RT Journal A1 Singh S, Segal JB T1 Thiazolidinediones and macular edema: Comment on “association between thiazolidinedione treatment and risk of macular edema among patients with type 2 diabetes” JF Archives of Internal Medicine JO Archives of Internal Medicine YR 2012 FD July 9 VO 172 IS 13 SP 1011 OP 1013 DO 10.1001/archinternmed.2012.2461 UL http://dx.doi.org/10.1001/archinternmed.2012.2461 AB The thiazolidinediones, rosiglitazone and pioglitazone, are peroxisome proliferator–activated receptor γ (PPAR-γ) agonists. They effectively reduce glycated hemoglobin among patients with type 2 diabetes mellitus by approximately 1 to 1.5 percentage points compared with placebo and are used as second-line treatment agents. However, rosiglitazone and pioglitazone have been associated with peripheral edema, congestive heart failure, and bone fractures.1- 2 An increased risk of myocardial ischemia has been attributed to rosiglitazone.2 An increased risk of bladder cancer associated with pioglitazone is noted in the current label. Spontaneous reports of macular edema with the use of thiazolidinediones has resulted in regulatory warnings on this potential association. However, the causality remains unclear.