Dementia risk associated with comorbid obstructive sleep apnea and anxiety/depression: A nationwide retrospective cohort study in Taiwan.

BACKGROUND

This study examined whether comorbid obstructive sleep apnea (OSA) and anxiety/depression increase dementia risk compared with either condition alone or neither.

METHODS

We conducted a retrospective cohort study using Taiwan's National Health Insurance Research Database (2000-2015). Adults with OSA and/or anxiety/depression were identified and grouped into four cohorts. Propensity score matching (1:1) was applied for age, sex, comorbidities, and index date. Dementia incidence was assessed using Cox regression and Kaplan-Meier methods.

RESULTS

Among 12,496 matched participants, dementia occurred in 497 individuals (15.9%) with comorbid OSA and anxiety/depression. Adjusted hazard ratios were 3.45 (95% CI, 2.94-3.97) for the comorbid group, 1.70 (1.52-2.00) for OSA alone, and 1.49 (1.21-1.75) for anxiety/depression alone versus controls. Dementia risk increased with longer OSA duration.

CONCLUSIONS

Comorbid OSA and anxiety/depression confer a synergistic risk for dementia, with earlier onset and faster progression, underscoring the need for integrated risk assessment.