Biomedical subjects

Meir J Stampfer

Publications and source records attributed to Meir J Stampfer.

At least 109 records · Page 6Linked to original sources

PubMed2004

Coffee consumption and risk for type 2 diabetes mellitus.

BACKGROUND: In small, short-term studies, acute administration of caffeine decreases insulin sensitivity and impairs glucose tolerance. OBJECTIVE: To examine the long-term relationship between consumption of coffee and other caffeinated beverages and incidence of type 2 diabetes mellitus. DESIGN: Prospective cohort study. SETTING: The Nurses' Health Study and Health Professionals' Follow-up Study. PARTICIPANTS: The authors followed 41 934 men from 1986 to 1998 and 84 276 women from 1980 to 1998. These participants did not have diabetes, cancer, or cardiovascular disease at baseline. MEASUREMENTS: Coffee consumption was assessed every 2 to 4 years through validated questionnaires. RESULTS: The authors documented 1333 new cases of type 2 diabetes in men and 4085 new cases in women. The authors found an inverse association between coffee intake and type 2 diabetes after adjustment for age, body mass index, and other risk factors. The multivariate relative risks for diabetes according to regular coffee consumption categories (0, <1, 1 to 3, 4 to 5, or > or =6 cups per day) in men were 1.00, 0.98, 0.93, 0.71, and 0.46 (95% CI, 0.26 to 0.82; P = 0.007 for trend), respectively. The corresponding multivariate relative risks in women were 1.00, 1.16, 0.99, 0.70, and 0.71 (CI, 0.56 to 0.89; P < 0.001 for trend), respectively. For decaffeinated coffee, the multivariate relative risks comparing persons who drank 4 cups or more per day with nondrinkers were 0.74 (CI, 0.48 to 1.12) for men and 0.85 (CI, 0.61 to 1.17) for women. Total caffeine intake from coffee and other sources was associated with a statistically significantly lower risk for diabetes in both men and women. CONCLUSIONS: These data suggest that long-term coffee consumption is associated with a statistically significantly lower risk for type 2 diabetes.

Adult↗

PubMed2004

Predictors of 14-year changes in the total cholesterol to high-density lipoprotein cholesterol ratio in men.

BACKGROUND: Although the ratio of total to high-density lipoprotein cholesterol (TC/HDL) is a powerful predictor of cardiovascular disease (CVD), few studies have investigated which factors are associated with changes in this ratio over time. We examined predictors of a change in TC/HDL ratio over a period of 14 years among 4451 men free of CVD from the Physicians' Health Study. METHODS: Baseline and updated physician characteristics and CVD risk factors were included in multivariate linear and logistic regression models to determine factors associated with a change in the TC/HDL ratio or of having a ratio of > or =5 on follow-up. RESULTS: After a mean follow-up of 14 years, mean total cholesterol decreased by 7 mg/dL, HDL increased by 1 mg/dL, and the ratio decreased by 0.37. In multivariate logistic analyses, physicians were more likely to have a TC/HDL ratio of > or =5 at follow-up if they maintained a weight of > or =25 kg/m2 (OR, 1.69 [1.35-2.12]), gained weight (OR, 2.01 [1.55-2.62]), or became inactive (OR, 1.43 [1.11-1.83]). However, older physicians and those who consumed alcohol or received treatment for hyperlipidemia were more likely to have a ratio of <5. CONCLUSIONS: Although pharmacologic treatment for hyperlipidemia had the greatest favorable impact on the ratio over time, our data also show that maintaining an ideal weight and exercise have beneficial effects. We therefore advocate a renewed fervor for raising public awareness of the benefits of healthy lifestyle behaviors and pharmacologic treatments that are associated with long-term maintenance of favorable cholesterol levels.

Adult↗

PubMed2004

Associations of plasma homocysteine and the methylenetetrahydrofolate reductase C677T polymorphism with carotid intima media thickness among South Asian, Chinese and European Canadians.

