Prevalence of cognitive impairment among adults with obstructive sleep apnea: a systematic review and meta-analysis

Abstract

Purpose: Cognitive impairment in obstructive sleep apnea (OSA) poses a growing public health challenge. This systematic review and meta-analysis aims to estimate the prevalence of cognitive impairment among adults with OSA. Methods: We systematically searched PubMed, Embase, Cochrane Library, and Web of Science from database inception to February 2, 2025 for studies on cognitive impairment in OSA adults. OSA diagnosis requires formal clinical confirmation through objective testing; cognitive impairment is assessed using validated standardized instruments. Meta-analysis was executed via Stata 17.0, with publication bias assessed by funnel plots and Egger’s test. Results: Across 23 studies involving 33,226 individuals, the pooled prevalence of cognitive impairment among adult OSA patients was 36.92% (95% CI: 26.62–47.23). Subgroup analyses indicated that the prevalence of 32.22% (95% CI: 12.57–55.60) in mild OSA cases, 36.79% (95% CI: 11.13–67.06) in moderate cases, and 44.46% (95% CI: 30.38–58.98) in severe cases; polysomnography (PSG)-based studies reported a higher prevalence at 38.61% (95% CI: 31.94–45.27) than home sleep apnea testing (HSAT) at 26.85% (95% CI: 19.34–34.36). Prevalence varied significantly by cognitive assessment tool: Montreal Cognitive Assessment (MoCA) yielded 42.20% (95% CI: 34.83–49.57), Mini-Mental State Examination (MMSE) 17.51% (95% CI: 14.07–20.94), Clinical Dementia Rating (CDR) 54.24% (95% CI: 40.75–67.28), and Critical Flicker Frequency (CFF) 27.66% (95% CI: 15.62–42.64). The South-East Asia Region exhibited the highest pooled prevalence at 62.32% (95% CI: 56.86–67.78), followed by the Western Pacific Region at 37.70% (95% CI: 28.50-46.91), the Region of the Americas at 34.21% (95% CI: 5.68–62.74), the Eastern Mediterranean Region at 33.25% (95% CI: 29.91–36.71), and the European Region at 24.89% (95% CI: 19.26–30.52); 46.98% (95% CI, 27.86–66.10) in males and 59.24% (95% CI, 53.20-65.29) in females. Conclusion: The high prevalence of cognitive impairment among adults with OSA highlights the need for increased attention from public health departments. Multinational longitudinal studies using standardized protocols are needed to optimize relevant evidence-based management strategies.