Discontinuation of growth hormone (GH) treatment during the transition phase is an important factor determining the phenotype of young adults with nonidiopathic childhood-onset GH deficiency.

CONTEXT: Little is known about the impact of childhood-onset GH deficiency (GHD), in particular the duration of GH cessation during the transition phase, on adult phenotype.

OBJECTIVE: We investigated the association between the manifestations and management of GHD during childhood/adolescence and the clinical features of GHD in adulthood. DESIGN/SETTING/PATIENTS/INTERVENTION: Patients with reconfirmed childhood-onset GHD who resumed GH treatment as adults were identified from two sequential databases (n = 313). The cohort was followed up longitudinally from GH start in childhood to reinitiation of treatment in adulthood and 1 yr beyond. Analyses were performed in the total cohort and in subgroups of patients with idiopathic GHD (IGHD) and non-IGHD. The cohorts were stratified based on duration of GH cessation (short, < or = 2 yr; long, > 2 yr).

MAIN OUTCOME MEASURES: Regimen of pediatric GH administration, duration of GH interruption, IGF-I sd score, lipid concentrations, and quality of life were measured.

RESULTS: Mean duration of GH interruption was 4.4 yr. IGF-I sd score in adulthood was related to severity of childhood GHD. In non-IGHD patients, a longer duration of GH interruption was associated with a worse lipid profile (P < 0.0001). Non-IGHD patients who gained more height during childhood GH treatment reported better quality of life than those who gained less height (P < 0.05).

CONCLUSIONS: Pediatricians should tailor GH treatment, not only for its beneficial effect on growth but also for future health in adulthood. In adults with reconfirmed GHD, particularly those with non-IGHD, early recommencement of GH should be considered.