Fibromyalgia

Fibromyalgia is a chronic disorder characterized by widespread musculoskeletal pain, fatigue, sleep disturbances, cognitive dysfunction, and heightened sensitivity to pain, often without identifiable structural abnormalities.

Definition

Epidemiology

Prevalence estimated at 2–4% of the general population
More common in females (female-to-male ratio approximately 3:1)
Typically presents in middle adulthood, though it can occur at any age
Frequently underdiagnosed due to nonspecific symptoms
Associated with significant reduction in quality of life and functional status

Etiology

Multifactorial: genetic predisposition, environmental triggers, and central sensitization
Altered central pain processing and neurotransmitter dysregulation (serotonin, norepinephrine, dopamine)
Sleep disturbances contributing to symptom exacerbation
Physical or emotional stress as precipitating factors
Post-infectious triggers in some cases
Comorbid psychiatric disorders (depression, anxiety) may contribute

Pathophysiology

Central sensitization leading to amplified pain perception
Dysfunction in descending inhibitory pain pathways
Neuroendocrine abnormalities, including HPA axis dysregulation
Altered neurotransmitter levels affecting pain modulation, sleep, and mood
Autonomic nervous system dysfunction (orthostatic intolerance, GI dysmotility)
Microtrauma or peripheral nociceptive input may trigger central sensitization
Chronic pain without significant tissue inflammation or damage