Most therapies for fibromyalgia do not substantially ease pain or improve quality of life, an analysis indicates.
Though the study found evidence supporting the effectiveness of cognitive behavioral therapy (CBT), antidepressants and central nervous system depressants, the effect of most treatments was generally small, and their clinical significance unclear.
The analysis, “Association of Therapies With Reduced Pain and Improved Quality of Life in Patients With Fibromyalgia A Systematic Review and Meta-analysis,” was published in the journal JAMA Internal Medicine.
Fibromyalgia is managed through a variety of treatments, from medications (pharmacological) to approaches like exercise and talk therapy (non-pharmacological). Clinical trials are critical for determining whether any given therapy can effectively ease fibromyalgia symptoms, but any single trial will have limitations and design flaws.
A meta-analysis is a statistical technique where researchers analyze combined data from multiple previous studies, potentially providing a more precise estimate of the effect of treatment than any individual study.
Researchers in Brazil and Australia analyzed data from 224 clinical trials with a control group, and a total of 29,962 fibromyalgia patients. These trials assessed 65 different therapies, including both pharmacological and non-pharmacological treatments, used alone or in various combinations.
The researchers calculated these treatments’ effects on pain — measured with a visual analog scale and other instruments — and on quality of life, which was assessed using the fibromyalgia impact questionnaire.
The investigators specifically looked for high-quality evidence concerning the therapies, “which means that the estimated outcomes are unlikely to change with further trials,” they wrote.
In the short term (within three months of beginning treatment), they found high-quality evidence supporting CBT as a way to ease pain. CBT is a kind of talk therapy that focuses on raising a person’s awareness of inaccurate or negative thoughts. No such evidence favored the use of antiemetics — medications against vomiting or nausea — for easing pain in the short term.
Over the medium term — three to 12 months after starting treatment — antidepressants and central nervous system depressants were effective in lowering pain. Evidence also supported antidepressants as improving quality of life.
Antidepressants, as the name suggests, are used to treat depression, while central nervous system depressants are a class of medications that decrease nervous system activity, such as sedatives and tranquilizers.
Although trial data were high-quality in a statistical sense, “our results indicate small effect sizes that may not be clinically important for antidepressants and central nervous system depressants for pain or QOL [quality of life],” the researchers wrote.
Evidence for other therapies, such as exercise, was generally of lower quality.
“Further high-quality trials may increase our certainty with respect to the effectiveness of exercises in fibromyalgia,” the scientists wrote.
No high-quality evidence supported any therapy in the long term, meaning after more than a year. Yet, the team said that assessments of outcomes on this time scale were insufficient — only one trial evaluated pain and quality of life over the long term.
“Clinicians should be aware that current evidence for most of the available therapies for the management of fibromyalgia is limited to small trials of low methodological quality … In addition, the current evidence is lacking for the long-term associations of therapies with outcomes in this chronic health condition,” the investigators concluded.
The scientists also noted that effectiveness is not the only factor to consider when making treatment decisions. “Clinicians and patients should choose therapies by considering other important outcomes in addition to those presented in this review, such as adverse effects, out-of-pocket costs, and patient preferences,” they wrote.