Noonan syndrome and Turner syndrome patients respond similarly to 4 years’ growth-hormone therapy: longitudinal analysis of growth-hormone-naïve patients enrolled in the NordiNet® International Outcome Study and the ANSWER Program

Abstract

BackgroundTurner syndrome (TS) and Noonan syndrome (NS) are distinct syndromes associated with short stature and other similar phenotypic features. We compared the responses to growth hormone (GH) therapy of TS and NS patients enrolled in the NordiNet® International Outcome Study (IOS) or the American Norditropin Studies: Web-Enabled Research (ANSWER) Program, which collect information on GH therapy in clinical practice.MethodsRepeated-measures regression analysis was performed on change in height standard deviation score (HSDS) and target-height-corrected HSDS, based on national normal references and treatment-naïve disease-specific references. Models were adjusted for baseline age and HSDS, and average GH dose. The study population was paediatric patients with TS and NS in the NordiNet® IOS and ANSWER Program. Longitudinal growth responses over 4 years were evaluated.ResultsIn 30 NS patients (24 males; baseline age 8.39 ± 3.45 years) and 294 TS patients (7.81 ± 3.22 years), 4-year adjusted ΔHSDS were +1.14 ± 0.13 and +1.03 ± 0.04, respectively (national references). Based on untreated, disease-specific references, 4-year adjusted ΔHSDS for NS and TS were +1.48 ± 0.10 and +1.79 ± 0.04. The analyses showed a significant increase in HSDS over time for both NS and TS (P < 0.0001). ΔHSDS in NS was higher with younger baseline age; ΔHSDS in TS was higher for patients with younger baseline age and higher GH dose.ConclusionsNS and TS patients responded well and similarly over 4 years of GH treatment.Electronic supplementary materialThe online version of this article (doi:10.1186/s13633-015-0015-1) contains supplementary material, which is available to authorized users.

Early growth hormone treatment start in childhood growth hormone deficiency improves near adult height: analysis from NordiNet® International Outcome Study

“…A subsequent publication from the multinational KIGS data reported that 89% of GH-treated patients with isolated GHD reached a NAH within their genetic potential with most of the height gain occurring during the prepubertal years (5). Finally, a recent publication on data from the ANSWER Program, a significant negative association between age at GH treatment start and NAH SDS was observed in a cohort of older children with isolated GHD and delayed skeletal maturation (6). …”

“…We therefore consider the present analysis to add weight and further expand on the evidence reported in the existing literature (4, 5, 6, 8, 13). …”

“…A number of studies have reported that NAH or adult height outcomes in GH-treated children with idiopathic GHD are improved when treatment is started early (4, 5, 6, 8, 13). Reiter et al .…”

“…More recently, Ross et al reported that among a cohort of older patients (mean (standard deviation ( s.d. )) age at GH treatment start 14.0 (2.1) years) with delayed skeletal maturation enrolled in the American Norditropin® Studies: Web-Enabled Research (ANSWER) Program, the majority of GH-treated patients, including those with idiopathic GHD, attained an NAH standard deviation score (SDS) within the normal range (6). …”

Evaluation of the results of Turner syndrome patients during the first three years of recombinant human growth hormone therapy

“…The age gap of the girls at the time of growth hormone implementation was significant and ranged from 3 to 14 years. The results of previous studies in other centers indicate a lack of significant influence of the initiation age and duration of rhGH therapy [12][13][14], while others imply an important role of these factors [11]. However, Ping-Yi Hsu et al stress that early initiation of growth hormone therapy allows the induction of maturation at the right time [15].…”