BACKGROUND: Few studies have evaluated the associations of plasma homocysteine concentration, the methylenetetrahydrofolate reductase (MTHFR) C677T genotype and B vitamin concentration with intima media thickness (IMT) in multiethnic populations. METHODS: In the Study of Health Assessment and Risk in Ethnic groups (SHARE), we measured carotid IMT, fasting serum folate, serum B12, plasma pyridoxal-5'-phosphate (PLP) and plasma homocysteine and determined the MTHFR C677T genotype in a cross-sectional study of 818 South Asian, Chinese and European Canadians without previous history of CVD, cancer or diabetes during 1996-1998. RESULTS: Plasma homocysteine was inversely related to serum folate, serum B12, plasma PLP, B vitamin supplement use and Chinese ethnicity, and was positively associated with hypertension, smoking, IMT, MTHFR 677T/T genotype and South Asian ethnicity. Although ethnicity was not a statistically significant modifier, among carriers of the MTHFR 677T/T genotype with serum folate < or =14 nmol/L compared to >14 nmol/L, plasma homocysteine was significantly higher among South Asians (50.9% increase, P < 0.001) and Europeans (52.4% increase, P < 0.001) but not Chinese (11.0% increase, P > 0.05). Plasma homocysteine > 11.7 micromol/L was associated with a 5.9% (95% CI: 1.9%, 10.0%) increase in IMT (approximately 0.04 mm) in the pooled-data analyses with similar increases noted in the ethnic-specific analyses. The 677T/T genotype was not associated with a significant change in IMT in the pooled-data analyses (2.7%; 95% CI: -1.7%, 7.2%) nor in ethnic-specific analyses compared to other genotypes, although there were only 63 677T/T homozygotes. CONCLUSION: The combination of lower serum folate and the MTHFR 677T/T genotype is associated with increased plasma homocysteine among South Asians and Europeans, but the association is not evident among Chinese possibly because their serum folate may not have been low enough to compromise MTHFR activity. Plasma homocysteine > 11.7 micromol/L appears to be associated with a clinically important increase in IMT.

Asia, Southeastern↗

PubMed2004

A prospective study of the APOA1 XmnI and APOC3 SstI polymorphisms in the APOA1/C3/A4 gene cluster and risk of incident myocardial infarction in men.

BACKGROUND: Apolipoproteins AI/CIII/AIV play important roles in the metabolism of triglycerides (TG) and high-density lipoprotein (HDL) cholesterol. However, whether genetic variations in the APOA1/C3/A4 gene cluster are associated with the risk of myocardial infarction (MI) remains uncertain and prospective data are sparse. METHODS: In a prospective nested case-control study of 385 incident cases of MI and 373 age- and smoking-matched controls from the Physicians' Health Study, we examined the relationship between 2 common single nucleotide polymorphisms (APOA1 XmnI and APOC3 SstI) in the APOA1/C3/A4 gene cluster and haplotypes defined by these SNPs and risk of incident MI. RESULTS: No significant differences in allele or genotype frequency for the APOA1 XmnI and APOC3 SstI polymorphisms were detected between cases and controls. After adjusting for non-lipid coronary risk factors, the relative risks for incident MI were 1.00 (95% CI 0.68-1.47) for men carrying the X2 allele compared with those homozygous for the X1 allele in the APOA1 XmnI site and 1.07 (95% CI 0.69-1.64) for men carrying the S2 versus those homozygous for the S1 allele in the APOC3 SstI site. Moreover, we did not observe any effect modification by HDL or TG levels for the associations of these APOA1 and APOC3 genotypes with MI risk. There were significant differences in TG levels among men carrying different haplotypes (P=0.01) and men carrying the X1-S2 haplotype had higher levels of TG than those carrying the X2-S1 haplotype (202 mg/dl versus 157 mg/dl, P=0.03); however, haplotype frequencies defined by these two polymorphisms did not differ significantly between cases and controls. CONCLUSION: In this prospective study of apparently healthy middle-aged US men, carriers of the X1-S2 haplotype in the APOA1 XmnI and APOC3 SstI variants across the APOA1/C3/A4 gene cluster had higher TG levels, but there was no evidence for significant associations between these two common variants or haplotypes defined by them and risk of incident MI in this cohort.

