Retinopathy and nephropathy in insulin-dependent diabetics: an inconsistent relationship?

The association between retinopathy and nephropathy was investigated in a retrospective study of 52 insulin-dependent diabetics with preproliferative or proliferative retinopathy and in 48 patients without or with background retinopathy. The duration of diabetes was 23.2 +/- 1.0 years (mean +/- SEM) and 22.0 +/- 1.2 years in the two groups. Patients in the retinopathy group showed a higher frequency of detectable nephropathy and were more often treated with antihypertensive drugs. However, a high proportion (35%) of patients with proliferative retinopathy did not show any detectable signs of nephropathy. Furthermore, nephropathy did not seem to develop in patients with retinopathy during an observation period of up to 9 years. The data suggest that the factors underlying the development of retinal and renal microangiopathy might be of different origin.