The relationship between diabetes mellitus and exfoliation syndrome in a United States Veterans Affairs population: A case-control study

PURPOSE: Earlier studies suggest that an inverse relationship exists between diabetes mellitus and exfoliation syndrome (ES). We evaluated the relationship between diabetes mellitus and ES while controlling for important covariates. In addition, we investigated whether glucose control, as measured by glycosylated hemoglobin (HbA1c) levels, differed between the subset of diabetic patients with and without ES. PATIENTS AND METHODS: This retrospective case-control study included outpatients seen in Veterans Affairs Boston Healthcare System eye clinics. Exfoliation cases (n=328) and controls (n=328) were drawn from the same clinic and matched for age. For all participants, we ascertained diabetes status, sex, race, body mass index, and glaucoma status. Among patients with diabetes mellitus, we collected the 5 most recent HbA1c levels and type of diabetes control. RESULTS: Diabetes mellitus was present in 96 (29.2%) cases and in 114 (34.8%) controls. In multivariate analysis, no statistically significant relationship between diabetes mellitus and ES (OR=0.77; 95% CI, 0.55-1.07) was identified. When glaucoma status was added as a covariate, the results were essentially unchanged (OR=0.81, 95% CI, 0.57-1.14). Adjusted mean HbA1c levels were similar in diabetic patients with (6.85%; 95% CI, 6.66-7.04) and without (7.05%; 95% CI, 6.87-7.22) ES (P=0.14). CONCLUSION: In this predominately white male population, we did not observe a statistically significant relationship between diabetes mellitus and ES. In addition, HbA1c levels did not vary among diabetic patient based on exfoliation status.