Background: Insulin resistance(IR) precedes and plays a pivotal role in type 2 diabetes and occurs early in the natural history of the disease. This investigation compared the efficacy of thiazolidinediones(TZDs) and metformin(MET) in the effect of insulin resistance(IR) as assessed using the homeostasis model assessment(HOMA) index in drug-naive type 2 diabetic patients. Material and Methods: We searched the MEDLINE, EMBASE, and Cochrane Library databases to identify studies published before February 2015 that investigated the use of TZDs and MET to determine the effect on the HOMA index in drug-naive type 2 diabetics. Parameters on IR, HbA1c, BMI and waist circumference were collected. Review Manager 5.3 and Stata 12.0 were used to perform the meta-analysis. Fixed and random effects models were applied to various aspects of the meta-analysis, which assessed the therapeutic effects of the two types of drug using the HOMA index in type 2 diabetics. The meta-analysis included nine randomized controlled short trials (12~18 weeks). Results: Participants comparisons before and after treatment with TZDs and MET revealed that TZDs and MET treatments could improve HOMA index and lower FPG, FPI, HbA1c in drug-naive type 2 diabetics with lifestyle intervention. No significant differences in the therapeutic effects of these two types of drug on HOMA index, HbA1c, BMI and waist circumference were observed. Conclusions: On the basis of life intervention, either TZDs or MET might be a good choice in drug-naive type 2 diabetics.

Keywords: Diabetes Mellitus, Type 2, Insulin Resistance, Thiazolidinediones