Efficacy of long-term growth hormone therapy in short children with reduced growth hormone biological activity

The economic burden of pediatric growth hormone deficiency in Italy: a cost of illness study

PURPOSE

Growth hormone deficiency (GHD) is a rare condition with a worldwide prevalence of 1 patient in 4000 to 10,000 live births, placing a significant economic burden on healthcare systems. The aim of this study is to generate evidence on the economic burden of children and adolescents with GHD treated with rhGH and their parents in Italy.

METHODS

A cost of illness analysis, adopting the prevalence approach, has been developed, producing evidence on the total annual cost sustained by the Italian National Health System (NHS) and by the society. The study is based on original data collected from a survey conducted among Italian children and adolescents with GHD and their parents.

RESULTS

143 children/adolescents with GHD and their parents participated to the survey, conducted from May to October 2021. Patients had a mean age of 12.2 years (SD: 3.1) and were mostly males (68.5%). The average direct healthcare cost sustained by the NHS was € 8,497.2 per patient/year; adding the out-of-pocket expenses (co-payments and expenses for private healthcare service), the total expense was € 8,568.6. The indirect costs, assessed with the human capital approach, were € 847.9 per patient/year. The total of direct and indirect cost is € 9,345.1 from the NHS perspective, and € 9,416.5 from a social perspective. The total cost incurred by the Italian NHS for children with GHD (range: 5,708-8,354) was estimated in € 48.5-71.0 million, corresponding to 0.04-0.06% of the total Italian public health expense in the year 2020.

CONCLUSIONS

The total annual cost for GHD children is close to € 10,000, and is mainly due to the cost of rhGH treatment. This cost is almost entirely sustained by the NHS, with negligible out-of-pocket expenses. The economic burden on the Italian NHS for the health care of established GHD children is fourfold higher than the prevalence of the disease in the overall Italian population.

Pediatric growth hormone treatment in Italy: A systematic review of epidemiology, quality of life, treatment adherence, and economic impact

Objectives

This systematic review aims to describe 1) the epidemiology of the diseases indicated for treatment with growth hormone (GH) in Italy; 2) the adherence to the GH treatment in Italy and factors associated with non-adherence; 3) the economic impact of GH treatment in Italy; 4) the quality of life of patients treated with GH and their caregivers in Italy.

Methods

Systematic literature searches were performed in PubMed, Embase and Web of Science from January 2010 to March 2021. Literature selection process, data extraction and quality assessment were performed by two independent reviewers. Study protocol has been registered in PROSPERO (CRD42021240455).

Results

We included 25 studies in the qualitative synthesis. The estimated prevalence of growth hormone deficiency (GHD) was 1/4,000–10,000 in the general population of children; the prevalence of Short Stature HOmeoboX Containing gene deficiency (SHOX-D) was 1/1,000–2,000 in the general population of children; the birth prevalence of Turner syndrome was 1/2,500; the birth prevalence of Prader-Willi syndrome (PWS) was 1/15,000. Treatment adherence was suboptimal, with a range of non-adherent patients of 10–30%. The main reasons for suboptimal adherence were forgetfulness, being away from home, pain/discomfort caused by the injection. Economic studies reported a total cost for a complete multi-year course of GH treatment of almost 100,000 euros. A study showed that drug wastage can amount up to 15% of consumption, and that in some Italian regions there could be a considerable over- or under-prescribing. In general, patients and caregivers considered the GH treatment acceptable. There was a general satisfaction among patients with regard to social and school life and GH treatment outcomes, while there was a certain level of intolerance to GH treatment among adolescents. Studies on PWS patients and their caregivers showed a lower quality of life compared to the general population, and that social stigma persists.

Conclusion

Growth failure conditions with approved GH treatment in Italy constitute a significant burden of disease in clinical, social, and economic terms. GH treatment is generally considered acceptable by patients and caregivers. The total cost of the GH treatment is considerable; there are margins for improving efficiency, by increasing adherence, reducing drug wastage and promoting prescriptive appropriateness.

Comparison of the efficacy and safety of recombinant human growth hormone in treating idiopathic short stature and growth hormone deficiency in children

PURPOSE

The present study aimed to compare the efficacy and safety of recombinant human growth hormone (rhGH) therapy between children with idiopathic short stature (ISS) and growth hormone deficiency (GHD).

METHODS

A total of 150 pediatric patients with ISS and 153 pediatric patients with GHD who received rhGH treatment for more than one year from 2005 to 2016 were enrolled. Growth velocity (GV); height standard deviation (HtSD); insulin-like growth factor-1 standard deviation (IGF-1SD); body mass index (BMI); and the incidence of fasting hyperglycemia, fasting hyperinsulinemia, and hypothyroidism were recorded and compared.

