Factors associated with response to growth hormone in pediatric growth disorders: results of a 5-year registry analysis

Context Growth hormone (GH) therapy can increase linear growth in patients with growth hormone deficiency (GHD), Turner syndrome (TS), Noonan syndrome (NS), and Prader-Willi syndrome (PWS), although outcomes vary by disease state.

Objective To assess growth and identify factors associated with growth response with long-term GH therapy.

Methods Data from pediatric patients with GHD, TS, NS, and PWS obtained at GH treatment initiation (baseline) and annually for 5 years in the ANSWER Program and NordiNet® IOS were analyzed retrospectively. Height standard deviation score (HSDS) was assessed over time, and multivariate analyses determined variables with significant positive effects on growth outcomes in each patient cohort.

Results Data from patients with GHD (n = 12 683), TS (n = 1307), NS (n = 203), and PWS (n = 102) were analyzed. HSDS increased over time during GH treatment in all cohorts. Factors with significant positive effects on ΔHSDS were younger age at GH initiation and lower HSDS at baseline (all cohorts) and higher GH dose (GHD and TS only); sex had no effect in any cohort. The modeling analysis showed that ΔHSDS was greatest in year 1 and attenuated over consecutive years through year 5. Estimated least-squares mean ΔHSDS values at year 5 by cohort were 1.702 (females) and 1.586 (males) in GHD, 1.033 in TS, 1.153 in NS, and 1.392 in PWS.

Conclusion Long-term GH therapy results in large increases in HSDS in patients with GHD, TS, NS, and PWS. Greater gains in HSDS can be obtained with higher GH doses and earlier initiation of treatment.