Growth hormone suppression and nonproliferative diabetic retinopathy: a preliminary feasibility study

We used the long acting somatostatin analogue SMS 201-995 in order to examine the feasibility and effect of medical suppression of growth hormone in nonproliferative diabetic retinopathy. Six insulin-dependent diabetic subjects with nonproliferative retinopathy were studied. After eight weeks of SMS 201-995 administration, 24-hour integrated plasma growth hormone concentrations had declined by 47.0 +/- 9.3% of pretreatment values (p less than 0.01), and insulin requirements fell from 40.7 +/- 6.7 units per day to 32.2 +/- 6.9 units per day (p less than 0.01). Plasma levels of somatomedin-C were low before SMS 201-995 (0.5 +/- 0.1 U/ml) and remained unchanged at eight weeks (0.6 +/- 0.1 U/ml; p = ns). During SMS 201-995 administration, best corrected visual acuity improved in both right eyes (53.8 +/- 2.57 to 59.8 +/- 0.7 letters, p less than 0.05) and left eyes (54.8 +/- 2.8 to 61.7 +/- 1.23 letters, p less than 0.03). Fluorescein angiography and stereo fundus photography demonstrated concurrent improvement in retinopathy level in only two subjects. Following cessation of SMS 201-995 treatment, visual acuity returned to pretreatment levels in both right eyes (54.5 +/- 2.4 letters, p = ns compared to baseline) and left eyes (55.8 +/- 2.6 letters, p = ns compared to baseline). These results demonstrate that growth hormone was only partially suppressed by SMS 201-995 in insulin-dependent diabetic subjects.(ABSTRACT TRUNCATED AT 250 WORDS)