What is the evidence supporting the diagnosis of fibromyalgia (Fibromyalgia Syndrome)?

From the Guidelines

Fibromyalgia is a legitimate medical condition supported by substantial scientific evidence, including abnormalities in pain processing, neurotransmitter levels, and genetic associations, as documented in the 2017 EULAR revised recommendations for the management of fibromyalgia 1. The evidence for fibromyalgia is multifaceted, including:

• Central sensitization, where patients exhibit heightened pain processing in the central nervous system
• Altered levels of neurotransmitters like substance P and serotonin
• Abnormal pain signal processing visible on functional MRI scans
• Measurable differences in pain thresholds during quantitative sensory testing
• Genetic associations, with several genes identified as risk factors for fibromyalgia
• Characteristic sleep architecture disturbances, particularly in deep sleep phases, as demonstrated by objective sleep studies
• Inflammatory markers and cytokine abnormalities, as revealed by blood tests
• Predictable responses to certain medications, such as duloxetine, pregabalin, and milnacipran, which target the neurological abnormalities present in fibromyalgia The 2017 EULAR recommendations 1 provide a comprehensive framework for the management of fibromyalgia, emphasizing a graduated approach that combines non-pharmacological and pharmacological treatment modalities tailored to the individual patient's needs. Key recommendations include:
• Aerobic and strengthening exercise, with a strong recommendation (100%) based on level Ia evidence 1
• Cognitive behavioral therapies, with a weak recommendation (100%) based on level Ia evidence 1
• Multicomponent therapies, with a weak recommendation (93%) based on level Ia evidence 1
• Pharmacological management, including amitriptyline, duloxetine, milnacipran, tramadol, pregabalin, and cyclobenzaprine, with varying levels of recommendation based on the strength of evidence 1 Overall, the evidence supports the recognition of fibromyalgia as a complex and heterogeneous condition that requires a comprehensive and multidisciplinary approach to management.

From the Research

Overview of Fibromyalgia

• Fibromyalgia is a chronic pain disorder characterized by widespread pain, fatigue, and sleep disturbances 2.
• It is a chronic condition characterized by generalized musculoskeletal pain associated with other symptoms, especially sleep and mood disorders, fatigue, and cognitive dysfunctions 3.
• Fibromyalgia is present in as much as 2% to 8% of the population, is characterized by widespread pain, and is often accompanied by fatigue, memory problems, and sleep disturbances 4.

Diagnosis of Fibromyalgia

• Diagnosis is based on a clinical approach and known diagnostic criteria, while additional methods, such as radiographic, magnetic resonance, or laboratory analyses, can be useful to exclude other conditions 3.
• The Fibromyalgia Rapid Screening Tool is a helpful screening method for patients with diffuse chronic pain 5.
• The American College of Rheumatology criteria or the Analgesic, Anesthetic, and Addiction Clinical Trial Translations Innovations Opportunities and Networks-American Pain Society Pain Taxonomy diagnostic criteria can diagnose fibromyalgia 5.

Treatment of Fibromyalgia

• Treatment recommendations are based on the most recent evidence-based guidelines from the Canadian Pain Society and graded from 1 to 5 based on the level of available evidence 4.
• Numerous treatments are available for managing fibromyalgia that are supported by high-quality evidence, including nonpharmacological therapies (education, exercise, cognitive behavioral therapy) and pharmacological therapies (tricyclics, serotonin norepinephrine reuptake inhibitors, and gabapentinoids) 4.
• Management begins with educating patients to ultimately relieve them of unnecessary testing and provide reassurance, and treatment emphasizes a comprehensive approach, combining nonpharmacological interventions alongside pharmacologic management 6.
• Duloxetine, milnacipran, pregabalin, and amitriptyline are potentially effective medications for fibromyalgia 6, 5.
• Nonsteroidal anti-inflammatory drugs and opioids have not demonstrated benefits for fibromyalgia and have significant limitations 6, 5.

Symptoms and Quality of Life

• Significant improvements in pain, quality of life, and sleep quality were shown by all three drugs (duloxetine, pregabalin, and milnacipran) in a prospective cohort research study 2.
• The most significant benefits were from duloxetine, which dramatically reduced pain and improved sleep and quality of life (p < 0.05) 2.
• A multidisciplinary approach that incorporates nonpharmacologic therapies and medications to address problematic symptoms is most effective in improving pain and function 5.