titers to Chlamydia pneumoniae, Helicobacter pylori, herpes simplex virus, and cytomegalovirus and the risk for cardiovascular disease in women. Ann Intern Med 1999; 131:573-7. [PMID: 10523217 DOI: 10.7326/0003-4819-131-8-199910190-00004] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Results of cross-sectional and retrospective studies have suggested that chronic infection may be a risk factor for cardiovascular disease. However, prospective data evaluating the relation between baseline antibody titers against various plausible agents and risk for cardiovascular disease are sparse, particularly among women. OBJECTIVE To determine whether previous exposure to Chlamydia pneumoniae, Helicobacter pylori, herpes simplex virus, or cytomegalovirus is associated with increased risk for cardiovascular events. DESIGN Prospective, nested, case-control study. SETTING Women's Health Study. PARTICIPANTS Apparently healthy postmenopausal women. MEASUREMENTS IgG antibody titers against C. pneumoniae, H. pylori, herpes simplex virus, and cytomegalovirus were measured in baseline blood samples obtained from 122 study participants who subsequently reported a first cardiovascular event (case-patients) and 244 participants matched for age and smoking status who did not report a cardiovascular event (controls) during 3 years of follow-up. RESULTS Little evidence was found of an association between risk for cardiovascular events and baseline IgG seropositivity for antibodies against C. pneumoniae (rate ratio, 1.1 [95% CI, 0.7 to 1.8]), H. pylori (rate ratio, 0.90 [CI, 0.6 to 1.4]), herpes simplex virus (rate ratio, 1.2 [CI, 0.6 to 2.1]), and cytomegalovirus (rate ratio, 0.9 [CI, 0.6 to 1.5]). In addition, there was little evidence of an association between a participant's total number of infections and subsequent cardiovascular risk (P > 0.2). CONCLUSION In apparently healthy postmenopausal women, little evidence was found that previous infection, as measured by IgG antibody titers to C. pneumoniae, H. pylori, herpes simplex virus, and cytomegalovirus, is associated with subsequent risk for cardiovascular disease.
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Hu FB, Willett WC, Colditz GA, Ascherio A, Speizer FE, Rosner B, Hennekens CH, Stampfer MJ. Prospective study of snoring and risk of hypertension in women. Am J Epidemiol 1999; 150:806-16. [PMID: 10522651 DOI: 10.1093/oxfordjournals.aje.a010085] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Whether snoring increases the risk of hypertension remains unclear. The authors examined the association between snoring and risk of hypertension in a cohort of 73,231 US female nurses aged 40-65 years and without diagnosed cardiovascular disease or cancer in 1986. Blood pressure levels and physician-diagnosed hypertension were self-reported through validated questionnaires. During 8 years of follow-up, 7,622 incident cases of physician-diagnosed hypertension were reported. Older age, smoking, body mass index, waist circumference, waist-hip ratio, weight gain, less physical activity, and sleeping on the back were directly associated with regular snoring. After adjustment for age, body mass index, waist circumference, and other covariates, snoring was associated with a significantly higher prevalence of hypertension at baseline (odds ratio = 1.22, 95% confidence interval (CI): 1.16, 1.27 for occasional snoring and odds ratio = 1.43, 95% CI: 1.33, 1.5 for regular snoring). In prospective analyses using incident cases of hypertension as the outcome, the multivariate relative risks of hypertension were 1.29 (95% CI: 1.22, 1.37) for occasional snoring and 1.55 (95% CI: 1.42, 1.70) for regular snoring. In addition, snoring was associated with significantly higher systolic and diastolic blood pressure levels. These data suggest that snoring may increase risk of hypertension in women, independent of age, body mass index, waist circumference, and other lifestyle factors.