Apolipoprotein A-I↗

PubMed2004

Homocysteine as a risk factor for coronary heart diseases and its association with inflammatory biomarkers, lipids and dietary factors.

The causal relation of total Homocysteine (tHcy) to coronary heart diseases (CHD) is unclear. In vitro studies suggest a proinflammatory effect. Among 32,826 women from the Nurses' Health Study who provided blood samples in 1989-1990, 237 CHD events were documented during 8 years of follow-up. The cases (1:2) were matched to controls on age, smoking, and month of blood draw. Plasma tHcy was inversely associated with blood levels of folate (partial r = -0.3, P < 0.0001) and B1(2) (r = -0.2, P < 0.0001) and with dietary intake of folate (r = -0.1, P < 0.01) and B(2) vitamin (r = -0.1, P = 0.01). tHcy was positively associated with soluble tumor necrosis receptor (sTNF-R) 1 and 2 (partial r = 0.2, P < 0.0001). In a multivariate model adjusted for age, smoking, BMI, parental history, hypertension, diabetes, postmenopausal hormone use, physical activity and alcohol intake, the relative risk of CHD between the extreme quartiles of tHcy was 1.66 (95% CI; 1.05-2.64, P trend = 0.02). The association was not appreciably attenuated after further adjustments for sTNF-R1, sTNF-R2, CRP, or Total Cholesterol:/HDL-c ratio. tHcy is an independent risk predictor of CHD and modestly associated with TNF-receptors. However, the inflammatory biomarkers measured could not explain its role in CHD.

C-Reactive Protein↗

PubMed2004

Magnesium intake and risk of coronary heart disease among men.

OBJECTIVE: Our aim in this study was to assess the relationship between magnesium intake and risk of coronary heart disease (CHD) among men. METHODS: A total of 39,633 men in the Health Professionals Follow-up Study who returned a dietary questionnaire in 1986 were followed up for 12 years. Intakes of magnesium, zinc and potassium and other nutrients were assessed in 1986, 1990 and 1994. Total CHD incidence (nonfatal myocardial infarction (MI) and fatal CHD) was ascertained by biennial questionnaire and mortality surveillance confirmed by medical record review. Standard CHD risk factors were recorded biennially. RESULTS: During 12 years of follow-up (414,285 person-years), we documented 1,449 cases of total CHD (1,021 non-fatal MI cases, and 428 fatal CHD). The age-adjusted relative risk (RR) of developing CHD in the highest quintile (median intake = 457 mg/day) compared with the lowest quintile (median intake = 269 mg/day) was 0.73 (95% CI 0.62-0.87, p for trend <0.0001). After controlling for standard CHD risk factors and dietary factors, the RR for developing CHD among men in the highest total magnesium intake quintile compared with those in the lowest was 0.82 (95% CI 0.65-1.05, p for trend = 0.08). For supplemental magnesium intake, the RR comparing the highest quintile to non-supplement users was 0.77 (95% CI 0.56-1.06, p for trend = 0.14). CONCLUSIONS: These results suggest that intake of magnesium may have a modest inverse association with risk of CHD among men.

Adult↗

PubMed2004

Dietary iron intake and blood donations in relation to risk of type 2 diabetes in men: a prospective cohort study.

BACKGROUND: Excessive iron stores may promote insulin resistance and lead to the development of type 2 diabetes. However, prospective data relating iron intake and blood donations (determinants of body iron stores) to diabetes incidence are limited. OBJECTIVE: We examined iron intake and blood donations in relation to the incidence of type 2 diabetes. DESIGN: We followed men aged 40-75 y who participated in the Health Professionals' Follow-up Study; were free of diabetes, cardiovascular disease, and cancer in 1986; and provided dietary data (n = 38 394). Of those participants, 33 541 also provided a history of blood donation during the past 30 y in 1992. RESULTS: During 12 y of follow-up, we ascertained 1168 new cases of type 2 diabetes. After adjustment for age, body mass index, and other diabetes risk factors, total iron intake was not associated with the risk of type 2 diabetes. Intakes of total heme iron [multivariate relative risk (RR) for extreme quintiles: 1.28; 95% CI: 1.02, 1.61; P for trend = 0.045] and of heme iron from red meat (RR: 1.63; 1.26, 2.10; P for trend < 0.001) were associated with an increased risk. However, heme-iron intake from sources other than red meat was not associated with diabetes risk (RR: 0.99; 0.81, 1.22). No significant associations were found between blood donation and the risk of type 2 diabetes. CONCLUSIONS: Heme-iron intake from red meat sources is positively associated with the risk of type 2 diabetes. Total iron intake, heme-iron intake from non-red meat sources, and blood donations are not related to the risk of type 2 diabetes.

