Growth hormone therapy and quality of life in adults and children.

A fundamental goal of growth hormone (GH) treatment for both adults and children is improvement in quality of life (QOL). Assessments of the therapeutic role of GH depend on its effectiveness in meeting this and other goals (including improved metabolic status in adults and improved growth in children) in relation to economic parameters. However, there are difficulties in interpreting data on GH treatment and QOL. These include controversy about appropriate definitions and measures for assessing QOL, disease adaptation, comorbid conditions, and potential patient selection bias. In GH-deficient adults who have completed linear growth, there is considerable evidence that GH exerts effects on body composition, serum lipids, and bone and mineral density. Several controlled trials have also examined the effect of GH treatment on QOL in GH-deficient adults. They generally indicate improvement in QOL with GH treatment, although there are inconsistencies in the data. Caveats include differing outcome measures and instruments, instruments that are not disease specific, variation in characteristics of patient samples and treatment protocols, evidence of a placebo effect, and some inconsistency among results. Open-label trials in adults also suggest improvement in QOL with GH treatment, although interpretation is limited by potential placebo effects and patient self-selection. Studies in children have generally addressed psychological status, and relatively few specifically focus on QOL. In children with classical GH deficiency, it is intuitive that GH treatment will improve QOL, although hard data are lacking. In children with idiopathic short stature, evidence for improved QOL as a result of GH treatment is not well developed. Translating changes in QOL, together with physiological and metabolic benefits, into economic cost-benefit or cost-effectiveness analyses are needed. In doing so, it will be important to consider subgroups of patients who may derive differential benefit from GH treatment. These analyses are central to the development of a framework for research, decision making, and policy for GH treatment.

Effect of growth hormone therapy on height in children with idiopathic short stature: a meta-analysis.

CONTEXT: Use of growth hormone (GH) therapy to promote growth in children with idiopathic short stature is controversial. A fundamental issue underlying the controversy is uncertainty about the magnitude of effectiveness of GH for this condition. OBJECTIVE: To determine the effect of GH on short- and long-term growth in idiopathic short stature. STUDY DESIGN: Systematic review of controlled and uncontrolled studies. DATA SOURCES: MEDLINE (1985-2000), key journals, cross-referencing of bibliographies, abstract booklets, and experts. STUDY SELECTION AND DATA EXTRACTION: We performed a meta-analysis of all studies satisfying the inclusion criteria for idiopathic short stature: initial height below the 10th percentile, normal stimulated GH levels (>10 microg/L), absence of comorbid conditions, no previous GH therapy, treatment with biosynthetic GH, and inclusion of major outcome measures. PRIMARY OUTCOME MEASURES: Growth velocity and height SD score (number of SDs from mean height for age and sex) at baseline and after 1 year to evaluate the short-term effect of GH. Adult height was analyzed to evaluate the long-term effect of GH. DATA SYNTHESIS: Ten controlled trials (434 patients) and 28 uncontrolled trials (655 patients) met the inclusion criteria. While baseline growth velocities were equivalent at baseline, 1-year growth velocity of the GH-treated group significantly exceeded that of controls by 2.86 cm/y. Similarly, in uncontrolled trials, growth velocity increased after 1 year, and height SD score increased from -2.72 at baseline to -2.19. In controlled studies, the adult height of the GH-treated group significantly exceeded controls by 0.84 SD, and in uncontrolled trials the adult height attained after GH treatment (-1.62 SDs) exceeded that predicted at baseline (-2.18 SDs). These results suggest an average gain in adult height of approximately 4 to 6 cm (range, 2.3-8.7 cm) with GH therapy. Given current treatment costs, this corresponds to more than $35 000 per inch (2.54 cm) gained in adult height in idiopathic short stature. CONCLUSIONS: Treatment with GH results in short-term increases in growth for children with idiopathic short stature, and long-term GH can increase adult height. These results are fundamental to decisions about GH use and raise questions about the goals of treatment. Use of GH for idiopathic short stature in clinical practice will depend on its efficacy in promoting growth and the value of this effect to families, physicians, and third-party payers.