Comparison of the effect between pioglitazone and metformin in treating patients with PCOS:a meta-analysis

Pioglitazone was used to treat patients of PCOS in many researches, but the treatment has not been recognized by public or recommended by all the guidelines. We conducted a meta-analysis of the related literatures to objectively evaluate the clinical effectiveness and safety by comparing pioglitazone with metformin administrated by PCOS patients. Searches were performed in Cochrane Library, EMBASE and PubMed (last updated December 2016). Eleven studies among 486 related articles were identified through searches. Fixed effects and random effects models were used to calculate the overall risk estimates. The results of the meta-analysis suggest that improvement of the menstrual cycle and ovulation in pioglitazone treatment group was better than metformin group [OR = 2.31, 95% CI (1.37, 3.91), P < 0.001, I (2) = 41.8%]. Improvement of the F-G scores in metformin treatment group was better than pioglitazone group [SMD = 0.29, 95% CI (0.0, 0.59), P = 0.048, I (2) = 0.0%]. BMI was more elevated in pioglitazone group than in metformin group [SMD = 0.83, 95% CI (0.24, 1.41), P = 0.006, I (2) = 82.8%]. There were no significant differences of the other data between the two groups. This meta-analysis indicated that pioglitazone ameliorated menstrual cycle and ovulation better than metformin and metformin ameliorated BMI and F-G scores better than pioglitazone in treating patients with PCOS. Pioglitazone might be a good choice for the patients with PCOS who were intolerant or invalid to metformin for the treatment.