Influence of continuous positive airway pressure on sleep status, neuropsychological characteristics in patients with stroke combined with obstructive sleep apnea syndrome

Abstract

Objective To investigate the effects of continuous positive airway pressure (CPAP) on sleep status, neuropsychological characteristics in patients with stroke combined with obstructive sleep apnea syndrome (OSAHS). Methods Fifty-four patients hospitalized with stroke in Tianjin Medical University General Hospital from May 2014 to January 2016, who were with snoring and met the OSAHS diagnostic criteria, were randomly divided into CPAP combined with drug treatment group (25 cases) and drug treatment alone group (29 cases). The sleep structure and respiratory parameters were evaluated by polysomnography, and the changes of the patients′ sleep status was assessed by Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI). The changes of neurocognitive function were assessed by Montreal Cognitive Assessment (MoCA), Digital Span Test (DST) and Hopkins Verbal Learning Test-revised (HVLT), and Patient Health Questionnaire-9 (PHQ9) was used to evaluate the depression mood changes. The changes of sleep status, cognitive function and mood in the CPAP combined with drug treatment group were compared before and three months after CPAP combined with drug treatment, and with the drug treatment alone group. Results Because five cases were dropped off, there were 20 patients in the CPAP combined with drug treatment group and 29 patients in the drug treatment alone group who completed the study. After three months of CPAP combined with drug treatment, the respiratory parameters apnea hypopnea index (AHI) in the CPAP combined with drug treatment group (29.32±16.57) was significantly lower than that before treatment (41.66±21.84; t=3.926, P=0.001), and the minimum blood oxygen saturation (LSaO2;82.11%±5.66%) was significantly higher than that before treatment (76.11%±8.90%; t=-5.054, P=0.000). However, the sleep structure parameters did not show statistically significant changes compared with those before treatment. The ESS, PSQI and PHQ9 scores in the CPAP combined with drug treatment group (4.53±3.86, 3.00±2.45, 0.00(0.00, 2.00))were significantly decreased compared with those before treatment (10.58±7.82, 7.53±2.87, 3.00(1.00, 9.00); t=-3.883, P=0.001; t=-6.522, P=0.000; Z=-3.549, P=0.000), whereas MoCA, HVLT (total scores, recall and recognition) and DST 1, 2 scores in the CPAP combined with drug treatment group (23.37±4.75, 22.32±6.90, 7.47±3.82, 7.84±2.59, 5.32±2.81) were increased compared with those before treatment (22.16±4.94, 19.16±7.66, 6.68±3.74, 7.32±2.67, 5.00±3.00; t=-2.773, P=0.013; t=-6.857, P=0.000; t=-2.704, P=0.015; t=-2.249, P=0.037; t=-2.882, P=0.010). The ESS, PSQI and PHQ9 scores were significantly reduced in the CPAP combined with drug treatment group compared with the drug treatment alone group (8.76±6.92, 7.59±5.49, 5.00(2.50, 9.50); t=-2.711, P=0.009; t=-3.941, P=0.000; Z=-4.555, P=0.000), whereas the DST1 score was significantly increased compared with the drug treatment alone group (6.45±1.43; t=2.144, P=0.042). Conclusions Three-month CPAP combined with drugs mainly improved the daytime sleepiness and depression of patients with stroke combined with OSAHS. Cognition especially in attention was significantly improved, and the degree of low ventilation and hypoxia was alleviated, whereas there was no significant change in sleep structure disorder. Key words: Stroke; Sleep apnea, obstructive; Cognition; Depression