Objective: Growth hormone (GH) is known to be required for physical well-being. Although it is also widely believed to be important for quality of life (QoL) and psychological health, there is less supportive evidence. The objective of this study was to investigate the psychological effects of discontinuation of GH replacement from adults with severe GH deficiency (GHD).
Design: A double-blind, placebo-controlled trial in which GH replacement therapy was discontinued for 3 months from 12 of 21 GH-deficient adults, where nine continued with GH replacement.
Patients: GH-treated adults (10 men, 11 women), all with severe GHD (peak GH < 7.7 mU/l on provocative testing), mean age 44.9 years (range 25-68 years).
Measurements: Semi-structured interviews were given at baseline and end-point plus questionnaires that included a new hormone-deficiency specific, individualized, QoL questionnaire (HDQoL), the General Well-being Index (GWBI), the Well-being Questionnaire (W-BQ12), the Short-Form 36 health status questionnaire (SF-36), the Nottingham Health Profile (NHP) and the General Health Questionnaire (GHQ).
Results: Three months after baseline the serum total IGF-I of placebo-treated patients fell from normal, age-related levels (mean 26.6 +/- 13.2 nmol/l) to levels indicative of severe GHD (11.6 +/- 6.6 nmol/l) (P<0.001). Psychological symptoms of GH withdrawal, reported in interviews at end-point by placebo-treated patients, included decreased energy, and increased tiredness, pain, irritability and depression. Patients who believed they knew which treatment they had received correctly identified the treatment (GH or placebo) at end-point (chi2=11.25, P<0.01). Significant between-treatment-group differences in change scores were found for SF-36 General Health (P<0.01), W-BQ12 Energy (P<0.01) and HDQoL do physically (P<0.05), indicating reduced general health, reduced energy and greater perceived impact of hormone deficiency on physical capabilities in the placebo-treated group at end-point relative to GH-treated patients.
Conclusion: Withdrawal of GH treatment from adults with severe GH deficiency has detrimental psychological effects.