Background/aims: Growth hormone (GH) treatment regimens do not account for the pubertal increase in endogenous GH secretion. This study assessed whether increasing the GH dose and/or frequency of administration improves pubertal height gain and adult height (AH) in children with low GH secretion during stimulation tests, i.e. idiopathic isolated GH deficiency.
Methods: A multicenter, randomized, clinical trial (No. 88-177) followed 111 children (96 boys) at study start from onset of puberty to AH who had received GH 33 µg/kg/day for ≥1 year. They were randomized to receive 67 µg/kg/day (GH(67)) given as one (GH(67×1); n = 35) or two daily injections (GH(33×2); n = 36), or to remain on a single 33 µg/kg/day dose (GH(33×1); n = 40). Growth was assessed as heightSDSgain for prepubertal, pubertal and total periods, as well as AHSDS versus the population and the midparental height.
Results: Pubertal heightSDSgain was greater for patients receiving a high dose (GH(67), 0.73) than a low dose (GH(33×1), 0.41, p < 0.05). AHSDS was greater on GH(67) (GH(67×1), -0.84; GH(33×2), -0.83) than GH(33) (-1.25, p < 0.05), and heightSDSgain was greater on GH(67) than GH(33) (2.04 and 1.56, respectively; p < 0.01). All groups reached their target heightSDS.
Conclusion: Pubertal heightSDSgain and AHSDS were dose dependent, with greater growth being observed for the GH(67) than the GH(33) randomization group; however, there were no differences between the once- and twice-daily GH(67) regimens. © 2014 S. Karger AG, Basel.