ABSTRACT

Study objective To evaluate the association between obstructive sleep apnea (OSA) and cognitive impairment by comparing individuals with continuous positive airway pressure (CPAP)-treated OSA, untreated OSA, and those without OSA.

Methods In this cross-sectional study, participants were divided into 3 groups based on overnight sleep study and CPAP use: (1) OSA–CPAP group, (2) OSA–no treatment group, and (3)non–OSA group. The primary outcome was the prevalence of cognitive impairment among 3 groups measured by Montreal Cognitive Assessment (MoCA) and the secondary outcome was ambulatory blood pressure monitoring (ABPM).

Results A total of 113 participants (male 69.9%, median age: 57.0 years) are enrolled, comprising 50 participants in the OSA–CPAP group, 50 participants in the OSA–no treatment group, and 13 participants in the non–OSA group. The cognitive impairment prevalence was 46.0% in the OSA–CPAP group, 70.0% in the OSA–no treatment group, and 46.0% in the non-OSA groups (p=0.038). Subdomain analysis showed significantly higher scores in memory and visuospatial abilities in the OSA–CPAP and the non–OSA group (p=0.039 and p=0.005). Post-hoc analysis revealed significantly higher MoCA scores and lower prevalence of cognitive impairment in the OSA–CPAP group compared to OSA–no treatment group (p=0.002 and p=0.015). No significant differences in ABPM parameters were observed.

Conclusion CPAP therapy in patients with OSA is associated with better cognitive performance and lower prevalence of cognitive impairment. These findings suggest a potential role for OSA treatment preserving cognitive function, however further longitudinal studies are needed.

BRIEF SUMMARY The relationship between obstructive sleep apnea (OSA) and cognitive impairment remains controversial. Most prior studies relied on retrospective analyses or selected participants using strict inclusion and exclusion criteria, limiting their real-world applicability. In this study, we analyzed data from unselected patients attending a sleep clinic. We found that patients with treated OSA had a similar prevalence of cognitive impairment as those without OSA, and both groups had a lower prevalence than patients with untreated OSA.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

The author(s) received no specific funding for this work.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

NHG Domain Specific Review Board – e-Centralised Online Submission (ECOS) System (Domain Specific Review Board-C: 2023/01017)

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Data Availability

All relevant data are within the manuscript and its Supporting Information files.

ABBREVIATIONSABPMambulatory blood pressure monitoringAHIapnea hypopnea indexCPAPcontinuous positive airway pressureIQRinterquartile rangeMCImild cognitive impairmentMoCAMontreal Cognitive AssessmentOSAObstructive sleep apneaSDstandard deviation