The effect of folic acid in patients with cardiovascular disease: A systematic review and meta-analysis

BACKGROUND: The effectiveness of folic acid supplementation in stroke risk has been investigated, however, the available results are inconclusive and conflicting. The purpose of this systemic review and meta-analysis was to assess the effect of folic acid in patients with cardiovascular disease (CVD). METHODS: By searching the PubMed, EMBASE, and Cochrane library databases, we conducted a meta-analysis to evaluate effect of folic acid supplementation in patients with CVD. All-cause mortality, cardiovascular mortality, the risk of coronary heart disease (CHD) and stroke were summarized; hazard ratios (HR), the relative risk (RR) and its 95% confidence interval (CI) were also calculated. Fixed effects models were used to combine the data. A total of 12 randomized controlled trials, which involved 47,523 participants, met the inclusion criteria in this systematic review and meta-analysis. RESULTS: Our meta-analysis showed that cardiovascular patients who received folic acid therapy had significantly decreased risk of stroke (RR = 0.85, 95% CI = 0.77–0.94, P(heterogeneity) = .347, I(2) = 10.6%) compared with patients who received control treatment. However, no significant difference in all-cause mortality (HR, 0.97, 95% CI, 0.86–1.10, P(heterogeneity) = .315, I(2) = 15.4%), cardiovascular mortality (HR, 0.87, 95% CI, 0.66–1.15, P(heterogeneity) = .567, I(2) = 0) and risk of CHD (RR, 1.04, 95% CI, 0.99–1.10, P(heterogeneity) = .725, I(2) = 0) were found between the 2 groups. CONCLUSION: This meta-analysis suggested that folic acid supplementation significantly reduced the risk of stroke in patients with CVD.