Factors affecting bone age maturation during 3 years of growth hormone treatment in patients with idiopathic growth hormone deficiency and idiopathic short stature: Analysis of data from the LG growth study

Importance of Growth Factors and Bone Maturation Ratio in the Response to Growth Hormone Therapy

OBJECTIVE

The aim was to identify the influence of insulin-like growth factor I (IGF-1), IGF-binding protein-3 (IGFBP-3), and bone age (BA)/chronological age (CA) ratio on the response to GH therapy after 1 and 2 years of treatment and upon reaching final height.

METHODS

Longitudinal, retrospective, observational study of 139 patients treated for idiopathic growth hormone deficiency. Variables examined during follow-up: (1) genetic background; (2) perinatal history; (3) anthropometry; (4) height velocity, BA, BA/CA and height prognosis; (5) analytical results (IGF-1, IGFBP-3). Final response variables: adult height (AH), AH with respect to target height, AH with respect to initial height prognosis, AH with respect to height at the start of treatment, and AH with respect to height at onset of puberty.

RESULTS

Lower pretreatment IGF-1 levels and a greater increase in IGF-1 at the end of treatment imply a better response (r = -0.405, P = .007 and r = 0.274, P = .014, respectively), as does a greater increase in IGFBP-3 after 2 years of treatment and at the end of treatment (r = 0.207, P = .035 and r = 0.259, P = .020, respectively). A lower BA/CA ratio pretreatment and at the onset of puberty results in a better response (r = -0.502, P = .000 and r = -0.548, P = .000, respectively), as does a lower increase in BA and BA/CA ratio after the 1 and 2 years of treatment (r = -0.337, P = .000 and r = -0.332, P = .000, respectively).

CONCLUSION

Low pretreatment IGF-1, a greater BA delay with respect to CA pretreatment and at the onset of puberty, a greater increase in IGFBP-3 after 2 years of treatment, and a lower increase in BA and BA/CA ratio after 1 and 2 years of treatment imply a better long-term response.

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.

Follow-Up Study of Growth Hormone Therapy in Children with Kabuki Syndrome: Two-Year Treatment Results

INTRODUCTION

Kabuki syndrome (KS) is a genetic disorder with characteristic facial dysmorphisms, short stature, hypertension, and obesity later in life. The aim of this study was to evaluate catch-up growth and cardiovascular markers before and during growth hormone (rhGH) treatment in KS children.

METHODS

This prospective study included 18 children whose KS was genetically established. Each KS subject received rhGH for a period of 2 years. Several measurements were performed before and during treatment: anthropometry, glucose metabolism, lipid profile, markers for endothelial function, and low-grade inflammation.

RESULTS

This study found an increase in delta height standard deviation score (SDS) for the whole group of 1.1 SDS after 2 years of rhGH treatment. Baseline metabolic profiles showed no cardiometabolic abnormalities in these children. Although 4 out of 18 children were obese, there were no signs of the metabolic syndrome. During rhGH treatment, serum low-density lipoprotein cholesterol concentrations decreased significantly (2.16-1.91 mmol/L, p = 0.04). Apolipoprotein B100 concentrations also showed a reduction after 24 months of treatment, but the other lipid and (apo)lipoprotein parameters did not change. While other endothelial function markers were stable, only vascular cell-adhesion molecule-1 concentrations increased (1,084-1,161 pg/mL, p < 0.01) during rhGH therapy. Furthermore, BMI and waist circumference improved during treatment. There were no signs of hypertension.

CONCLUSIONS

At baseline and during rhGH therapy, there were no signs of the metabolic syndrome. This is the first study demonstrating that rhGH treatment in KS children is a safe and effective therapy and that it positively influences linear height without exerting adverse effects on a wide array of cardiovascular risk markers.

A Randomized Controlled Phase 3 Study on the Efficacy and Safety of Recombinant Human Growth Hormone in Children With Idiopathic Short Stature

BACKGROUND

To evaluate the safety and efficacy of daily somatropin (Jintropin^®), a recombinant human growth hormone, in prepubertal children with ISS in China.

