Stroke is the second leading cause of death globally and the leading cause of death in China. Blood pressure is a well known contributing factor.
A new study published by JAMA included more than 20,000 Chinese adults with high blood pressure. The study determined that folic acid and the combined use of the hypertension medication enalapril and folic acid, compared with enalapril alone, significantly reduced the risk of first stroke.
The study consisted of assigning 20,702 adults with hypertension without history of stroke or heart attack randomly assigned to receive daily treatment with a single-pill combination containing enalapril (10 mg) and folic acid (0.8 mg; n = 10,348), or a tablet containing enalapril alone (10 mg; n = 10,354). The trial was conducted from May 2008 to August 2013 in 32 communities and participants were tested for the presence of a specific gene variant called MTHFR C677T gene (CC, CT, and TT genotypes) associated with folate levels.
The study findings revealed that the first stroke occurred in 282 participants (2.7 percent) in the enalapril-folic acid group compared with 355 participants (3.4 percent) in the enalapril group, representing an absolute risk reduction of 0.7 percent and a relative risk reduction of 21 percent. Statistical analysis also showed significant reductions among participants in the enalapril-folic acid group in the risk of ischemic stroke (2.2 percent vs 2.8 percent) and composite cardiovascular events (cardiovascular death, heart attack and stroke) (3.1 percent vs 3.9 percent).
The researchers attribute the beneficial effects witnessed in this study to folate levels where individuals with low folate levels and a specific genotype contributing to low folate levels could benefit from folate supplementation. Folic acid occurs naturally in food sources such as vegetables (especially dark green leafy vegetables), fruits and fruit juices, nuts, beans, and peas.
Yong Huo, Jianping Li, Xianhui Qin, Yining Huang, Xiaobin Wang, Rebecca F. Gottesman, Genfu Tang, Binyan Wang, Dafang Chen, Mingli He, Jia Fu, Yefeng Cai, Xiuli Shi, Yan Zhang, Yimin Cui, Ningling Sun, Xiaoying Li, Xiaoshu Cheng, Jian’an Wang, Xinchun Yang, Tianlun Yang, Chuanshi Xiao, Gang Zhao, Qiang Dong, Dingliang Zhu, Xian Wang, Junbo Ge, Lianyou Zhao, Dayi Hu, Lisheng Liu, Fan Fan Hou. Efficacy of Folic Acid Therapy in Primary Prevention of Stroke Among Adults With Hypertension in China. JAMA, 2015; DOI: 10.1001/jama.2015.2274