Favorable cardiovascular effects of pioglitazone: a meta-analysis

Katya Hristova Uzunova*, Elena Pavlova Filipova, Krassimir Boytchev Kalinov & Toni Yonkov Vekov

Type 2 diabetes mellitus is caused by insulin resistance and β cell failure. Pioglitazone and other thiazolidinediones are the antidiabetic agents that increase insulin sensitivity, reduce blood glucose and hemoglobin A1c levels, inhibit adipose-tissue lipolysis, decrease microalbuminuria, inhibit inflammation, decrease blood pressure and reduce adverse cardiovascular risk. The objective of this review was systematic evaluation of the effect of pioglitazone on mortality and cardiovascular events in the patients with diabetes mellitus. In the analysis were included randomized, controlled studies after systematic literature search in electronic databases. Risk ratios with 95% confidence intervals (CI) were calculated, using the random effect model. Statistical heterogeneity across all the studies was tested with the I2 statistics. Pioglitazone was associated with statistically significant reduction in non-fatal coronary events (defined as myocardial infarction, unstable angina or coronary revascularization): RR 0.62, 95% CI (0.43, 0.89), but significant heterogeneity was found (p=0.00, I2=80%). Mortality rate was not significantly different between pioglitazone users and non-users (RR 0.87, 95% CI (0.62, 1.23). Overall risk for non-fatal heart failure was slightly increased (RR 1.31, 95% CI (1.17, 1.47)). No significant heterogeneity was found for any of these analysis (I2=47%, p=0.06 and I2=10%, p=0.35). Pioglitazone is and should remain an important agent within the modern management of type 2 diabetic patients, especially in those at elevated cardiovascular risk.