Prevalence and determinants of diabetic nephropathy in Korea: Korea national health and nutrition examination survey

Background: Diabetic nephropathy is a leading cause of end stage renal disease and is associated with an increased risk of cardiovascular mortality. It manifests as albuminuria or impaired glomerular filtration rate (GFR), and the prevalence of diabetic nephropathy varies with ethnicity. The prevalence of diabetic nephropathy and its determinants in Korean adults have not previously been studied at the national level. This cross-sectional study was undertaken to ascertain the prevalence and determinants of albuminuria and chronic kidney disease (CKD) in Korean patients with diabetes.

Methods: The Korea National Health and Nutrition Examination Survey (KNHANES) V, conducted in 2011, was used to define albuminuria (n=4,652), and the dataset of KNHANES IV-V (2008-2011) was used to define CKD (n=21,521). Selected samples were weighted to represent the entire civilian population in Korea. Albuminuria was defined as a spot urine albumin/creatinine ratio >30 mg/g. CKD was defined as a GFR <60 mL/min/1.73 m(2).

Results: Among subjects with diabetes, 26.7% had albuminuria, and 8.6% had CKD. Diabetes was associated with an approximate 2.5-fold increased risk of albuminuria, with virtually no difference between new-onset and previously diagnosed diabetes. Only systolic blood pressure was significantly associated with albuminuria, and old age, high serum triglyceride levels, and previous cardiovascular disease (CVD) were related with CKD in subjects with diabetes.

Conclusion: Korean subjects with diabetes had a higher prevalence of albuminuria and CKD than those without diabetes. Blood pressure was associated with albuminuria, and age, triglyceride level, and previous CVD were independent determinants of CKD in subjects with diabetes.