Effect of valsartan on insulin resistance in patients with hypertension: a systematic review and meta-analysis

Objective: The aim of the present meta-analysis was to evaluate the effect of valsartan on insulin resistance in patients with hypertension. Methods: We searched the electronic databases, including PubMed, EMBASE and The Chorance Library, for randomized controlled trials (RCTs) comparing the effect of valsartan and the other antihypertensive drugs on insulin resistance in patients with hypertension. We carried out statistical analyses using RevMan version 5.3 and used the Cochrane bias risk evaluation tools to assess the risk of bias. Results: A total of eight studies involving 935 subjects were included in the present meta-analysis. The results showed that compared with other antihypertensive drugs, valsartan possessed a slight but non-significant trend to reduce the level of HOMA-IR [WMD=-0.42; 95% confidence interval (CI) -0.84, -0.01 (P=0.05)], glycated hemoglobin [WMD=-0.06; 95% CI: -0.27, 0.14; (P=0.55)] and fasting plasma glucose [WMD=-0.11; 95% CI: -0.27, 0.05; (P=0.18)]. However, valsartan was found to be more effective at reducing the insulin level [WMD=-1.15; 95% CI -2.00, -0.31]. In addition, systolic blood pressure [WMD=-4.09; 95% CI: -8.83, 0.66], but not diastolic blood pressure [WMD=-2.41; 95% CI: -3.53, -1.30], was significantly different between the two groups. Conclusions: The present meta-analysis suggested that valsartan showed a tendency to be superior to other antihypertensive drugs in the improvement of insulin resistance, but the difference was not statistically significant. More large-scale studies with longer follow-up durations are warranted to confirm this effect.