Adult↗

PubMed2004

Diet and risk of ischemic heart disease in India.

BACKGROUND: Ischemic heart disease (IHD) is a leading cause of death in India. Dietary changes could reduce risk, but few studies have addressed the association between diet and IHD risk in India. OBJECTIVE: The goal was to address the association between diet and IHD risk among Indians in New Delhi (northern India) and Bangalore (southern India). DESIGN: We collected data from 350 cases of acute myocardial infarction and 700 controls matched on the basis of age, sex, and hospital as part of a hospital-based case-control study in 8 hospitals. Long-term dietary intake was assessed by using food-frequency questionnaires developed for New Delhi and Bangalore. We used conditional logistic regression to control for the matching factors and other predictors of risk. RESULTS: We observed a significant and dose-dependent inverse association between vegetable intake and IHD risk. The inverse association was stronger for green leafy vegetables; in multivariate analysis, persons consuming a median of 3.5 servings/wk had a 67% lower relative risk (RR: 0.33; 95% CI: 0.17, 0.64; P for trend = 0.0001) than did those consuming 0.5 servings/wk. Controlling for other dietary covariates did not alter the association. Cereal intake was also associated with a lower risk. Use of mustard oil, which is rich in alpha-linolenic acid, was associated with a lower risk than was use of sunflower oil [for use in cooking: RR: 0.49 (95% CI: 0.24, 0.99); for use in frying, RR: 0.29 (95% CI: 0.13, 0.64)]. CONCLUSION: Diets rich in vegetables and use of mustard oil could contribute to the lower risk of IHD among Indians.

Adult↗

PubMed2004

Dietary intake of n-3 and n-6 fatty acids and the risk of prostate cancer.

BACKGROUND: Laboratory studies have shown that n-3 fatty acids inhibit and n-6 fatty acids stimulate prostate tumor growth, but whether the dietary intake of these fatty acids affects prostate cancer risk in humans remains unclear. OBJECTIVE: We prospectively evaluated the association between intakes of alpha-linolenic (ALA; 18:3n-3), eicosapentaenoic (EPA; 20:5n-3), docosahexaenoic (DHA; 22:6n-3), linoleic (LA; 18:2n-6), and arachidonic (AA; 20:4n-6) acids and prostate cancer risk. DESIGN: A cohort of 47 866 US men aged 40-75 y with no cancer history in 1986 was followed for 14 y. RESULTS: During follow-up, 2965 new cases of total prostate cancer were ascertained, 448 of which were advanced prostate cancer. ALA intake was unrelated to the risk of total prostate cancer. In contrast, the multivariate relative risks (RRs) of advanced prostate cancer from comparisons of extreme quintiles of ALA from nonanimal sources and ALA from meat and dairy sources were 2.02 (95% CI: 1.35, 3.03) and 1.53 (0.88, 2.66), respectively. EPA and DHA intakes were related to lower prostate cancer risk. The multivariate RRs of total and advanced prostate cancer from comparisons of extreme quintiles of the combination of EPA and DHA were 0.89 (0.77, 1.04) and 0.74 (0.49, 1.08), respectively. LA and AA intakes were unrelated to the risk of prostate cancer. The multivariate RR of advanced prostate cancer from a comparison of extreme quintiles of the ratio of LA to ALA was 0.62 (0.45, 0.86). CONCLUSIONS: Increased dietary intakes of ALA may increase the risk of advanced prostate cancer. In contrast, EPA and DHA intakes may reduce the risk of total and advanced prostate cancer.

