Comparative evaluation of short-term biomarker response to treatment for growth hormone deficiency in Chinese children with growth hormone deficiency born small for or appropriate for gestational age: a randomized phase IV open-label study

Meta-analysis of metabolic changes in children with idiopathic growth hormone deficiency after recombinant human growth hormone replacement therapy

PURPOSES

We aimed to assess the effects of recombinant human growth hormone (rhGH) replacement therapy on metabolic changes by synthesizing data from clinical trials involving children with idiopathic growth hormone deficiency (IGHD).

METHODS

Two investigators independently completed literature search, quality assessment, and data extraction. Effect-size estimates are expressed as weighted mean difference (WMD) with 95% confidence interval (CI).

RESULTS

A total of 16 clinical trials involving 1319 children were eligible for analysis. Overall analyses showed that total cholesterol was significantly decreased after rhGH replacement therapy (WMD: -0.20 mmol/l; 95% CI: -0.30 to -0.10; p < 0.001), and high-density lipoprotein was significantly increased (WMD: 0.29 mmol/l; 95% CI: 0.24 to 0.33; p < 0.001). Marginal increase was noted for low-density lipoprotein (WMD: -0.22 mmol/l; 95% CI: -0.47 to 0.22; p = 0.092). Subsidiary and meta-regression analyses revealed that length of intervention and sample size were possible causes of heterogeneity. There was a low probability of publication bias.

CONCLUSIONS

Our findings indicate an obviously favorable role of rhGH replacement therapy in lipid metabolism in children with IGHD, and this role might be dependent on length of intervention.

Biomarkers of GH action in children and adults

Growth hormone (GH) and IGF-I levels in serum are used as biomarkers in the diagnosis and management of GH-related disorders but have not been subject to structured validation. Auxological parameters in children and changes in body composition in adults, as well as metabolic parameters and patient related outcomes are used as clinical and surrogate endpoints. New treatment options, such as long acting GH and GH antagonists, require reevaluation of the currently used biochemical biomarkers. This article will review biomarkers, surrogate endpoints and clinical endpoints related to GH treatment in children and adults as well as in acromegaly.

The impact of long-term growth hormone treatment on metabolic parameters in Japanese patients with short stature born small for gestational age

BACKGROUND/AIMS

An examination of the effects of up to 260 weeks of growth hormone (GH) therapy on metabolic parameters in Japanese children born small for gestational age (SGA).

METHODS

Data were analysed from a 156-week extension of a 104-week multicentre, randomised, double-blind, parallel-group trial. Sixty-five children born SGA (age 3-<8 years) received 33 μg/kg/day (n = 31, 64.5% male) or 67 μg/kg/day (n = 34, 58.8% male) GH for 260 weeks. Changes in metabolic parameters - glucose, insulin, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol - were recorded. Alterations in weight, body mass index standard deviation score (BMI SDS) and vital signs were also evaluated.

RESULTS

Over 260 weeks of GH treatment, a positive correlation between Δheight SDS and Δinsulin-like growth factor-I SDS was observed. Insulin and glucose levels were generally unaffected. Favourable changes in lipid profiles were recorded, which were maintained for the study duration. No adverse alterations in weight, BMI SDS or vital signs were noted.

CONCLUSION

Long-term, continuous GH treatment in children born SGA appears to be efficacious, associated with potential benefits for several metabolic parameters and associated with no long-term safety concerns.

Comparison of weight- vs body surface area-based growth hormone dosing for children: implications for response

OBJECTIVE

To compare weight (per kg)- vs body surface area (BSA, per m(2) )-based growth hormone (GH) dosing formats in children and to derive a useful conversion formula between the two formats.

PATIENTS AND DESIGN

Growth hormone doses (>33,000) from 1874 children were obtained from the national Australian database (OZGROW) and used to derive conversion formulae and to confirm the accuracy of a conversion formula based on a weight-only BSA estimate. A further 27,000 doses were used to test the accuracy of all formulae. The best conversion formula was used to compare weight- and surface area-based GH dosing, which included an analysis of first year response (∆SDS height or growth velocity, GV).

MEASUREMENTS

Growth hormone doses in mg/m(2) /wk and mg/kg/wk, dose estimates, residuals, first year ∆SDS, first year GV.

RESULTS

The formula, [Formula: see text] based on a weight-only BSA estimate, provides accurate dose conversion (mean residual, 0·005 mg/kg/week). A constant mg/m(2) /week dose expressed in terms of mg/kg/week declines quickly with increasing body weight to approximately 15 kg after which the decline continues although less dramatically. For Australian patients, despite an increase in mean per m(2) dose with increased starting weight/age, the per kg dose decreased. This was associated with a greater decline in first year GV than estimated if a per kg dose had been maintained.

CONCLUSIONS

Growth hormone doses can be accurately converted between formats. Surface area-based GH dosing is likely to result in a reduced height response as children become heavier when compared with weight-based GH dosing.