Final height in non-growth hormone deficient children treated with growth hormone. The Italian Multicentre Study Group.

OBJECTIVE

To evaluate the final height of nongrowth hormone deficient (N-GHD) children treated with growth hormone (GH).

DESIGN

Multicentre retrospective study.

PATIENTS

71 (54M/17F) N-GHD children (peak GH after pharmacological stimulation > 14-24 mU/l) who had been treated for 4.19 +/- 0.14 years with GH (0.69 +/- 0.02 IU/kg/week).

MEASUREMENTS

Height (H) and height velocity (HV) expressed as standard deviation score (SDS) for chronological age (CA) and bone age (BA), BA/CA ratio, and predicted adult height (PAHSDS) were evaluated before and during treatment, and at each pubertal stage. Target height (TH), and final height (FH) were also calculated, and expressed as SDS.

RESULTS

In the whole group, HSDS for CA increased significantly after the first year on GH, and remained significantly increased for 4 years. This did not occur to HSDS for BA, owing to a significant increase in BA/CA after the first year of therapy. In addition, this increase coincided with stages 4 and 5 of puberty. HVSDS for CA and BA also increased significantly after the first year of treatment, and remained significantly elevated for 4 years. PAHSDS did not change significantly during treatment. FHSDS (-1.69 +/- 0.07) was similar to PAHSDS (-1.6 +/- 0.12) and target height (THSDS) (-1.46 +/- 0.08). FHSDS was > or = THSDS in 36.6% of the patients, and > or = initial PAHSDS in 34.5%. Male patients were subdivided into 2 groups (A and B). Patients in Group A (n = 26) started treatment at puberty, while group B (n = 28) consisted of subjects who started therapy during prepubertal years. Height, height velocity and predicted adult height showed the same pattern as in the whole group, in each subgroup. BA/CA advanced significantly in group A after the second year on GH and in group B, after at least 3 years of therapy. FHSDS, THSDS, and PAHSDS were similar in both groups (-1. 7 +/- 0.13, -1.29 +/- 0.2 and -1.39 +/- 0.15 in group A and -1.48 +/- 0.11, -1.85 +/- 0.15 and -1.36 +/- 0.12 in group B, respectively). However, in group B (prepubertal), FHSDS was > or = initial PAHSDS in 60% of the patients and > or = THSDS in 40.7%, while in group A (pubertal), FHSDS was > or = initial PAHSDS only in 22.7% of the patients and > or = THSDS in 34.6%. FHSDS was found to be correlated with THSDS, PAHSDS at the onset of treatment, and after 1 year of treatment. The age at the beginning of puberty, and the duration of puberty were appropriate in all groups.

CONCLUSIONS

GH treatment was effective in increasing height velocity of short non-GH-deficient children, but final height was not definitely improved with respect to initial predicted adult height.