Association of baseline body mass index with growth responses to growth hormone therapy in children with growth hormone deficiency

OBJECTIVES: This study aimed to evaluate the association of baseline body mass index (BMI) status with long-term growth and metabolic outcomes during growth hormone (GH) therapy in children with GH deficiency (GHD). METHODS: From the LG Growth Study, we analyzed 155 children with GHD receiving GH for ≥36 months after age-based propensity score matching (78 elevated-BMI; 77 normal-BMI). Multivariable regression assessed baseline BMI-standard deviation score (SDS) in relation to 36-month changes in height SDS by bone age (BA). Group comparisons assessed longitudinal growth and metabolic outcomes; separate matched obesity and overweight analyses were exploratory. RESULTS: Baseline height SDS by chronological age (CA) did not differ significantly between groups (-2.33 ± 0.58 vs. -2.45 ± 0.65; p=0.1464), whereas height SDS by BA was higher in the elevated-BMI group (0.00 ± 1.68 vs. -0.73 ± 1.28; p=0.0131). Height velocity trajectories were similar (group-by-time p=0.9585). Height SDS by CA improved comparably between groups, whereas ΔHeight SDS by BA differed significantly at 12 months (p=0.0387) and 36 months (p=0.001). Higher baseline BMI-SDS was associated with a lower 36-month change in height SDS by BA in the adjusted model (β=-0.3525; p=0.0216). BMI-SDS decreased in the elevated-BMI group during the first year (p<0.0001), and total cholesterol decreased in both groups. CONCLUSIONS: Higher baseline BMI-SDS was associated with a lower 36-month change in height SDS by BA during GH therapy, while CA-based height gains did not differ significantly between groups.