Serum folate and risk for coronary heart disease: Results from a cohort of US adults

PURPOSE: To assess the role of serum folate in the risk for coronary heart disease in a national cohort of US adults. METHODS: Data from the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study (N = 1921) were used to determine whether a low serum folate concentration was associated with an increased risk for incident coronary heart disease (N = 284). The Cox proportional hazards model adjusted for age, sex, race, education, serum cholesterol, systolic blood pressure, body mass index, cigarette smoking, and alcohol consumption. RESULTS: The association between folate and risk for coronary heart disease differed by age group (p = 0.03). Among persons aged 35-55 years, the relative risk for heart disease was 2.4 (95% confidence interval (CI), 1.1-5.2) for persons in the lowest quartile (less than or equal to 9.9 nmol/L) when compared with those in the highest quartile (greater than or equal to 21.8 nmol/L). However, among persons greater than or equal to 55 years the relative risk was 0.5 (95% CI, 0.3-0.8) for comparisons of the lowest versus highest quartiles. CONCLUSIONS: Ii the age differences in the risk for heart disease are confirmed, randomized clinical trials assessing the role of folic acid for the prevention of heart disease may need to include young adults in order to demonstrate benefits related to folate supplementation. (C) 1998 Elsevier Science Inc.