Effects of mixed dietary supplements on total plasma homocysteine concentrations (tHcy): a randomized, double-blind, placebo-controlled trial.

摘要

Although a number of studies have reported raised total plasma homocysteine (tHcy) concentrations in free-living older people, there are no data on homocysteine response to a mixed nutrient supplement in older patients. A raised plasma homocysteine concentration in older patients is partly a reflection of their co-morbidity, including impaired renal function, and there is uncertainty about the extent to which dietary interventions can improve plasma tHcy. To determine the plasma tHcy response to dietary supplements during acute illness. Two-hundred and thirty-six hospitalized, acutely ill older patients, who were part of a randomized double-blind placebo-controlled trial, were assigned to receive a daily oral nutritional supplement drink containing 1.3 mg of vitamin B2, 1.4 mg of vitamin B6, 1.5 μg of B12, 200 μg of folic acid, or a placebo, for 6 weeks. Outcome measures were plasma tHcy concentration at baseline, 6 weeks, and 6 months. The mean plasma tHcy concentration fell among patients given the supplements (mean difference 4.1 μmol/L [95 % C.I, 0.14 to 8.03), p = 0.043], but tHcy concentration increased between 6 weeks and 6 months, after patients stopped taking the supplements [mean difference -2.0 μmol/L (95 % C.I, -03.9 to -0.18), p = 0.033]. About 46 % of patients in the placebo group and 55 % of patients in the supplement group had hyperhomocysteinemia (>14 μmol/L) at baseline compared with 45 % and 29 % at the end of the treatment period. A mixed nutrient supplement containing physiological amounts of B vitamins significantly reduced plasma tHcy concentrations in older patients recovering from acute illness.