Obstructive sleep apnea and long COVID syndrome: a scoping review of current evidence in adults

Background Obstructive Sleep Apnea (OSA) is a prevalent sleep disorder characterized by intermittent hypoxia and sleep fragmentation, contributing to systemic inflammation and autonomic dysfunction. Long COVID refers to persistent symptoms following acute COVID-19 infection. Emerging evidence suggests an association between OSA and persistent post-COVID-19 symptoms, potentially mediated by overlapping biological pathways; however, the direction and causality of this relationship remain uncertain. Aim This scoping review aimed to examine the current evidence regarding the different associations between OSA and Long COVID in adults, summarize the reported clinical findings, and explore the proposed pathophysiological mechanisms linking OSA and Long COVID. Methods Following PRISMA-ScR guidelines, PubMed, Embase, Scopus, Web of Science, Cochrane Library, Google Scholar, and ClinicalTrials.gov were searched for studies published between 2020 and 2026. Eligible studies included observational studies, clinical trials, and reviews involving adults with OSAand/or Long COVID syndrome. Two independent reviewers screened studies, extracted data, and synthesized findings thematically. Results Of 184 identified records, 11 studies met the inclusion criteria. Evidence suggested different associations between OSA and Long COVID across the included studies. Proposed mechanisms included intermittent hypoxia, systemic inflammation, autonomic dysregulation, sleep fragmentation, and circadian disturbance; however, these mechanisms were not consistently measured across studies. Reported Long COVID manifestations among patients with OSA included fatigue, respiratory impairment, cognitive dysfunction, and cardiovascular complications. Evidence regarding the impact of OSA treatment on Long COVID outcomes was limited. Conclusions Current evidence suggests an association between OSA and Long COVID, although the nature and direction of this association vary across studies. However, the evidence remains limited and heterogeneous. Further longitudinal studies are needed to clarify this relationship and determine whether effective OSA management can improve Long COVID outcomes.