Assessment of the cognitive function in adult Egyptian patients with obstructive sleep apnea using the Montreal Cognitive Assessment: a retrospective large-scale study

Study Objectives: Sleep apnea is a chronic disorder associated with multiple recognized comorbidities. Only a few studies focus on evaluating the cognitive profile in patients diagnosed with sleep apnea. The aim of the study was to assess the cognitive functions in this population using the Montreal Cognitive Assessment. Methods: The study cohort was 1,445 adult patients who were referred for overnight polysomnography, 764 cases and 681 healthy controls. All participants’ clinical data and comorbidities were taken, and they all performed overnight polysomnography and Montreal Cognitive Assessment. Results: A significantly higher proportion (57.5%) of sleep apnea groups were males; 15.7% were illiterate compared to the non-sleep apnea group. Hypertension and diabetes mellitus were significantly more prevalent among studied patients with sleep apnea, and the mean total score for the Montreal Cognitive Assessment scale was significantly lower among those with sleep apnea at P < .001. Those with no sleep apnea showed a significantly higher function in all attributes compared to patients with sleep apnea—namely, language, orientation, abstraction, naming, attention, and recall (P < .05). Conclusions: Logistic regression analysis was conducted to investigate predictors for occurrence of cognitive impairment (Montreal Cognitive Assessment score < 26) among the studied sample (n = 1,445). The overall model was significant at P < .001. Variables that showed significance in univariate analysis were entered in the model. Significant predictors for cognitive impairment were being male, older age, diabetic, hypertensive, and with a lower level of education and having sleep apnea.