Adherence to growth Hormone Treatment in the Transition Age: A Prospective Observational Multicenter Study

Objective To evaluate adherence to growth hormone (GH) treatment during the transition age in patients with permanent childhood-onset GH deficiency (COGHD). Design A prospective, multicenter, observational study conducted across 9 European endocrine centers. Methods Fifty-one patients aged 15–25 years with permanent COGHD, who had reached final height and continued recombinant human GH (r-hGH; 0.003-0.02 mg/kg/day), were monitored for 12 months using the Easypod™ device, which provides objective adherence data. Anthropometry, total cholesterol, LDL and HDL cholesterol, and IGF-1 SDS were measured at baseline and after one year. Patients with ≥9 months adherence data (n=41) were analyzed. Results Twenty-six patients (63%,16 males) had optimal adherence (≥85%, median, 98%; IQR, 91%–99%), and 15 (37%, 11 males) had suboptimal adherence (<85%, median, 70%; IQR, 47-80%). At baseline, suboptimal adherent patients had greater mean waist circumference (89.2 vs 78.2 cm) and lower mean IGF-1 SDS (-2.2 vs -1.5). After one year mean waist circumference (84.8 vs 76.7 cm), mean total cholesterol (185.1 vs 167.0 mg/dL), and mean LDL (111.6 vs 98.5) were higher in the suboptimal adherent group, whereas mean IGF-1 SDS was lower (-1.1 vs -0.2). Mean change in IGF-1 SDS after 1 year was +1.4 vs +0.9 in the two groups. Conclusions Over one-third of patients with permanent COGHD during transition show suboptimal adherence to GH therapy, associated with adverse metabolic markers and persistently lower IGF-1 levels. These findings highlight the importance of adherence monitoring and support targeted interventions to optimize long-term outcomes.