Coronary heart disease mortality, plasma homocysteine, and B-vitamins: a prospective study

The results of prospective studies on the relations between the plasma concentration of total homocysteine (tHey) and B-vitamins, on the one hand, and coronary heart disease (CHD) mortality, on the other hand, are inconclusive and scarce considering the relation with B-vitamins. We prospectively determined these relations in a case-cohort study. The full-cohort existed in similar to 36,000 Dutch adults aged 20-59 years at baseline. The statistical analyses were done with a random sample from the cohort (n = 630) complemented with all subjects who died of CHD (n = 102) during a mean follow-up of 10.3 years. All subjects reported the absence of cardiovascular diseases (CVDs) at baseline. The plasma concentrations of tHey, folate, PLP, and vitamin B 12 were determined in samples obtained at baseline. Men with a tHey concentration in the highest tertile (T3) compared with men in the lowest tertile (T1) had a relative risk (RR) of 1.14 for CHD (95% confidence interval (CI): 0.50, 2.61) after adjusting for age, study center, hypertension, HDL and total cholesterol, smoking, and creatinine. For women, this RR was 2.04 (95%,, CI: 0.48, 8.62). For each 5 mumol/l increase in tHey, the RR of CHD was 1.03 (95% CI: 0.83-1.29) for men and women combined. In women only, high folate levels were associated with a statistically significant protection of fatal CHD T3 versus T1; RR: 0.22, 95% CI: 0.06, 0.87). Plasma PLP (136) and vitamin B12 concentrations were not associated with CHD risk. We conclude that elevated tHey concentrations do not seem to be a risk factor for CHD mortality in these relatively young healthy Dutch subjects free of baseline CVD. Higher folate concentrations may be protective of CHD, but this needs confirmation. (C) 2002 Published by Elsevier Science Ireland Ltd.