The impacts of thiazolidinediones on circulating C-reactive protein levels in different diseases: A meta-analysis

Objectives: Thiazolidinediones (TZDs), including rosiglitazone and pioglitazone, are widely used as antidiabetic agents. Here we present an updated meta-analysis of the respective effects of rosiglitazone and pioglitazone on the levels of C-reactive protein (CRP), a biomarker and predictor of CAD risks. Methods and results: PubMed and EMBASE were systematically searched using the terms C-reactive protein and rosiglitazone or pioglitazone or thiazolidinedione. A total of 59 rosiglitazone studies and 36 pioglitazone studies were included for evaluation. These were classified as 2-group studies and 1-group studies according to their study design. Standard mean difference (SMD) of CRP and 95% CI were calculated to evaluate the effect of TZDs on CRP. The overall SMD for rosiglitazone treatment is -0.392 (95% CI, [-0.446, -0.338]) in 2-group studies and -0.424 (95% CI, [-0.501, -0.346]) in 1-group studies. The overall SMD for pioglitazone treatment is -0.577 (95% CI, [-0.732, -0.421]) in 2-group studies and -0.327 (95% CI, [0.439, 0.216]) in 1-group studies. Moreover, TZDs were found to significantly reduce CRP levels in both diabetes mellitus (DM) and non-DM patients. Conclusions: Our meta-analysis suggested that both rosiglitazone and pioglitazone significantly decrease serum CRP levels. TZDs presented their CRP-lowering effect in both DM and non-DM patients. (C) 2010 Elsevier Ireland Ltd. All rights reserved.