Extended follow-up is crucial for diagnosing growth hormone deficiency after traumatic brain injury in children and adolescents

Background The rate of growth hormone (GH) deficiency (GHD) after traumatic brain injury (TBI) among children and adolescents remains uncertain, partly because of limited follow-up. Objective To evaluate a novel diagnostic approach for post-TBI GHD based on height velocity (HV), IGF-1 levels, and response to recombinant human growth hormone (rhGH), and to estimate its incidence. Methods In this prospective, longitudinal study, 31 patients (aged 2.4–18.6 years) hospitalized for TBI underwent complete clinical and hormonal evaluations every 3 months for ≥1 year. Eleven were excluded because they had reached their final or near-final height. The criteria for GHD diagnosis included (a) HV below −1 SDS, (b) at least one IGF-1 level below −1 SDS during the first 2 years after TBI, and (c) increase in HV (>2 SDS) and IGF-1 (>1 SDS) during rhGH therapy. Results Four patients met criteria for GHD. During the second year after TBI, HV-SDS ranged from −1.42 to −3.41, and height-SDS declined. All patients had at least one IGF-1 value below −1 SDS, while GH stimulation tests were often discordant with HV and IGF-1 levels. Therapy with rhGH led to marked increases in HV-SDS (≥2.73) and IGF-1-SDS (≥1.34) in all 4 patients. Fourteen children maintained normal HV, despite abnormal stimulation tests in some cases. Conclusion Extended HV monitoring combined with IGF-1 assessment and therapeutic rhGH response was more effective than GH stimulation tests alone for diagnosing post-TBI GHD. The GHD incidence was 13%, underscoring the importance of extended auxological follow-up in pediatric patients after TBI.