A micronutrient supplement modulates homocysteine levels regardless of vitamin B biostatus in elderly subjects

Abstract

Elevated homocysteine (Hcy) levels (15 ?mol/L) in the elderly are frequently associated with a higher risk of cardiovascular disease and cognitive decline. Several studies have already shown an Hcy-lowering effect of B vitamin supplementation in cohorts deficient in these nutrients. The aim of this randomized, double-blinded 12-week intervention study was to investigate whether Hcy levels in healthy elderly subjects (75.4 4.5 years, n=133) could be lowered with a micronutrient supplement (i.e., 400 ?g folic acid, 100 ?g cobalamin). Difference in mean initial Hcy levels between intervention (17.6 7.1 ?mol/L, n=65) and placebo group (18.9 6.1 ?mol/L, n=68) was not significant. The prevalence of cobalamin and folate deficiency in the total study population was low: 27% had serum-cobalamin levels 150 pmol/L, 12% holotranscobalamin (Holo-TC) levels 50 pmol/L, 13% low cobalamin status using the aggregated cobalamin marker 4cB12 and 10% red blood cell (RBC) folate 570 nmol/L. Nevertheless, the treated subjects still showed improved cobalamin and folate biostatus (serum cobalamin ?t12-t0: 63 48 pmol/L; Holo-TC ?t12-t0: 17 19 pmol/L; RBC folate ?t12-t0: 326 253 nmol/L) and Hcy levels (?t12-t0: 3.6 5.7 ?mol/L). The effects were statistically significant compared to the placebo group with p=0.005 (serum cobalamin), p=0.021 (Holo-TC), p=0.014 (RBC-folate) and 0.001 (Hcy). The Hcy-lowering effect was dependent on the initial Hcy levels (0.001). Our findings suggest that elevated Hcy levels in elderly subjects can be lowered regardless of the initial cobalamin and folate biostatus.