The relationship between diabetic retinopathy and diabetic nephropathy in a population-based study in Korea (KNHANES V-2, 3)

PURPOSE To determine the risk factors for and relationship between diabetic retinopathy (DR) and diabetic nephropathy (DN), including microalbuminuria and overt nephropathy, in a population-based study of diabetes mellitus (DM) patients in Korea. METHODS This was a population-based, cross-sectional study. From the fifth (2011, 2012) Korea National Health and Nutrition Examination Survey (KNHANES), 971 participants with type 2 DM were included. The prevalence of DR and DN was determined. Multivariate logistic regression was performed to determine risk factors, including DR, associated with DN in the Korean population. RESULTS In DM patients, we observed a prevalence of 20.0% for any DR and 3.8% for proliferative diabetic retinopathy (PDR). Microalbuminuria prevalence was 19.3% and overt nephropathy prevalence was 5.5%. The risk factors of microalbuminuria were presence of hypertension; higher systolic blood pressure, serum hemoglobin A1c (HbA1c), and serum blood urea nitrogen level; as well as the presence of PDR. The risk factors of overt nephropathy were long duration of DM; high levels of HbA1c, systolic blood pressure, total cholesterol, and serum creatinine; as well as the presence of DR CONCLUSIONS: Proliferative diabetic retinopathy is associated with microalbuminuria and DR is associated with overt nephropathy in Korean DM patients. Our findings suggest that when an ophthalmologist finds the presence of DR or PDR, timely evaluation of the patient's renal status should be recommended.