Adult↗

PubMed2004

Kidney dysfunction, inflammation, and coronary events: a prospective study.

Kidney dysfunction and high C-reactive protein (CRP) levels are independently associated with coronary events. However, it is unclear whether the risk of coronary events associated with decreased kidney function is at least partially mediated by inflammation and whether the association between inflammatory biomarkers and coronary events is influenced by level of kidney function. With the use of a prospective, nested, case-control study design, the association among kidney function, inflammatory biomarker levels, and coronary events was studied. A total of 244 women who were participants in the Nurses' Health Study and had no history of cardiovascular disease received a diagnosis of an incident coronary event (defined as nonfatal myocardial infarction or death as a result of coronary disease) during the follow-up period from 1990 to 1998 and were matched to 486 control subjects. Serum creatinine and inflammatory biomarker levels were measured in blood samples collected in 1989. Creatinine clearance (CrCl) was estimated using creatinine, age, weight, and height. In multivariate analyses, the odds ratio (OR) for a coronary event in women with an estimated CrCl <60 ml/min was 2.33 (95% confidence interval [CI], 1.01 to 5.38) compared with those with a CrCl > or =90 ml/min. When soluble tumor necrosis factor receptor (sTNFR) I and II levels were added into this model individually, the observed OR for women with CrCl <60 ml/min was attenuated. In analyses stratified by estimated CrCl, higher high-sensitivity CRP (hs-CRP), IL-6, and sTNFR I and II levels each were significantly associated with an increased odds of coronary events in women with an estimated CrCl < or =74 ml/min but not in women with an estimated CrCl > or =75 ml/min. The OR per 5-mg/L unit increase in hs-CRP was 1.68 (95% CI, 1.13 to 2.52) for women with an estimated CrCl < or =74 ml/min, compared with 1.23 (95% CI, 0.86 to 1.76) and 0.99 (95% CI, 0.76 to 1.29) for women with an estimated CrCl 75 to 89 and > or =90 ml/min, respectively (P = 0.004 for interaction). In conclusion, kidney dysfunction is associated with an increased odds of coronary events, and inflammation, as assessed by higher sTNFR I and II levels, may mediate some of this risk. Higher inflammatory biomarkers levels, specifically, hs-CRP, IL-6, and sTNFR I and II, were significantly associated with coronary events only in women with reduced kidney function. These findings warrant further investigation in other populations.

Adult↗

PubMed2004

Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up.

Diet plays an important role in the pathogenesis of kidney stones. Because the metabolism of many dietary factors, such as calcium, may change with age, the relation between diet and kidney stones may be different in older adults. Uncertainty also remains about the association between many dietary factors, such as vitamin C, magnesium, and animal protein, and the risk of kidney stone formation. To examine the association between dietary factors and the risk of incident, symptomatic kidney stones in men and to determine whether these associations vary with age, a prospective cohort study was conducted of 45,619 men without a history of nephrolithiasis. Self-administered food frequency questionnaires were used to assess diet every 4 yr. A total of 1473 incident symptomatic kidney stones were documented during 477,700 person-years of follow-up. For men aged <60 yr, the multivariate relative risk (RR) for stone formation in the highest quintile of dietary calcium as compared with the lowest quintile was 0.69 (95% confidence interval [CI], 0.56 to 0.87; P = 0.01 for trend). By contrast, there was no association between dietary calcium and stone formation in men aged 60 yr or older. The multivariate RR for men who consumed 1000 mg or greater of vitamin C per day compared with those who consumed less than the recommended dietary allowance of 90 mg/d was 1.41 (95% CI, 1.11 to 1.80; P = 0.01 for trend). Other dietary factors showed the following multivariate RR among men in the highest quintile of intake compared with those in the lowest: magnesium, 0.71 (95% CI, 0.56 to 0.89; P = 0.01 for trend); potassium, 0.54 (95% CI, 0.42 to 0.68; P < 0.001 for trend); and fluid, 0.71 (95% CI, 0.59 to 0.85; P < 0.001 for trend). Animal protein was associated with risk only in men with a body mass index <25 kg/m(2) (RR, 1.38; 95% CI, 1.05 to 1.81; P = 0.03 for trend). Sodium, phosphorus, sucrose, phytate, vitamin B(6), vitamin D, and supplemental calcium were not independently associated with risk. In conclusion, the association between calcium intake and kidney stone formation varies with age. Magnesium intake decreases and total vitamin C intake seems to increase the risk of symptomatic nephrolithiasis. Because age and body size affect the relation between diet and kidney stones, dietary recommendations for stone prevention should be tailored to the individual patient.

