Stimulation of collagen synthesis and linear growth by growth hormone in glucocorticoid-treated children

Impaired linear growth and skeletal maturation associated with chronic glucocorticoid therapy may result from (1) inhibited insulin-like growth factor 1 (IGF-1) activity; (2) impaired type 1 collagen synthesis; or (3) suppressed growth hormone (GH) secretory response to growth hormone-releasing hormone. Each mechanism could potentially be improved by exogenous GH treatment. Seven slowly growing glucocorticoid-treated children received recombinant DNA human GH (0.3 mg/kg/per week) for 6 to 21 (mean 13.1 +/- 4.9) months. Height, weight, IGF-1 activity, glycosylated hemoglobin level, and C-terminal type 1 procollagen level were measured every 3 months and growth velocity was calculated. Skeletal maturation and 2-hour postprandial serum glucose and insulin levels were assessed every 6 months. All patients showed increased growth velocity during treatment with GH. Mean growth velocity increased from 3.43 +/- 0.65 cm/y to 6.72 +/- 0.84 cm/y with GH therapy (P less than .005). Growth velocity standard deviation scores corrected for bone age (P less than .005), IGF-1 levels (P less than .05), and C-terminal type 1 procollagen levels (P less than .005) also increased with GH therapy. C-terminal type 1 procollagen levels correlated well with growth velocity (r = .652) while IGF-1 levels did not (r = .17). Glycosylated hemoglobin levels remained unchanged, but 2-hour postprandial glucose levels rose during GH treatment. Slowly growing glucocorticoid-treated children receiving GH therapy increased growth velocity for 6 to 21 months. Initially diminished C-terminal type 1 procollagen levels rose with GH therapy, a change which corresponded with growth acceleration.(ABSTRACT TRUNCATED AT 250 WORDS)