The effects of acupuncture in fibromyalgia: integrative review

Fibromyalgia is a complex health condition that affects millions of people around the world, characterized by chronic widespread musculoskeletal pain, accompanied by debilitating symptoms such as intense fatigue, sleep disturbances, morning stiffness, and cognitive problems. This syndrome, which in Brazil affects about 2.5% of the population, especially women between 35 and 44 years old, may also include manifestations such as depression, anxiety, irritable bowel syndrome, migraines, and temporomandibular dysfunction. Fibromyalgia pain may intensify with factors such as cold, humidity, and emotional stress, creating a cycle that significantly compromises patients' quality of life. The challenge in treating this condition lies in the fact that conventional medications often do not provide adequate symptom relief, leading patients and health professionals to seek complementary therapeutic alternatives.

A Brazilian study published in 2021 investigated the efficacy of acupuncture in the treatment of fibromyalgia through an integrative review of the scientific literature. The main objective of the study was to analyze the available evidence on the use of acupuncture as a non-pharmacological method for pain relief in patients with fibromyalgia. The researchers used a rigorous methodology, performing searches in four important scientific databases — Scopus, PubMed, CINAHL, and Bireme — using the terms "analgesia," "acupuncture," and "fibromyalgia." The search covered publications from January 2009 to December 2019, prioritizing studies in English, Spanish, or Portuguese that specifically investigated the analgesic effects of acupuncture in patients with fibromyalgia. After careful analysis of 194 articles initially identified, the researchers selected seven randomized clinical trials of high methodological quality to compose the final review.

The results of the research revealed promising findings about the benefits of acupuncture in the treatment of fibromyalgia. All seven studies analyzed demonstrated that true acupuncture (verum technique) showed superior results to placebo (sham technique) in reducing pain. The studies investigated samples ranging from 20 to 82 patients receiving true acupuncture, with sessions lasting between 20 and 30 minutes. Even with relatively small samples, statistical analyses revealed that acupuncture provided significant reduction in pain scores, both in the short and long term.

The researchers found that acupuncture works through specific mechanisms in the central nervous system, producing analgesic effect particularly in the thalamus, a brain region crucial in the processing of sensory information. In addition, the treatment stimulates the release of endorphins, natural substances of the body that integrate the pain suppression mechanism. The studies also showed that acupuncture increases, in the short term, the binding potential to endogenous opioid antinociceptive systems and μ-opioid receptors in various brain regions related to pain and sensory processing.

The clinical implications of these findings are significant for both patients and health professionals. Acupuncture demonstrated benefits that extend beyond simple pain relief, including improvement in sleep quality, reduction in depression, and increase in overall well-being. One of the studies revealed that acupuncture was more effective and showed fewer adverse effects compared to medications commonly used in the treatment of fibromyalgia, such as pregabalin and duloxetine, with benefits persisting for up to one year after treatment. The side effects of acupuncture proved minimal, limited mainly to mild discomfort and bruising at the needle insertion sites.

For patients, this represents a safe and effective therapeutic option that can be used alone or in combination with other treatments. For health professionals, acupuncture offers a valuable tool in the management of fibromyalgia, especially considering its relatively low cost compared to traditional pharmacologic treatment and its ease of application in various care settings, including primary care.

Although the results are encouraging, the researchers acknowledge some important limitations in their analysis. The main challenge identified was the relatively small sample size in the studies evaluated, which may limit the generalization of the results to larger populations. In addition, there is a need for standardization of acupuncture protocols, since the studies used different application points, numbers of sessions, and treatment durations. The researchers emphasize that more studies with greater methodological rigor and more significant samples are needed to definitively establish the efficacy of acupuncture compared to placebo.

Another important point is that there are still differences among the studies regarding the placebo control methods used, which may influence the results. Despite these limitations, the research concludes that acupuncture represents a promising therapeutic option for patients with fibromyalgia, offering pain relief, improvement in quality of life, and positive interference with sleep, with the additional advantage of presenting a favorable safety profile and accessible costs.