Adult↗

PubMed2004

Breastfeeding during infancy and the risk of cardiovascular disease in adulthood.

BACKGROUND: Numerous studies have reported associations between the type of feeding during infancy and subsequent cardiovascular risk factors. Only 2 studies have evaluated the relation between having been breastfed and the risk of adult cardiovascular events. METHODS: We examined this association among 87,252 female participants of the longitudinal Nurses' Health Study. Participants (all born between 1921 and 1946) reported in 1992 whether and for how long they were breastfed. During 8 years of follow up, there were 1099 cases of coronary heart disease and 940 strokes among women who knew whether they had been breastfed. We used proportional hazards models to estimate hazard ratios for cardiovascular events, adjusting for changing adult risk factors. RESULTS: Compared with women who were never breastfed, women who were breastfed had hazard ratios of 0.92 (95% confidence interval = 0.80-1.05) for coronary heart disease and 0.91 (0.79-1.06) for stroke, after adjustment for age, birthweight, and smoking. When body mass index was also included in the model, the results were similar. Looking within subgroups of stroke, hazard ratios were 0.86 (0.70-1.07) for ischemic stroke and 1.01 (0.70-1.46) for hemorrhagic stroke. Comparing women who were breastfed at least 9 months with those who were not breastfed, the hazard ratios were 0.84 (0.69-1.03) for coronary heart disease and 1.00 (0.81-1.23) for stroke. Breastfeeding history was not associated with high blood pressure in adulthood. CONCLUSIONS: These data suggest, but cannot establish, that breastfeeding in infancy may be associated with a small reduction in risk of ischemic cardiovascular disease in adulthood.

Adult↗

PubMed2004

Magnesium intake and risk of type 2 diabetes in men and women.

OBJECTIVE: To examine the association between magnesium intake and risk of type 2 diabetes. RESEARCH DESIGN AND METHODS: We followed 85,060 women and 42,872 men who had no history of diabetes, cardiovascular disease, or cancer at baseline. Magnesium intake was evaluated using a validated food frequency questionnaire every 2-4 years. After 18 years of follow-up in women and 12 years in men, we documented 4,085 and 1,333 incident cases of type 2 diabetes, respectively. RESULTS: After adjusting for age, BMI, physical activity, family history of diabetes, smoking, alcohol consumption, and history of hypertension and hypercholesterolemia at baseline, the relative risk (RR) of type 2 diabetes was 0.66 (95% CI 0.60-0.73; P for trend <0.001) in women and 0.67 (0.56-0.80; P for trend <0.001) in men, comparing the highest with the lowest quintile of total magnesium intake. The RRs remained significant after additional adjustment for dietary variables, including glycemic load, polyunsaturated fat, trans fat, cereal fiber, and processed meat in the multivariate models. The inverse association persisted in subgroup analyses according to BMI, physical activity, and family history of diabetes. CONCLUSIONS: Our findings suggest a significant inverse association between magnesium intake and diabetes risk. This study supports the dietary recommendation to increase consumption of major food sources of magnesium, such as whole grains, nuts, and green leafy vegetables.

Adult↗

PubMed2004

C-reactive protein and incident cardiovascular events among men with diabetes.

