Effect of folic acid treatment on carotid intima-media thickness of patients with coronary disease

Background Carotid intima-media thickness (CIMT) is a surrogate marker of cardiovascular morbility. Hyperhomocysteinemia, which is an independent cardiovascular risk factor, is associated with low folate levels. The aim of this study was to evaluate the effect of folic acid treatment on the evolution of CIMT in patients with coronary disease and homocysteinemia ≥ 9 μmol/l. Methods In 137 consecutive patients with coronary disease treated with statins and normal vitamin B12 values, a randomized treatment with open-label folic acid 2.5 mg/day (group A) or not (group B) was performed during 3 years. CIMT was evaluated by two-dimensional ultrasonography baseline and at the final of the study. Results Clinical, biochemical parameters and CIMT were similar in both groups of patients. Homocysteine levels decreased (12.4 ± 3.4 vs. 10.3 ± 2.4 μmol/l; p < 0.001) in group A, but not in group B. CIMT did not change neither in group A (0.71 ± 0.23 vs. 0.69 ± 0.20 mm; p = 0.34) nor in group B (0.74 ± 0.23 vs. 0.72 ± 0.29 mm; p = 0.39). In 12 patients of group A with methylenetetrahydrofolate reductase (MTHFR) 677TT mutation a decrease of CIMT was found (0.83 ± 0.35 vs. 0.72 ± 0.27 mm; p = 0.02), but a multiple linear regression only showed a trend to the association between CIMT changes and MTHFR 677TT (p = 0.051), probably due to the small number of patients with this mutation. Conclusions Long-time treatment with folic acid in patients with coronary disease and normal values of vitamin B12 decreases homocysteine levels. A CIMT decrease is observed in treated patients with MTHFR 677TT mutation.