RESUMO
Growth hormone and growth factors have been implicated in the pathogenesis of diabetic retinopathy. Hypophysectomy has been proposed as a treatment for proliferative diabetic retinopathy unresolved by panretinal photocoagulation (PPC). SMS 201-995, a long acting somatostatin analogue which slows down growth hormone secretion, may provide a non-invasive therapy for these rare cases. To assess this possibility, we studied the feasibility and efficiency of long-term SMS 201-995 treatment in diabetics. SMS 201-995 was injected subcutaneously with a continuous pump system at a dose of 400 micrograms/d into 4 insulin dependent diabetic patients suffering from proliferative diabetic retinopathy progressing despite a pan-photocoagulation. The mean age of these patients was 29 +/- 3 years and mean disease duration 18 +/- 3 years. Treatment periods lasted from 6 to 20 months (mean 15 months). Mean 24-hour growth hormone levels decreased by 57% after only one month of treatment (7.4 +/- 1.9 mU/l to 3.2 +/- 0.9 mU/l). The decline continued up to the third month. After the sixth month, signs of resistance to the drug were noted. The frequency of 24-hour GH peaks over 10 mU/l followed a parallel pattern. No rebound was observed when the treatment was progressively discontinued. In 2 patients neovascularization stopped. In the other 2 the process regressed. In all treatment had beneficial effects on the retina. Overall visual acuity improved (7.8 +/- 0.8/10e vs 5.5 +/- 0.8/10e). These effects were obtained within 3 to 6 months. Glycosylated haemoglobin levels did not change (8.8 +/- 1.3% to 9.0 +/- 0.8%). Insulin doses decreased 41% (46.5 +/- 1.7 U/d to 27.3 +/- 3.0 U/d). No severe hypoglycaemia occurred.(ABSTRACT TRUNCATED AT 250 WORDS)