COMPARATIVE EFFECTIVENESS OF ROSIGLITAZONE (ROSI) AND PIOGLITAZONE (PIO) IN TREATMENT OF TYPE 2 DIABETES: A SYSTEMATIC REVIEW AND META-ANALYSIS

Purpose: to analyzed the available data from head-to-head studies to compare the effects of the two thiazolidinediones (TZD) in terms of cardiovascular clinical and surrogate outcomes, and safety.

Method: An electronic literature search of the following bibliographic databases was performed to identify randomized controlled trials (RCT) and observational studies on thiazolidinediones for adult patients with type II diabetes, published between 1990 and 2008, using Medline, EMBASE, Thomson’s Biosis Previews, Wiley’s Cochrane Library, and the Centre for Reviews and Dissemination databases. Websites of professional associations were also searched, and grey literature was identified from several sources. The assessment of study eligibility and methodological quality was performed by two independent reviewers. When two or more comparable studies were identified, a pooled estimate of effect was obtained in a meta-analysis. A random effects model was used for pooled estimate of effect sizes and their confidence intervals.

Result: Of 1758 citations identified by systematic search, 10 RCTs and 10 observational studies remained in the review after applying the study inclusion and exclusion criteria. The results of our review showed that patients who received ROSI and PIO were in similar risks of developing MI, MI/CR or stroke. One of the observational studies included in our review showed that ROSI users were 11% more likely to experience congestive heart failure (CHF) after treatment and 6% more likely to die from any cause, as compared to the patients on PIO.  The results of meta-analyses showed both TZDs had similar glycemic control effects. PIO was found to result in better improvement in triglyceride and HDL levels as compared to ROSI. The pooled analysis of RCT data indicated the patients on ROSI monotherapy had significantly less weight gain and BMI than the patients on PIO monotherapy. No statistically significant differences were found between two TZDs in terms of hypoglycemic events, hepatotoxicity, peripheral or pulmonary edema, or systolic blood pressure.

Conclusion: There was no conclusive evidence to demonstrate comparative benefits or harms of the two TZDs in terms of ischemic heart disease More head-to head studies are needed to reduce the current uncertainty about the cardiovascular effects of ROSI and PIO.