Effect of glycemic control on serum insulin-like growth factors in diabetes mellitus.

We investigated the effect of improving glycemic control on serum concentrations of insulin-like growth factors I and II (IGF-I and IGF-II). In 22 adults followed during an intensive home glucose monitoring program for 6 mo, no effect of improving control was seen on either IGF-I or IGF-II. Similar results were obtained in young diabetic children less than 10 yr of age and in diabetic adolescents with detectable puberty before entering the study. In older diabetic children without evidence of puberty before treatment (Tanner prepubertal stage 1), initial IGF-I concentrations were low, but increased during establishment of glycemic control. Puberty developed during therapy in this latter group. Our data do not support a "global" effect of glycemic control on serum IGF-I in diabetic patients. Increases of IGF-I with better glycemic control appear most likely to occur when the metabolic consequences of diabetes have suppressed normal pubertal increases of IGF-I. IGF-II concentrations were unaffected by glycemic control in all subjects.