RESULTS

At the beginning of treatment, chronological age, bone age, height, and BMI were not statistically significant between the two groups. rhGH dosage in ISS was significantly higher compared with GHD (P = 0). GV from half a year to three years after rhGH therapy was higher in the GHD group compared with the ISS group, but the differences were not statistically significant (P > 0 .05). HtSD increased in the two groups after rhGH therapy. HtSD at the beginning and after three years of therapy was not different between groups except for after half a year of therapy. HtSD in patients with ISS was significantly higher compared with GHD (P < 0 .05). The incidence of hypothyroidism was significantly higher in the GHD group compared with the ISS group (13.72% vs. 6.0%; P < 0.05). Moreover, the incidence of hyperinsulinemia was significantly higher in the ISS group compared with the GHD group (15.33% vs. 7.84%; P < 0 .05).

CONCLUSIONS

rhGH increases growth in children with ISS and GHD. Fasting insulin and thyroid function were closely monitored for long-term follow up.

Significance of Direct Confirmation of Growth Hormone Insensitivity for the Diagnosis of Primary IGF-I Deficiency

Primary insulin-like growth factor-I (IGF-I) deficiency is a synonym of growth hormone (GH) insensitivity (GHI), however the necessity of direct confirmation of GH resistance by IGF-I generation test (IGF-GT) is discussed. GHI may disturb intrauterine growth, nevertheless short children born small for gestational age (SGA) are treated with GH. We tested the hypothesis that children with appropriate birth size (AGA), height standard deviation score (SDS) <−3.0, GH peak in stimulation tests (stimGH) ≥10.0 µg/L, IGF-I <2.5 centile, and excluded GHI may benefit during GH therapy. The analysis comprised 21 AGA children compared with 6 SGA and 20 GH-deficient ones, with height SDS and IGF-I as in the studied group. All patients were treated with GH up to final height (FH). Height velocity, IGF-I, and IGF binding protein-3 (IGFBP-3) concentrations before and during first year of treatment were assessed. Effectiveness of therapy was better in GHD than in IGF-I deficiency (IGFD), with no significant difference between SGA and AGA groups. All but two AGA children responded well to GH. Pretreatment IGF-I and increase of height velocity (HV) during therapy but not the result of IGF-GT correlated with FH. As most AGA children with apparent severe IGFD benefit during GH therapy, direct confirmation of GHI seems necessary to diagnose true primary IGFD in them.

Efficacy of long-term growth hormone therapy in short non-growth hormone-deficient children

BACKGROUND

In recent years, several studies have been published showing different responses to growth hormone (GH) treatment in idiopathic short stature children. The aim of the present study was to investigate whether non-growth-hormone-deficient (non-GHD) short children could benefit from long-term GH treatment as GHD patients.

METHODS

We enrolled 22 prepubertal children and 22 age- and sex-matched GHD patients, with comparable height, body mass index (BMI), bone age, and insulin-like growth factor 1 (IGF-I) circulating levels. The patients were treated with recombinant human GH (rhGH) and followed until they reach adult height.

RESULTS

During GH treatment, the two groups grew in parallel, reaching the same final height-standard deviation score (SDS) and the same height gain. On the contrary, we found significantly lower IGF-I serum concentrations in non-GHD patients than in GHD ones, at the end of therapy (p=0.0055).

CONCLUSIONS

In our study, the response to GH treatment in short non-GHD patients proved to be similar to that in GHD ones. However, a careful selection of short non-GHD children to be treated with GH would better justify the cost of long-term GH therapy.

Growth hormone variants: a potential avenue for a better diagnostic characterization of growth hormone deficiency in children

Human GH (hGH) is a heterogeneous protein hormone consisting of several isoforms. This heterogeneity is the consequence of multiple hGH genes, mRNA splicing, post-translational modifications, and peripheral metabolism, and it represents one important reason for the disparity among GH assay results from different laboratories. However, other factors are involved: a) interference from endogenous GH binding proteins; b) different specificities of anti- GH (monoclonal and polyclonal) antibodies; c) different matrix effects among the calibrators; d) the use of different calibrators. The measurement of GH levels in response to provocative testing is an essential part of the diagnosis of GH deficiency. For this purpose, an accurate, reproducible and universally valid GH measurement would be highly desirable, but, despite a huge number of efforts in clinical biochemistry, this goal remains elusive.