Association of Therapies With Reduced Pain and Improved Quality of Life in Patients With Fibromyalgia: A Systematic Review and Meta-analysis

Abstract

Importance: Fibromyalgia is a chronic condition that results in a significant burden to individuals and society.

Objective: To investigate the effectiveness of therapies for reducing pain and improving quality of life (QOL) in people with fibromyalgia.

Data sources: Searches were performed in the MEDLINE, Cochrane, Embase, AMED, PsycInfo, and PEDro databases without language or date restrictions on December 11, 2018, and updated on July 15, 2020.

Study selection: All published randomized or quasi-randomized clinical trials that investigated therapies for individuals with fibromyalgia were screened for inclusion.

Data extraction and synthesis: Two reviewers independently extracted data and assessed risk of bias using the 0 to 10 PEDro scale. Effect sizes for specific therapies were pooled using random-effects models. The quality of evidence was assessed using the Grading of Recommendations Assessment (GRADE) approach.

Main outcomes and measures: Pain intensity measured by the visual analog scale, numerical rating scales, and other valid instruments and QOL measured by the Fibromyalgia Impact Questionnaire.

Results: A total of 224 trials including 29 962 participants were included. High-quality evidence was found in favor of cognitive behavioral therapy (weighted mean difference [WMD], -0.9; 95% CI, -1.4 to -0.3) for pain in the short term and was found in favor of central nervous system depressants (WMD, -1.2 [95% CI, -1.6 to -0.8]) and antidepressants (WMD, -0.5 [95% CI, -0.7 to -0.4]) for pain in the medium term. There was also high-quality evidence in favor of antidepressants (WMD, -6.8 [95% CI, -8.5 to -5.2]) for QOL in the short term and in favor of central nervous system depressants (WMD, -8.7 [95% CI, -11.3 to -6.0]) and antidepressants (WMD, -3.5 [95% CI, -4.5 to -2.5]) in the medium term. However, these associations were small and did not exceed the minimum clinically important change (2 points on an 11-point scale for pain and 14 points on a 101-point scale for QOL). Evidence for long-term outcomes of interventions was lacking.

Conclusions and relevance: This systematic review and meta-analysis suggests that most of the currently available therapies for the management of fibromyalgia are not supported by high-quality evidence. Some therapies may reduce pain and improve QOL in the short to medium term, although the effect size of the associations might not be clinically important to patients.

Figure 1.. Flow of Studies Through the Review

RCT indicates randomized clinical trial. ^aArticles could be excluded for more than 1 reason.

Figure 2.. Summary of High- and Moderate-Quality Evidence Meta-analysis on Treatment of Pain in Fibromyalgia

A, Short-term outcomes. B, Medium-term outcomes. Dashed line indicates the minimum clinically important difference. CBT indicates cognitive behavioral therapy; CNS, central nervous system; EEG, electroencephalography; GRADE, Grading of Recommendations Assessment; tDCS, transcranial direct current stimulation; TENS, transcutaneous electrical nerve stimulation; and TMS, transcranial magnetic stimulation. ^aDowngraded owing to imprecision: less than 400 participants included in the meta-analysis. ^bDowngraded owing to inconsistency: I² statistic was higher than 50% or pooling was not possible. ^cDowngraded owing to risk of bias: more than 25% of the participants in the meta-analysis were from trials with a high risk of bias (ie, PEDro score <6 of 10). ^dDowngraded owing to publication bias based on visual inspection of funnel plots and using the Egger test adopting an α = 0.1.

Figure 3.. Summary of High- and Moderate-Quality Evidence Meta-analysis on Quality of Life in Fibromyalgia

A, Short-term outcomes. B, Medium-term outcomes. Dashed line indicates the minimum clinically important difference. CBT indicates cognitive behavioral therapy; CNS, central nervous system; GRADE, Grading of Recommendations Assessment; tDCS, transcranial direct current stimulation; and TMS, transcranial magnetic stimulation. ^aDowngraded owing to imprecision: less than 400 participants included in the meta-analysis. ^bDowngraded owing to risk of bias: more than 25% of the participants in the meta-analysis were from trials with a high risk of bias (ie, PEDro score <6 of 10).