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.

High prevalence of growth hormone deficiency in severe fibromyalgia syndromes.

CONTEXT: Fibromyalgia (FM) is characterized by widespread pain and fatigue and is considered a syndrome with different pathogenic mechanisms. Controversial data on GH axis disturbances have been published. Some preliminary trials have shown promising effects of GH therapy on tender points and quality of life in FM. AIM: The aim was to study the patterns of GH secretion/sensitivity in a cohort of severe FM patients. SETTING: The study was conducted in five tertiary hospitals. METHODS: A total of 493 FM women (1990 American College of Rheumatology criteria) recruited from five centers, having more than 16 tender points, Fibromyalgia Impact Questionnaire scores above 75, more than 1 yr of stable medication (serotonin reuptake inhibitors, amitriptyline, and opioids), and body mass index below 35 kg/m(2) underwent baseline IGF-I/GH determinations; an insulin tolerance test (ITT) and a modified IGF-I generation test were performed in those cases showing IGF-I of 150 microg/liter or less. RESULTS: A total of 169 of the 493 patients (34.2%) showed IGF-I of 150 microg/liter or less. Mean peak GH during ITT was 13.3 +/- 9.9 ng/ml in 127 patients in which the test was performed. In 22 of 127 (17.3%), ITT peak GH was 5 microg/ml or less, and in eight of them (6.3%), the peak GH was 3 ng/ml or less. Mean baseline GH (n = 127) was 1.47 +/- 2.58 ng/dl, and eight of 120 (6.8%) showed an insufficient IGF-I response (<50% over baseline) to the IGF-I generation test. CONCLUSION: FM patients show a high prevalence of GH axis dysfunction. A significant number of patients show biochemical patterns of GH deficiency as well as some degree of GH resistance and might be potential candidates for substitution treatment.