METHODS

This study was a multicenter, randomized, controlled, open-label, phase 3 study. All subjects were randomized 3:1 to daily somatropin 0.05 mg/kg/day or no treatment for 52 weeks. A total of 481 subjects with a mean baseline age of 5.8 years were enrolled in the study. The primary endpoint was change in (△) height standard deviation score (HT-SDS) for chronological age (CA). Secondary endpoints included △height from baseline; △bone age (BA)/CA; △height velocity (HV) and △insulin-like growth factor 1 (IGF-1 SDS).

RESULTS

△HT-SDS at week 52 was 1.04 ± 0.31 in the treatment group and 0.20 ± 0.33 in the control group (P < 0.001). At week 52, statistical significance was observed in the treatment group compared with control for △height (10.19 ± 1.47 cm vs. 5.85 ± 1.80 cm; P < 0.001), △BA/CA (0.04 ± 0.09 vs. 0.004 ± 0.01; P < 0.001), △HV (5.17 ± 3.70 cm/year vs. 0.75 ± 4.34 cm/year; P < 0.001), and △IGF-1 SDS (2.31 ± 1.20 vs. 0.22 ± 0.98; P < 0.001). The frequencies of treatment-emergent adverse events (TEAEs) were similar for the treatment and the control groups (89.8% vs. 82.4%); most TEAEs were mild to moderate in severity and 23 AEs were considered study-drug related.

CONCLUSIONS

Daily subcutaneous administration of somatropin at 0.05 mg/kg/day for 52 weeks demonstrated improvement in growth outcomes and was well tolerated with a favorable safety profile.

TRIAL REGISTRATION

ClinicalTrials.gov (identifier: NCT03635580). URL: https://clinicaltrials.gov/ct2/show/NCT03635580.

Investigating whether serum IGF-1 and IGFBP-3 levels reflect the height outcome in prepubertal children upon rhGH therapy: LG growth study database

Serum insulin-like growth factor-1 (IGF-I) and IGF binding protein-3 (IGFBP-3) levels can be used to monitor the safety of recombinant human growth hormone (rhGH) therapy. In this study, we evaluated the changes in serum IGF-I and IGFBP-3 levels during rhGH therapy as a marker of height outcome in prepubertal children. Totally, 705 prepubertal children with short stature were enrolled from the LG Growth Study Database. Data for three groups of subjects were obtained as follows: Idiopathic GH deficiency (IGHD; n = 486); idiopathic short stature (n = 66); small for gestational age (n = 153). Serum IGF-I and IGFBP-3 levels at the baseline and after the 1st and 2nd year of rhGH therapy, as well as the Δheight standard deviation score (SDS), were obtained. Δheight SDS after the 1st and 2nd year of rhGH therapy had notably increased compared to that at the baseline for all three groups. IGF-I and IGFBP-3 levels in all three groups were significantly increased compared to those at the baseline (p <0.001). Δheight SDS was positively correlated with ΔIGF-1 SDS after the 1st year of therapy, ΔIGFBP-3 SDS after the 2nd year of therapy in the IGHD group, and ΔIGF-I SDS and ΔIGFBP-3 SDS after the 2nd year of therapy (p < 0.05), regardless of whether the height at the baseline was a covariate. The increase in IGF-I and IGFBP-3 levels during rhGH therapy was related to the growth response in children with IGHD. Therefore, it may be valuable to measure the change in serum IGF-I and IGFBP-3 levels, especially the latter, during rhGH treatment to predict the growth response upon long-term treatment.

The effects of growth hormones on the growth velocities and serum index expressions in short stature children

OBJECTIVE

To study the effect of recombinant human growth hormone (rhGH) treatment on the growth velocities and serum index expressions of short stature children.

METHODS

56 short stature children admitted to our hospital from January 2018 to January 2020 were recruited as the study cohort. All the children were treated with rhGH. After six months of treatment, their serum indicators [ghrelin, Nesfatin-1, bone-specific alkaline phosphate (BAP), insulin-like growth factor 1 (IGF-1)], their growth velocity indicators [body mass index (BMI), height, growth velocity (GV)], their blood lipid levels [triglycerides (TG), total cholesterol (TC), low density lipoprotein (LDL), high and low density lipoprotein (HDL)], their insulin statuses [fasting insulin (FINS), their homeostasis model assessment of insulin resistance (HOMA-IR)], and their thyroid function index [thyroid stimulating hormone (TSH), 3'-triiodothyronine (T3), 4'-triiodothyronine (T4)] level changes before and after the treatment were compared.

