The influence of sleep apnoea syndrome on cognitive functions in patients with cerebral infarction

The aim of the research. To study cognitive functions and their dynamics in acute cerebral infarction in patients with sleep apnoea syndrome. Material and methods. A total of 74 patients with cerebral infarction (CI) and sleep apnoea syndrome (SAS) (the main group) and 40 patients with CI without SAS (the comparison group) were examined. Cognitive functions were assessed using the Montreal Cognitive Assessment (MOCA) scale within the first 72 hours and one month after the onset of CI. SAS was detected through respiratory polygraphy or autonomous polysomnography. The control group included 40 patients without CI or SAS. CPAP therapy was administered to 20 patients of the main group for 7-10 days. Results. In patients of the main group, median MOCA scores were 20 (18; 23) within the first 72 hours after CI onset and 21.5 (19; 25) after one month, which was significantly lower than those in the comparison and the control groups (p<0.05). The most pronounced cognitive impairments in the main group were observed in patients with severe SAS (apnoea-hypopnea index (AHI) ≥30) (p <0.05). For SAS patients, inverse correlations between the MOCA score at the beginning and the end of acute CI, between the AHI and the maximum duration of the apnoea episode, as well as a direct correlation between the MOCA score and the minimum saturation (p<0.05) have been established. The AHI of over 11.6 respiratory events per hour has been revealed to be a prognostic marker of cognitive dysfunction at the end of acute СI (AUC - 81.1% (95% CI (70.3-89.2)). After a month, the patients receiving CPAP therapy did not significantly differ in cognitive impairments from the rest of the patients in the main group (p>0.05). Conclusion. In SAS patients in the acute period of СI, the AHI increase is accompanied by a decrease in the MOCA score. The AHI of over 11.6 respiratory events per hour can be used to identify risk groups of patients with cognitive impairments requiring correction of treatment and rehabilitation procedures.