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Joshipura KJ, Ascherio A, Manson JE, Stampfer MJ, Rimm EB, Speizer FE, Hennekens CH, Spiegelman D, Willett WC. Fruit and vegetable intake in relation to risk of ischemic stroke. JAMA 1999; 282:1233-9. [PMID: 10517425 DOI: 10.1001/jama.282.13.1233] [Citation(s) in RCA: 632] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONTEXT Few studies have evaluated the relationship between fruit and vegetable intake and cardiovascular disease. OBJECTIVE To examine the associations between fruit and vegetable intake and ischemic stroke. DESIGN, SETTING, AND SUBJECTS Prospective cohort studies, including 75 596 women aged 34 to 59 years in the Nurses' Health Study with 14 years of follow-up (1980-1994), and 38683 men aged 40 to 75 years in the Health Professionals' Follow-up Study with 8 years of follow-up (1986-1994). All individuals were free of cardiovascular disease, cancer, and diabetes at baseline. MAIN OUTCOME MEASURE Incidence of ischemic stroke by quintile of fruit and vegetable intake. RESULTS A total of 366 women and 204 men had an ischemic stroke. After controlling for standard cardiovascular risk factors, persons in the highest quintile of fruit and vegetable intake (median of 5.1 servings per day among men and 5.8 servings per day among women) had a relative risk (RR) of 0.69 (95% confidence interval [CI], 0.52-0.92) compared with those in the lowest quintile. An increment of 1 serving per day of fruits or vegetables was associated with a 6% lower risk of ischemic stroke (RR, 0.94; 95 % CI, 0.90-0.99; P =.01, test for trend). Cruciferous vegetables (RR, 0.68 for an increment of 1 serving per day; 95% CI, 0.49-0.94), green leafy vegetables (RR, 0.79; 95% CI, 0.62-0.99), citrus fruit including juice (RR, 0.81; 95% CI, 0.68-0.96), and citrus fruit juice (RR, 0.75; 95% CI, 0.61-0.93) contributed most to the apparent protective effect of total fruits and vegetables. Legumes or potatoes were not associated with lower ischemic stroke risk. The multivariate pooled RR for total stroke was 0.96 (95% CI, 0.93-1.00) for each increment of 2 servings per day. CONCLUSIONS These data support a protective relationship between consumption of fruit and vegetables-particularly cruciferous and green leafy vegetables and citrus fruit and juice-and ischemic stroke risk.
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Gaziano JM, Sesso HD, Breslow JL, Hennekens CH, Buring JE. Relation between systemic hypertension and blood lipids on the risk of myocardial infarction. Am J Cardiol 1999; 84:768-73. [PMID: 10513771 DOI: 10.1016/s0002-9149(99)00435-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We sought to evaluate the potential interactions between systemic hypertension and blood lipids on the risk of myocardial infarction (MI). Recent evidence suggests that hypertension may interact with other risk factors such as dyslipidemia in the development of coronary heart disease. However, the precise nature of that interrelation remains unclear. We selected 340 cases of first MI and an equal number of age-, sex-, and community-matched controls. Data were collected on a large number of coronary risk factors, and fasting blood samples were obtained. Logistic regression was used to calculate the odds ratio (OR) of nonfatal MI. The age- and sex-adjusted OR of MI was 1.61 (95% confidence interval [CI] 1.15 to 2.25) among treated hypertensives compared with nonhypertensives. Further adjustment for coronary risk factors did not materially alter the results (OR 1.67, 95% CI 1.16 to 2.41). To explore the interrelations among hypertension, lipids, and risk of MI, each lipoprotein parameter was individually added to the risk factor-adjusted multivariate model. The apparent risk associated with hypertension was substantially attenuated by the addition of either high-density lipoprotein cholesterol (OR 1.25, 95% CI 0.82 to 1.90) or triglycerides (OR 1.37, 95% CI 0.91 to 2.05). No significant interactions were found between hypertension and any lipoprotein parameter. These data indicate that the risk of MI associated with treated hypertension may have a lipid mechanism involving high-density lipoprotein cholesterol and/or triglycerides.