RESULTS

(1) After the treatment, the children's serum ghrelin and IGF-1 levels increased in comparison with their pre-treatment levels (P<0.05), and their nesfatin-1 levels decreased (P<0.05). (2) After the treatment, the children's BMI, height, and GV increased in comparison with their pre-treatment levels (P<0.05). (3) After the treatment, the children's TG levels were noticeably higher than they were before the treatment (P<0.05), and the TC and LDL levels were remarkably lower than they were before the treatment (P<0.05). (4) After the treatment, the children's T3 and T4 levels were significantly higher compared to their levels before the treatment (P<0.05).

CONCLUSION

GH can promote the development and growth of short stature children, improve their related serum indicator levels, and does not induce metabolic dysfunction.

Impact of adherence on growth response during the first 2 years of growth hormone treatment

PURPOSE

Adherence to growth hormone (GH) treatment impacts clinical outcomes. The aim of this study is to assess the impact of adherence to rhGH treatment (2 years) on auxological outcomes.

METHODS

Multicentric, retrospective observational study in rhGH-naïve GHD/SGA children treated with Saizen® during ≥2 years. Growth response was assessed by evaluating the change in height standard deviation score (ΔH SDS) and the index of responsiveness (IoR). Adherence was monitored using EasyPod™ Connect device.

RESULTS

A total of 110 patients (3 Spanish centers) were evaluable (GHD n = 76, SGA n = 34). Adherence was 95.6 and 93.9% (year 1, 2). SGA and GHD children showed an increase of 0.6 cm/year and 1.1 cm/year for each 10% adherence modification. Lower adherence was observed in patients with lower pretreatment height velocity (HV) and in patients whose parents had a lower level of education. A positive correlation between index of responsiveness (IoR) during the first and second years with HV SDS during the second year and between IoR2 and adherence (year 1, 2) was observed. The frequency of patients with HV > 1 SD was higher (p = 0.025) among patients with adherence >90%. The best model to predict the height gain(cm) reaching an adjusted R squared of 0.489 involved percentage of adherence, Tanner stage, pretreatment HV, dose of rhGH, and whether the treatment was initiated before or after puberty.

CONCLUSIONS

Adherence during the first 2 years of response was very high >90% and showed a negative association with age, pretreatment HV and treatment duration and a positive correlation with the level of parent education.

Long-term GH Therapy Does Not Advance Skeletal Maturation in Children and Adolescents

Context

There is no consensus on the effect of recombinant human GH (rhGH) therapy on skeletal maturation in children despite the current practice of annual monitoring of skeletal maturation with bone age in children on rhGH therapy.

Aims

To investigate the effects of long-term rhGH therapy on skeletal age in children and explore the accuracy of bone age-predicted adult height (BAPAH) at different ages based on 13 years of longitudinal data.

Methods

A retrospective longitudinal study of 71 subjects aged 2 to 16 years, mean 9.9 ± 3.8 years, treated with rhGH for nonsyndromic short stature for a duration of 2 to 14 years, mean, 5.5 ± 2.6 years. Subjects with syndromic short stature and systemic illnesses such as renal failure were excluded.

Results

Bone age minus chronological age (BA-CA) did not differ significantly between baseline and the end of rhGH therapy (-1.05 ± 1.42 vs -0.69 ± 1.63, P = 0.09). Piecewise regression, however, showed a quantifiable catch-up phenomenon in BA of 1.5 months per year of rhGH therapy in the first 6.5 years (P = 0.017) that plateaued thereafter (P = 0.88). BAPAH overestimated near-adult height in younger subjects but became more accurate in older subjects (P < 0.0001). IGF-I levels correlated significantly with increases in child's height and BA-CA.

