Purpose: To determine the ocular safety of glitazones in patients with diabetes, we investigated the association of diabetic macular edema (DME) in a large population of glitazone users.
Design: Prospective cohort study.
Methods: The study was conducted at Kaiser Permanente Southern California. About 170,000 persons with diabetes were identified using the Diabetes Case Identification Database. Glitazone drug use was obtained from the pharmacy database. The main outcome measure was the development of macular edema (ME). The chi2 test was used to compare proportions and t tests were used for means. Logistic regression analysis was used to adjust for potential confounding variables.
Results: In 2006, there were 996 new cases of ME. Glitazone users were more likely to develop ME in 2006 (odds ratio [OR], 2.6; 95% confidence interval [CI], 2.4 to 3.0). After excluding patients who did not have the drug benefit, did not have an eye exam, and had a HgA1c <7.0, glitazone use was still associated with an increased risk of developing ME (OR, 1.6; 95% CI, 1.4 to 1.8).
Conclusion: The current study appears to show that the glitazone class of drug is associated with DME. After adjusting for confounding factors of age, glycemic control, and insulin use, glitazones are still modestly associated with DME. A more in-depth study will need to be done to evaluate the role of other confounding factors. When treating patients with DME, ophthalmologists should consider the role of the glitazones.