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Karlson EW, Lee IM, Cook NR, Manson JE, Buring JE, Hennekens CH. Comparison of self-reported diagnosis of connective tissue disease with medical records in female health professionals: the Women's Health Cohort Study. Am J Epidemiol 1999; 150:652-60. [PMID: 10490005 DOI: 10.1093/oxfordjournals.aje.a010064] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
To compare self-report of connective tissue disease (CTD) with medical records, subjects were selected from 395,543 female health professionals with and without breast implants who reported CTD on mailed questionnaires from 1992 to 1995. The authors identified 220 women with breast implants (exposed) who self-reported CTD and a random sample of 879 women without breast implants (unexposed) who also self-reported CTD, matched by age and date of diagnosis. Medical records were reviewed using classification criteria from the American College of Rheumatology or other published criteria. After up to three requests and a telephone call, 27.7% of the women provided consent for medical record review. Exposed women appeared somewhat more likely (33.2% vs. 26.3%, p = 0.04) to provide consent. Using medical record reviews for 90% of the women who provided consent, confirmation rates of definite CTD were similar among the exposed and unexposed (22.7% vs. 24.0%, p = 0.83). This study demonstrates the difficulty of obtaining consent for medical record review of CTD reported to have occurred years ago in women with and without breast implants. Confirmation rates were low but were similar in exposed and unexposed. Despite the fact that the study had low participation rates, the data suggest that relative risk estimates for any definite CTD among women with breast implants compared with women without breast implants would be similar in analyses of self-reported or medical record-confirmed cases.
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Iso H, Stampfer MJ, Manson JE, Rexrode K, Hennekens CH, Colditz GA, Speizer FE, Willett WC. Prospective study of calcium, potassium, and magnesium intake and risk of stroke in women. Stroke 1999; 30:1772-9. [PMID: 10471422 DOI: 10.1161/01.str.30.9.1772] [Citation(s) in RCA: 210] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
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.
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Liu S, Stampfer MJ, Hu FB, Giovannucci E, Rimm E, Manson JE, Hennekens CH, Willett WC. Whole-grain consumption and risk of coronary heart disease: results from the Nurses' Health Study. Am J Clin Nutr 1999; 70:412-9. [PMID: 10479204 DOI: 10.1093/ajcn/70.3.412] [Citation(s) in RCA: 427] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
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.
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Ma J, Stampfer MJ, Christensen B, Giovannucci E, Hunter DJ, Chen J, Willett WC, Selhub J, Hennekens CH, Gravel R, Rozen R. A polymorphism of the methionine synthase gene: association with plasma folate, vitamin B12, homocyst(e)ine, and colorectal cancer risk. Cancer Epidemiol Biomarkers Prev 1999; 8:825-9. [PMID: 10498402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
We previously reported (J. Chen et al., Cancer Res., 56: 4862-4864, 1996; J. Ma et al., Cancer Res., 57: 1098-1102, 1997) that a 5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphism (677C-->T, ala-->val) was associated with lower risk of colorectal cancer. In this study, we examined the relationship of a polymorphism (2756A-->G, asp-->gly) in the gene (MTR) for methionine synthase, another important enzyme in the same folate/methionine/homocyst(e)ine metabolic pathway, with risk of colorectal cancer among 356 cases and 476 cancer-free controls. The frequency of the homozygous variant genotype (gly/gly) was slightly lower among cases (3%) than controls (5%). The odds ratio for the gly/gly genotype was 0.59 [95% confidence interval (CI), 0.27-1.27] compared with those with the homozygous wild type (asp/asp). There were no significant differences in plasma levels of folate, vitamin B12, and homocyst(e)ine (tHcy) among the MTR genotypes, in contrast to the MTHFR polymorphism. However, similar to the interaction observed for the MTHFR polymorphism among men who consumed less than 1 alcoholic drink/day, those with the gly/gly genotype had a lower risk of colorectal cancer with an odds ratio of 0.27 (95% CI, 0.09-0.81) compared with those with the asp/asp genotype. The possible association of the MTR polymorphism with lower risk of colorectal cancer especially among those with low alcohol consumption, in the same direction as for the MTHFR polymorphism, is intriguing. However, our study had limited statistical power because of the low frequency of the MTR variant genotype, which is reflected in the wide CIs. Hence, these findings need to be confirmed in larger populations.
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Iso H, Hennekens CH, Stampfer MJ, Rexrode KM, Colditz GA, Speizer FE, Willett WC, Manson JE. Prospective study of aspirin use and risk of stroke in women. Stroke 1999; 30:1764-71. [PMID: 10471421 DOI: 10.1161/01.str.30.9.1764] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
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.
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