ESPE Abstracts

Context: Physiological growth hormone is secreted during the slow-wave sleep. Traditionally, growth hormone (GH) therapy is given in daily GH injections before sleep. This schedule better imitates the physiological diurnal variation of GH secretion and action. Late-night daily injections have been claimed to be associated with sleep disturbances and insomnia, yet there is no hard evidence supporting this contention. Morning and evening GH injections produce comparable effect on growth and IGF-1 levels.

Objective: Our objective was to evaluate evening vs. morning daily GH injections with respect to sleep quality, duration, and activity index in children treated with GH.

Design: An open-label, cross-over, randomized trial of 20 children (11 boys) 5-15 years of age with isolated growth hormone deficiency (n=11) and idiopathic short stature (n=9) treated with daily injections of GH (dose 33±6.9 mcg/kg/d) was performed. Each subject received 2 weeks of evening injections and 2 weeks of morning injections. Patients sleep quality, duration, and activity index were assessed by a 7-d actigraph on the second week of each treatment schedule.

Results: All subjects treated with morning or evening growth hormone injection slept well, within recommended ranges for sleep quality and duration. Total time in bed (min) (529.1±52 vs 519.5±57) , total sleep period (min) (515.7±519 vs 507.9±58.4), sleep efficiency (%) (93.2±3.0 vs 94.0±2.4) , sleep onset latency (min) (8.7±7.9 vs 7.3±6.6) , number of arousals per night (14.0±5.75 vs 13.2 ±5.9), and activity index in 24 hours (67.2±4.0 vs 67.0±5.0) during evening and morning GH injection schedule correspondently were comparable. No difference was found between growth hormone deficient and idiopathic short stature group. No difference was found between boys and girls.

Conclusions: With respect to sleep quality, duration and activity index were not affected by treatment schedules. We recommend injecting growth hormone according to the family convenience morning or evening or otherwise.