Study on Folic acid suggests reduction of stroke risk for hypertensivesChris Middlebrooks (Author) Published Date : Mar 19, 2015 08:51 IST
A study on Folic acid combined with enalapril the medication for hypertension, involving over 20,000 adults having high blood pressure and no history of heart attack or stroke, and compared to enalapril alone showed significant reduction in the first stroke risk, according to a report in JAMA.
In China, stroke tops the list of causes leading to sudden death while it ranks second as a leading cause for death around the world. Some 77% of strokes around the world are first events and therefore primary prevention becomes particularly important. The efficacy of folic acid in primary prevention therapy remain uncertain because the data available is inconsistent and limited, as outlined in background information in the study report.
Dr.Yong Huo and colleagues of Peking University First Hospital in Beijing China were assigned 20,702 adults without a history of heart attack or stroke but with hypertension. They were then assigned randomly to receive a single pill combining folic acid 0.8 mg ; n=10,348 and enalapril 10 mg or a tablet with enalapril (10 mg; n-10,154) alone.
The trials were conducted in 32 communities from Anhui and Jiangsu provinces of China between 2008 May and 2013 August. Participants were also tested to ascertain variations in the MTHFR C677T gene (TT,CC, and CT genotypes) that could affect the levels of folate.
282 participants suffered first stroke during 4.5 years reckoned as median duration of treatment and this constituted 2.7% from the group treated with enalapril folic acid combination and that compared with 3.4% of 355 participants from the group treated with enalapril alone translating to 0.7% absolute reduction in risk and a 21% relative reduction in risk. Significant reductions were also noticed in the group treated with the enalapril folic acid combination with regard to ischemic stroke risk (2.2% compared to 2.8%) and composite cardiovascular events (stroke, heart attack and cardiovascular death) (3.1% against 3.9%).
With regard to heart attack, and hemorrhagic stroke risk, frequency of adverse events, or death from all causes, no significant differences were noticed between groups.
The authors of the study report state that this trial with data on MTHFR genotypes and the baseline folate levels in individuals has shown convincing evidence pointing to baseline folate levels as an important factor in determining the efficacy of folic acid in therapy for stroke prevention.
The CSPPT is the first large-scale randomized trial to test the hypothesis using individual measures of baseline folate levels. In this population without folic acid fortification, we observed considerable individual variation in plasma folate levels and clearly showed that the beneficial effect appeared to be more pronounced in participants with lower folate levels.
We speculate that even in countries with folic acid fortification and widespread use of folic acid supplements such as in the United States and Canada, there may still be room to further reduce stroke incidence using more targeted folic acid therapy in particular, among those with the TT genotype and low or moderate folate levels.
Study on Folic acid suggests reduction of stroke risk for hypertensives