Obstructive Sleep Apnea as a Modifiable Contributor to Chronic Pain in Rheumatologic Disease: The Potential Role of Continuous Positive Airway Pressure Therapy

Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder marked by recurrent episodes of upper-airway obstruction, leading to intermittent hypoxia, recurrent arousals, and fragmented sleep. It is highly prevalent worldwide and remains underdiagnosed, particularly when symptoms such as fatigue, poor concentration, and nonrestorative sleep overlap with obesity, chronic pain, depression, or inflammatory disease. These diagnostic challenges are clinically relevant in rheumatology, where pain, fatigue, poor sleep, and immune activation frequently coexist. This narrative review examines OSA as a potentially modifiable contributor to chronic pain and fatigue in rheumatologic disease. We synthesize evidence on intermittent hypoxia, oxidative stress, systemic inflammation, cytokine-mediated nociceptor sensitization, impaired endogenous pain inhibition, and central sensitization. Disease-specific evidence is reviewed for rheumatoid arthritis, psoriatic arthritis, systemic lupus erythematosus, axial spondyloarthritis, and fibromyalgia. We also evaluate continuous positive airway pressure (CPAP) therapy, distinguishing established benefits for respiratory events, oxygenation, sleepiness, and sleep-related quality of life from less certain pain-related effects. Current evidence suggests that CPAP may improve inflammatory biomarkers, fatigue, and pain sensitivity in selected populations, but direct rheumatology-specific evidence for pain reduction remains limited. An evidence-informed clinical framework is proposed to guide targeted OSA screening, diagnostic referral, treatment as adjunctive care, and follow-up in patients with persistent pain, fatigue, or nonrestorative sleep despite otherwise having appropriate rheumatologic management. As much of the available evidence is observational or mechanistic, future prospective studies should include standardized OSA testing, rheumatology-relevant pain outcomes, inflammatory biomarkers, disease activity measures, and long-term CPAP adherence.