Growth hormone (GH) retesting and auxological data in 131 GH-deficient patients after completion of treatment

Abstract

GH state and auxological data after completion of GH therapy are reported in 131 patients (79 males, 52 females). They were treated from 1980-1994 for partial (n = 98) or complete (n = 33) GH deficiency (GHD), either idiopathic (n = 121) or organic (n = 10). A single stimulation test (clonidine+betaxolol) was used, and only 50 patients (38%) maintained a blunted response (GH peak below 10 micrograms/L). Although 9 of the 10 patients with organic GHD had an abnormal low GH peak, 67% of patients with idiopathic GHD normalized their GH secretion. This was particularly true of partial GHD patients (71% vs. 36% of complete GH-deficient patients). Based on a retest GH peak below 5 micrograms/L, only 23% of the patients were considered to be GH deficient and therefore candidates for GH treatment during adulthood. We found no significant difference between hormonal state at completion of treatment and initial GH deficiency, pubertal state, or sex, although we did find a significantly lower GH peak value before and after treatment in patients with elevated body mass index. Of the 14 obese children who were treated, 50% had an abnormally low serum insulin-like growth factor-I level, arguing for true GHD, and only two children remained obese at cessation of treatment. Auxological data showed that with a mean duration of treatment of 3.6 +/- 2.0 yr, patients classified as having complete GHD before treatment had significantly greater catch-up growth as expressed in SDS for height than patients with partial GHD (0.6 +/- 1.1 vs. 1.1 +/- 0.7 SDS, P < 0.05), and that boys grew better than girls (1.4 +/- 0.8 vs. 1.6 +/- 0.6 SDS) for height, P < 0.01). That catch-up growth was not correlated with the result of GH peak after cessation of treatment.