Diabetic retinopathy and renal function in Chinese type 2 diabetic patients

To evaluate associations of diabetic retinopathy (DR) with renal function in Chinese type 2 diabetic patients.

This cross-sectional study enrolled 523 type 2 diabetic patients. All patients underwent ophthalmic examination to assess DR [normal, non-proliferative DR (NPDR), proliferative DR (PDR)]. The renal function measurements were taken in urine and blood. The estimated glomerular rate (eGFR) and albumin/creatinine ratio (ACR) were calculated using standard formulas. The chronic kidney disease (CKD) was defined as eGFR < 60 mL/min/1.73 m(2), and microalbuminuria was defined as ACR > 17 for males and ACR > 25 for females. The associations of DR with renal function and CKD were assessed by regression models, without and with the adjustment of risk factors for CKD.

In multivariate analysis, increasing severity of DR was significantly associated with lower eGFR (p < 0.001), higher level of retinol-binding protein (p < 0.001), and larger ACR (p < 0.0001). The DR was significantly associated increased risk of CKD with odds ratio of 2.22 (95% CI 1.01-4.86) for NPDR and 3.52 (1.30-9.55) for PDR.

Among Chinese type 2 diabetic patients, increasing DR severity is significantly associated reduced kidney function and increased risk of CKD. These associations are independent of risk factors for CKD, suggesting that assessment of DR may provide useful information on the renal function and risk of kidney disease.