Abstract
Purpose: :
We examined the association between serum bilirubin levels and diabetic retinopathy in patients with diabetes and impaired glucose metabolism.
Methods: :
A total of 1,672 Japanese subjects, aged 40 years or older and with diabetes or impaired glucose metabolism (according to 2003 American Diabetes Association criteria), were stratified into four groups according to serum bilirubin quartiles, and diabetic retinopathy was assessed by ophthalmic examination.
Results: :
Of the subjects, 70 had diabetic retinopathy. The age, sex, and 2-h plasma glucose-adjusted prevalence of diabetic retinopathy decreased significantly as the quartiles of bilirubin levels increased. In multivariate analyses, the risk of diabetic retinopathy was significantly lower in the highest bilirubin quartile than in the lowest after adjustment for a number of confounding factors (odds ratio, 0.22; 95% confidence interval: 0.08-0.62).
Conclusions: :
Our findings suggest that elevated serum bilirubin levels significantly prevent the development of diabetic retinopathy, independent of plasma glucose and hemoglobin A1c.
Keywords: diabetic retinopathy • protective mechanisms • antioxidants