OBJECTIVE: Several large prospective studies have shown that baseline levels of C-reactive protein (CRP) are an independent predictor of cardiovascular events among apparently healthy individuals. However, prospective data on whether CRP predicts cardiovascular events in diabetic patients are limited so far. RESEARCH DESIGN AND METHODS: To investigate the association between plasma CRP levels and incidence of cardiovascular events among men with type 2 diabetes, we followed prospectively a cohort of 746 American men aged 46-81 years who were free of cardiovascular diseases at the time of blood collection in 1993-1994. RESULTS: During an average of 5 years of follow-up (3,986 person-years), we identified 103 incident cardiovascular events (18 myocardial infarction, 70 coronary artery bypass grafting or angioplasty, and 15 stroke), confirmed by medical records. After adjustment for age, BMI, smoking, alcohol consumption, physical activity, family history of coronary heart disease, history of high blood pressure, history of high serum cholesterol, aspirin use, and fasting status as well as for fibrinogen, creatinine, HbA(1c), and non-HDL cholesterol levels, CRP remained significantly associated with an increased risk of cardiovascular events. The relative risks for quartiles were 1.00, 1.51, 2.52, and 2.62 (95% CI: 1.29-5.32; P for trend: 0.011). We observed no effect modifications by plasma levels of LDL cholesterol, HDL cholesterol, non-HDL cholesterol, apolipoprotein B, HbA(1c), and fibrinogen or by BMI. CONCLUSIONS: High plasma levels of CRP were associated with an increased risk of incident cardiovascular events among diabetic men, independent of currently established lifestyle risk factors, blood lipids, and glycemic control.

Aged↗

PubMed2004

Non-HDL cholesterol and apolipoprotein B predict cardiovascular disease events among men with type 2 diabetes.

OBJECTIVE: To evaluate the role of non-HDL cholesterol and apolipoprotein (apo)B, markers of all potentially atherogenic lipoproteins, as predictors of cardiovascular disease (CVD) in comparison with LDL cholesterol in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: We prospectively followed 746 diabetic men in the Health Professionals' Follow-up Study who were aged 46-81 years and free of CVD or cancer at the time of blood draw in 1993-1994. During 6 years of follow-up, we ascertained 103 incident CVD cases. RESULTS: We used Cox proportional hazard modeling to estimate the relative risk (RR) of CVD. After adjustment for age, BMI, and other lifestyle risk factors, the multivariate RR of CVD (the highest versus the lowest quartile) was 2.34 (95% CI 1.26-4.32) for non-HDL cholesterol, 2.31 (1.23-4.35) for apoB, and 1.74 (0.99-3.06) for LDL cholesterol. Comparisons of nested models indicate that non-HDL cholesterol, but not apoB, adds significantly to the prediction of CVD risk beyond LDL cholesterol. The area under the receiver operating characteristic curve was 0.685, 0.691, 0.695, and 0.722 for the CVD risk-prediction model with LDL cholesterol, apoB, non-HDL cholesterol, and total cholesterol-to-HDL cholesterol ratio (or the non-HDL-to-HDL cholesterol ratio), respectively. CONCLUSIONS: Non-HDL cholesterol and apoB are more potent predictors of CVD incidence among diabetic men than LDL cholesterol. Statistically, the ratio of total to HDL cholesterol is the best predictor of CVD in this cohort of diabetic men.

Aged↗

PubMed2004

Lower toenail chromium in men with diabetes and cardiovascular disease compared with healthy men.

