Effect of folic acid supplementation on risk of new-onset diabetes in adults with hypertension in China: Findings from the China Stroke Primary Prevention Trial (CSPPT)

Abstract

Background: The aim of the present post hoc analysis of the China Stroke Primary Prevention Trial (CSPPT) was to evaluate the effect of folic acid supplementation on the risk of new-onset diabetes in hypertensive adults in China.

Methods: In all, 20 702 hypertensive adults with no history of stroke and/or myocardial infarction (MI) were randomly assigned to receive double-blind daily treatment with tablets containing either: (i) 10 mg enalapril and 0.8 mg folic acid (n = 10 348); or (ii) 10 mg enalapril alone (n = 10 354). New-onset diabetes was defined as either self-reported physician-diagnosed diabetes or the use of glucose-lowering drugs during the follow-up period of the CSPPT.

Results: Over a median treatment duration of 4.5 years, new-onset diabetes occurred in 198 (2.0%) and 214 (2.1%) subjects in the enalapril-folic acid and enalapril groups, respectively (hazard ratio [HR] 0.92; 95% confidence interval [CI] 0.76-1.12). Similar results were observed when analyses were limited to subjects with baseline fasting glucose (FG) <7.0 mmol/L (HR 0.85; 95% CI 0.62-1.14). Furthermore, there was no significant group difference in: (i) the risk of new-onset FG ≥7.0 mmol/L (defined as FG <7.0 at baseline and ≥7.0 mmol/L at the last visit; relative risk [RR] 1.07; 95% CI 0.96-1.20); or (ii) the composite of new-onset diabetes or new-onset FG ≥7.0 mmol/L (RR = 1.06; 95% CI 0.95-1.19).

Conclusions: Among adults with hypertension with no history of stroke and/or MI in China, folic acid supplementation had no significant effect on the risk of new-onset diabetes.

Keywords: folic acid supplementation; hypertensive Chinese adults; new-onset diabetes; 中国成人高血压患者; 叶酸补充; 新发糖尿病.