Symptom-related clinical phenotypes in adults with obstructive sleep apnea: a scoping review.

Objective: To systematically map the variables and methods used to identify symptom-related clinical phenotypes in adults with obstructive sleep apnea (OSA), summarize the major phenotypes and their associations with treatment and health outcomes, and provide evidence to inform multidimensional clinical assessment and long-term follow-up in OSA. Methods: This scoping review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). PubMed, Embase, Web of Science, CINAHL, the Cochrane Library, China National Knowledge Infrastructure, Wanfang Data, VIP, and the Chinese Biomedical Literature Database were systematically searched from inception to 27 June 2026. Two reviewers independently screened records and extracted data. Using the symptom classes reported in the original studies as the units of analysis, we synthesized evidence on phenotype-defining variables, identification methods, recurrent symptom patterns across studies, associations with objective disease burden, positive airway pressure (PAP)-related measures, patient-reported outcomes, and long-term clinical outcomes, as well as longitudinal phenotype transitions. Results: Thirty-six study reports were included. Latent class analysis and cluster analysis were the predominant approaches to phenotype identification. Descriptive cross-study synthesis identified three core phenotypes-daytime sleepiness-predominant, disturbed sleep/insomnia-predominant, and minimally symptomatic-and two extended phenotypes: upper airway/respiratory interruption symptom-predominant and mixed-symptom/high symptom burden. Differences across phenotypes were reported in daytime functioning, psychological status, quality of life, PAP prescription or early use, and symptom improvement following treatment. Symptom burden was not consistently aligned with objective disease burden, and some patients transitioned between symptom phenotypes over time. Conclusions: Recurrent symptom-related clinical phenotypes were observed across studies of adults with OSA. Symptom phenotypes may serve as a complementary component of multidimensional clinical assessment and should be interpreted alongside objective respiratory and hypoxic burden, comorbidities, and treatment information. They may also inform the assessment of changes in symptoms and functional status during long-term follow-up. Future research should refine phenotype identification, strengthen external validation across populations, and further examine associations of symptom phenotypes with treatment response and long-term outcomes.