An evaluation of factors associated with proliferative diabetic retinopathy.

Many individual factors have been related to development of proliferative diabetic retinopathy. To evaluate possible interactions among these, a constellation of variables were studied in 22 patients with long duration of insulin-dependent diabetes mellitus for greater than 25 years, with minimal background diabetic retinopathy, and compared to 27 patients with insulin-dependent diabetes mellitus for a variable duration, but with bilateral proliferative retinopathy. The patients were compatible in age at onset of diabetes (12 +/- 2 in proliferative retinopathy group vs 12 +/- 1 yr in the background retinopathy group). Following initial standard statistical analyses, data were further analysed using Logistic Regression Analysis. In the proliferative retinopathy group males were more prevalent (2.9:1), and patients were treated with larger insulin doses (0.86 +/- 0.07 vs 0.59 +/- 0.04 U/Kg B.W., p less than 0.001). Systemic hypertension and neuropathy were more prevalent (p less than 0.02 and less than 0.004 respectively), and diastolic blood pressure was higher (87 +/- 3 vs 75 +/- 2, p less than 0.01). In the same group diet was higher in carbohydrate and the ratio of polyunsaturated to saturated fats was lower (p less than 0.03, less than 0.05 respectively). HbA1 was higher (0.127 +/- 0.004 vs 0.110 +/- 0.004%, p less than 0.004), but the mean of all available plasma glucose values was not different. Impaired renal function expressed by higher BUN, serum creatinine, and urinary protein and lower creatinine clearance was observed. Nerve conduction parameters were more significantly impaired and plasma triglycerides were higher (1.74 +/- 0.2 vs 0.85 +/- 0.1 mmol/l, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)