A meta-analysis of the efficacy of fibromyalgia treatment according to level of care

INTRODUCTION: The aim of this paper was to compare the efficacy of the treatments for fibromyalgia currently available in both primary care and specialised settings. METHODS: Published reports of randomised controlled trials (RCTs) researching pharmacological and non-pharmacological treatments in patients with fibromyalgia were found in the MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and PsychInfo databases. The most recent electronic search was undertaken in June 2006. RESULTS: We identified a total of 594 articles. Based on titles and abstracts, 102 full articles were retrieved, 33 of which met the inclusion criteria. These RCTs assessed 120 treatment interventions in 7789 patients diagnosed with primary fibromyalgia. Of them, 4505 (57.8%) were included in the primary care group of our study and 3284 (42.2%) in the specialised intervention group. The sample was mostly made up of middle-aged women, who have had fibromyalgia for a mean period of 6 to 10 years. The mean effect size of the efficacy of the 120 treatment interventions in patients with fibromyalgia compared with controls was 0.49 (95% confidence interval [CI] = 0.39 to 0.58; p < 0.001). In the primary care group it was 0.46 (95% CI = 0.33 to 0.58) while in specialised care it was 0.53 (95% CI = 0.38 to 0.69), with no statistical significance in the differences. We analysed the efficacy of treatments by comparing primary and specialised care in the different fibromyalgia groups and there were no significant differences. The variables of the studies that affected the improvements in the efficacy of fibromyalgia treatment were low quality of the studies and a shorter duration of treatment. However, both factors were biased by the heterogeneity of the studies. Other variables that also improved outcome and were not biased by the heterogeneity of the studies, were younger age of the patients and shorter duration of the disorder. On the contrary, gender and type of treatment (pharmacological vs. psychological) did not affect outcome. CONCLUSION: Based on this meta-analysis and despite the heterogeneity of specialised care studies and of the other limitations described in this article, treating fibromyalgia in specialised care offers no clear advantages.