Growth hormone treatment for sustained pain reduction and improvement in quality of life in severe fibromyalgia

Functional defects in growth hormone (GH) secretion and its efficacy as a complementary treatment have been suggested for fibromyalgia. This study investigated the efficacy and safety of low-dose GH as an add-on therapy in patients with both severe FM and low insulin-like growth factor 1 levels. A total of 120 patients were enrolled in a multicenter, placebo-controlled study for 18 months. They were randomly assigned to receive either 0.006 mg/kg/day of GH subcutaneously (group A, n = 60) or placebo (group B, n = 60) for 6 months (blind phase). The placebo arm was switched to GH treatment from month 6 to month 12 (open phase), and a follow-up period after GH discontinuation was performed until month 18. Standard treatment for fibromyalgia (selective serotonin re-uptake inhibitors, opioids, and amitriptyline) was maintained throughout the study. Number and intensity of tender points, Fibromyalgia Impact Questionnaire (FIQ) with its subscales, and EuroQol 5 dimensions test (EQ5D) with visual analogue scale (VAS) were assessed at different time points. At the end of the study, 53% of group A patients obtained fewer than 11 positive tender points, vs 33% of group B patients (P < .05). 39.1% vs 22.4% reached more than 50% improvement in VAS (P < .05). Group A patients showed significantly improved FIQ scores (P = .01) compared with group B. Although GH discontinuation worsened all scores in both groups during follow-up, impairment in pain perception was less pronounced in the GH-treated group (P = .05). In this largest and longest placebo-controlled trial performed in FM (NCT00933686), addition of GH to the standard treatment is effective in reducing pain, showing sustained action over time. (C) 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.