Conclusion

Long-term rhGH therapy demonstrated an initial catch-up phenomenon in skeletal maturation in the first 6.5 years that plateaued thereafter with no overall significant advancement in bone age. These findings are reassuring and support strategic, but not the insurance company mandated reflexive annual monitoring of skeletal maturation with bone age in children receiving rhGH therapy.

Association between Insulin-Like Growth Factor-1 and Relative Skeletal Maturation: A Retrospective Cohort Study of Short Children and Adolescents

Objective

Delays in skeletal maturity are related to bone mass and fracture risk in children, but the factors that determine it are unknown. We aimed to identify the association between insulin-like growth factor-1 (IGF-1) and skeletal maturation before and after growth hormone (GH) treatment.

Methods

In this retrospective cohort study, we observed 783 short children and adolescents, 229 of whom received GH therapy. Skeletal maturation was assessed based on the difference between bone age (BA) and chronological age (CA) (noted as BA-CA). Anthropometric data and laboratory values were measured, and BA was evaluated using the Greulich and Pyle method.

Results

The delayed BA group was defined as BA‐CA < −2 SD (n = 457), and the occurrence rate of BA delay was 58.37%. A nonlinear relationship was observed between the IGF-1 standard deviation score (IGF-1 SDS) and BA-CA before and after GH therapy. Before GH therapy, there was a significant positive association between the IGF-1 SDS and BA-CA when the IGF-1 level was greater than -2 SDS (β 0.17, 95% CI 0.08, 027; P < 0.001). However, we did not observe a significant relationship between the IGF-1 SDS and BA-CA when the IGF-1 level was lower than -2 SDS (β 0.07, 95% CI -0.12, 0.26; P = 0.454). After GH therapy, there was a significant positive association between the IGF-1 SDS and BA-CA when the IGF-1 level was lower than 2 SDS (β 0.20, 95% CI 0.12, 028; P < 0.001). However, we did not observe a significant relationship between the IGF-1 SDS and BA-CA when the IGF-1 level was greater than 2 SDS (β -0.03, 95% CI -0.33, 0.27; P = 0.866).

Conclusion

BA is more delayed in short children and adolescents. There is a nonlinear relationship between IGF-1 and BA maturation in short children before and after GH treatment. These findings suggest that a low level of IGF-1 may contribute to BA delay in short children and adolescents.

The use of recombinant human growth hormone in patients with Mucopolysaccharidoses and growth hormone deficiency: a case series

BACKGROUND

The treatment with recombinant human growth hormone in patients affected by Mucopolysaccharidoses (MPS) is considered whenever a concurrent diagnosis of growth hormone deficiency is demonstrated. The short- and long-term effects of recombinant human growth hormone in this selected cohort is still debated, given the natural progression of disease-related skeletal malformations and the paucity of treated patients reported in literature. The presented case series provides detailed information about the response to recombinant growth hormone in MPS patients diagnosed with growth hormone deficiency.

CASES PRESENTATION

The growth patterns of 4 MPS female patients (current age: 11.7-14.3 years) treated with recombinant human growth hormone due to growth hormone deficiency have been retrospectively analyzed. Two patients, diagnosed with MPS IH, had undergone haematopoietic stem cell transplantation at an early age; the remaining two patients were affected by MPS IV and VI and were treated with enzyme replacement therapy. 4/4 patients presented with a progressive growth deceleration before the diagnosis of growth hormone deficiency was confirmed. This trend was initially reverted by a remarkable increase in height velocity after the start of recombinant growth hormone. We recorded an average increase in height velocity z-score of + 4.23 ± 2.9 and + 4.55 ± 0.96 respectively after 6 and 12 months of treatment. After the first 12-24 months, growth showed a deceleration in all the patients. While in a girl with MPS IH recombinant human growth hormone was discontinued due to a lack in clinical efficacy, 3/4 patients grew at a stable pace, tracking the height centile achieved after the cited initial increase in height velocity. Furthermore, mineral bone density assessed via bone densitometry, showed a remarkable increase in the two patients who were tested before and after starting treatment.

CONCLUSIONS

Recombinant human growth hormone appears to have effectively reverted the growth deceleration experienced by MPS patients diagnosed with growth hormone deficiency, at least during the first 12-24 months of treatment.