VITAMIN INTAKE - A POSSIBLE DETERMINANT OF PLASMA HOMOCYST(E)INE AMONG MIDDLE-AGED ADULTS

PURPOSE: Many epidemiologic studies have identified elevated plasma ho mocyst(e)ine as a risk factor for atherosclerosis and rhromboembolic d iseases. To examine the relationship between vitamin intakes and plasm a homocyst(e)ine, we analyzed dietary intake data from a case-control study of 322 middle-aged individuals with atherosclerosis in the carot id artery and 318 control subjects without evidence of this disease. M ETHODS: All of these individuals were selected from a probability samp le of 15,800 men and women who participated in the Atherosclerosis Ris k in Communities (ARIC) Study. RESULTS: Plasma homocyst(e)ine was inve rsely associated with intakes of folate, vitamin B6, and vitamin B12 ( controls only for this vitamin)-the three key vitamins in homocyst(e)i ne metabolism. Among nonusers of vitamin supplement products, on avera ge each tertile increase in intake of these vitamins was associated wi th 0.4 to 0.7 mu mol/L decrease in plasma homocyst(e)ine. An inverse a ssociation of plasma homocyst(e)ine was also found with thiamin, ribof lavin, calcium, phosphorus, and iron. Methionine and protein intake di d not show any significant association with plasma homocyst(e)ine. CON CLUSIONS: In almost all analyses, cases and controls showed similar as sociations between dietary variables and plasma homocyst(e)ine. Plasma homocyst(e)ine among users of vitamin supplement products was 1.5 mu mol/L lower than that among nonusers. Further studies to examine possi ble causal relationships among vitamin intake, plasma homocyst(e)ine, and cardiovascular disease are needed. (C) 1997 by Elsevier Science In c.