Abstract
Purpose: High total plasma homocysteine (tHcy) is an independent risk factor for premature cardiovascular disease/mortality in the general population. tHcy has not been well defined as a risk factor in patients with diabetes mellitus (DM) and, therefore, we sought to investigate tHcy and its response to B-group vitamins in patients with DM. Design: Randomized placebo-controlled intervention study. Patients and Methods: Thirty patients with type II DM, aged 60±10 years (range 42-77 years) were compared with 17 age-matched (range 45-69 years) normoglycaemic subjects. Thereafter, the patients were randomly assigned to either B vitamin (B6, folic acid and B12) (n=18) or placebo (n=12) groups for 4 weeks. tHcy was measured using an amino acid analyzer. Results: Compared with the normoglycaemic patients, there were no differences in respect to tHcy, B12, plasma and erythrocyte (RBC) folate in patients with DM. In the B vitamin treatment group, plasma and RBC folate increased from 9.3±4.1 and 395±188 ng ml−1 to 15.3±3.8 and 665±248 ng ml−1 (p<0.001), respectively, whereas tHcy decreased from 10.7±3.8 μmol l−1 to 8.6±1.4 μmol l−1 (p<0.05). In the placebo group, no significant changes occurred in tHcy and B vitamin concentrations. Conclusions: Basal tHcy levels in patients with type II DM were not significantly different from the control group. This suggests that folic acid deficiency and marginal hyperhomocysteinaemia are no more problems among patients with DM than among the control group. tHcy levels fell among the treatment group after 1 month on 5 mg of folic acid together with other B vitamins which may prevent excess cardiovascular risk in patients with DM.