OBJECTIVE: Chromium may improve insulin sensitivity, which can modify the risk of diabetes and cardiovascular disease (CVD). Therefore, we evaluated the association between toenail chromium and CVD in diabetic men. RESEARCH DESIGN AND METHODS: We performed cross-sectional and nested case-control analyses among men aged 40-75 years within the Health Professionals Follow-up Study. The cross-sectional analysis compared men with diabetes only (n = 688), diabetes with prevalent CVD (n = 198), and healthy control subjects (n = 361). The nested case-control study included 202 men with baseline diabetes who developed incident CVD and 361 matched control subjects. RESULTS: Mean toenail chromium (microg/g) was 0.71 in healthy control subjects, 0.61 in diabetes-only subjects, and 0.52 in diabetic subjects with prevalent CVD (P for trend = 0.003). In the cross-sectional analysis, the multivariate odds ratio (OR) between extreme quartiles was 0.74 (95% CI 0.49-1.11; P for trend = 0.18), comparing diabetes only with healthy control subjects. A similar comparison between diabetic subjects with prevalent CVD and healthy control subjects yielded an OR of 0.45 (0.24-0.84; P for trend = 0.003). In the nested case-control study, comparing diabetic men with incident CVD with healthy control subjects, the multivariate OR was 0.65 (0.36-1.17; P for trend = 0.16) between extreme quartiles. When we combined prevalent and incident CVD cases among diabetic men and compared them with healthy control subjects, the OR was 0.62 (0.39-1.01; P for trend = 0.02) between extreme quartiles. CONCLUSIONS: Our results suggest that diabetic men with CVD have lower toenail chromium than healthy control subjects. However, this study could not distinguish between the effects of chromium on diabetes and those on CVD. Long-term clinical trials are needed to determine whether chromium supplementation is beneficial for preventing CVD among diabetic patients.

Adult↗

PubMed2004

Prostate-specific antigen and free prostate-specific antigen in the early detection of prostate cancer: do combination tests improve detection?

BACKGROUND: The combined use of free and total prostate-specific antigen (PSA) in early detection of prostate cancer has been controversial. This article systematically evaluates the discriminating capacity of a large number of combination tests. METHODS: Free and total PSA were analyzed in stored serum samples taken prior to diagnosis in 429 cases and 1,640 controls from the Physicians' Health Study. We used a classification algorithm called logic regression to search for clinically useful tests combining total and percent free PSA and receiver operating characteristic analysis and compared these tests with those based on total and complexed PSA. Data were divided into training and test subsets. For robustness, we considered 35 test-train splits of the original data and computed receiver operating characteristic curves for each test data set. RESULTS: The average area under the receiver operating characteristic curve across test data sets was 0.74 for total PSA and 0.76 for the combination tests. Combination tests with higher sensitivity and specificity than PSA > 4.0 ng/mL were identified 29 out of 35 times. All these tests extended the PSA reflex range to below 4.0 ng/mL. Receiver operating characteristic curve analysis indicated that the overall diagnostic performance as expressed by the area under the curve did not differ significantly for the different tests. CONCLUSIONS: Tests combining total and percent free PSA show modest overall improvements over total PSA. However, utilization of percent free PSA below a PSA threshold of 4 ng/mL could translate into a practically important reduction in unnecessary biopsies without sacrificing cancers detected.

Aged↗

PubMed2003

Folate, vitamin B6, and B12 intakes in relation to risk of stroke among men.

BACKGROUND AND PURPOSE: Folate, vitamin B6, and B12 deficiency are related to elevated blood homocysteine level. However, the effects of intakes of these vitamins on risk of stroke are still uncertain. This study examines intakes of folate, vitamin B6, and B12 in relation to risk of ischemic and hemorrhagic stroke. METHODS: We enrolled 43 732 men, aged 40 to 75 years, who were free of cardiovascular diseases and diabetes at baseline. Participants were followed from 1986 to 2000. Dietary information was assessed every 4 years using a detailed and validated semiquantitative food frequency questionnaire. The main outcome measures were incident ischemic and hemorrhagic strokes. RESULTS: A total of 725 incident strokes, including 455 ischemic, 125 hemorrhagic, and 145 unknown types of stroke, were documented during the 14-year follow-up. After adjustment for major lifestyle and dietary factors, intake of folate was associated with a significantly lower risk of ischemic but not hemorrhagic stroke. The multivariate relative risk of ischemic stroke was 0.71 (95% CI, 0.52 to 0.96; P for trend=0.05) for men in the highest quintile of intake compared with those who in the lowest quintile. Intake of vitamin B12, but not B6, was also inversely associated with risk of ischemic stroke. CONCLUSIONS: Our findings suggest that increased folate intake is associated with decreased risk of ischemic stroke in men.

Adult↗