Association of folate intake and serum homocysteine in elderly persons according to vitamin supplementation and alcohol use

Abstract

Background: The serum total homocysteine concentration (tHcy), an indicator of folate status and a possible risk factor for vascular disease, is elevated with impaired renal function and poor vitamin B-12 status, which are common in the elderly. Objective: Our objective was to determine the association between tHcy; folate intake, alcohol consumption, and other lifestyle factors in elderly persons. Design: This cross-sectional study used linear regression to model changes in tHcy. Subjects were 278 men and women aged 66-94 y studied in 1993. Results: Total folate intake was negatively associated with tHcy in models adjusted for age, sex, serum creatinine, and serum albumin. We found an interaction between food folate intake and supplement use. Food folate intake had an inverse dose-response relation with tHcy that was Limited to nonusers of supplements. Predicted tHcy was 1.5 mu mol/L lower in users of supplements containing folate and vitamin B-12 than in nonusers and was independent of food folate intake. We found a positive dose-response relation of coffee and tea intake with tHcy, a positive association for alcohol intake of greater than or equal to 60 drinks/mo compared with low intake, and an interaction of alcohol use with folate intake and supplement use. Compared with alcohol users, nonusers had higher predicted tHcy and a lower inverse dose-response relation of food folate intake with tHcy. Conclusions: The inverse association between folate intake and tHcy was strongest among nonusers of supplements and among alcohol drinkers. Identifying modifiable factors related to tHcy, a possible risk factor for vascular disease, is especially important in elderly persons.