Somatomedin-C and diabetic retinopathy

To investigate the relationship between the plasma somatomedin-C level and diabetic retinopathy, especially in different stages of the disease, plasma somatomedin-C levels were measured in 72 patients with noninsulin-dependent diabetes mellitus accompanied by or without retinopathy and in 37 normal control subjects. The stage of retinopathy was assessed by ophthalmoscopy and fluorescein angiography. Plasma somatomedin-C levels were significantly greater in the diabetic patients with retinopathy than in the age-matched normal controls (P less than 0.01). Plasma somatomedin-C level in the patients with proliferative retinopathy was 0.60 +/- 0.30 (mean +/- SD) IU/ml (n = 24), which was significantly greater than that in the normal controls (0.41 +/- 0.18 IU/ml) (P less than 0.01). However, the patients in different stages of diabetic retinopathy did not differ significantly from each other in their plasma somatomedin-C levels.