Short-term treatment of short stature and subnormal growth rate with human growth hormone.

Forty-eight children with short stature, growth rate less than 4 cm/yr, and normal growth hormone response to secretagogues were given exogenous human growth hormone (hGH) for 6 months to determine its effect on the short-term growth rate in these children. All except three had an increase in growth rate with hGH therapy. The mean +/- SD pretreatment growth rate (3.4 +/- 0.8 cm/yr) was significantly less than either the growth rate during 6 months of hGH therapy (6.9 +/- 2.6 cm/yr) or after therapy (4.1 +/- 1.8 cm/yr). Several patterns of response were observed after treatment was stopped: the mean growth rate in 22 children decreased after treatment but remained above basal rates, the mean growth rate in seven children was similar to the rates during treatment, and the mean growth rate in 16 children was less than basal rates. Twenty children received therapy for an additional 6 months and had a mean increase in growth rate from 3.6 +/- 1.3 to 6.7 +/- 2.4 cm/yr. The decreased growth rate after discontinuation of treatment and increased rate with resumption of therapy indicates that maintenance of the increased growth rate might be dependent on continuation of hGH therapy.