ODP386 Growth Velocity and Growth Hormone Deficiency During Puberty

BACKGROUND: A subnormal growth velocity (GV) is a characteristic feature of growth hormone deficiency (GHD). During puberty growth hormone (GH) levels increase markedly in response to sex hormone secretion. The normal range for GV declines during childhood, increases during puberty with peak levels at mid-puberty. Hence, pubertal status rather than age alone must be considered in the evaluation of GV in children and adolescents. In most cases, a diagnosis of GHD is established by a subnormal response in GH levels following a stimulation with two pharmacological agents. OBJECTIVE: We determined the reliability of GV as a predictor of GHD during puberty. METHODS: We conducted a retrospective study of pubertal children and adolescents who underwent a GH stimulation test in our pediatric endocrinology clinic. Seventy-nine subjects (57 boys and 22 girls) were included in this study. Bone age was determined for all patients. Serum levels of insulin like growth factor-1 (IGF-1) were obtained prior to GH stimulation test. Serum IGF-1 levels, expressed as a standard deviation score were compared to the IGF-1 levels expected chronological age (CA), height age (HA), and bone age (BA). Serum GH levels were determined following the administration of arginine and levodopa. GHD was established by a peak GH level <10 ng/mL. IBM SPSS Statistics software version 28. 0. 0. 0 (190) was used for data analysis. RESULTS: Subjects ranged in age from 7.3-17.9 years. Thirty-nine patients (49.4%) had GV < 10 th percentile for CA; Forty patients (50.6%) had GV <10 th percentile for BA. Sixty percent of patients with GV <10 th percentile for CA had GHD. A similar number (59%) of patients with normal GV for CA also had GHD. Among patients with GV <10 th percentile for BA, 72.5% of subjects had GHD. By contrast, the percentage of patients who had normal GV for bone age and GHD (46.2%) was significantly less than that of subjects with GV <10 th percentile for BA (p = 0. 015). Positive predictive value, negative predictive value, sensitivity and specificity for GV <10 th percentile for BA in the diagnosis of GHD were 72.5%, 53.8%, 61.7%, and 65.6%, respectively. With respect to the diagnostic value of serum IGF-1, when the area under the ROC curve was used to measure how well the serum IGF-1 standard deviation score distinguished between GHD and normal, serum IGF-1 standard deviation score for CA, HA, and BA were not predictive of GHD (p = 0.1, 0.47, and 0.27, respectively). CONCLUSIONS: During puberty, slow growth velocity for bone age (but not slow growth velocity for chronological age) was useful to predict a diagnosis of growth hormone deficiency. Presentation: No date and time listed