Polysomnographic abnormalities in patients with vascular cognitive impairment-no dementia

Abstract

ObjectivesWe aimed to investigate subjective sleep quality and polysomnographic sleep structure features in patients with vascular cognitive impairment-no dementia (VCIND). MethodsFifty-six patients with VCIND, 48 patients with simple stroke (without cognitive impairment), and 48 control subjects were included. The Pittsburgh Sleep Quality Index (PSQI) and polysomnography (PSG) were used to analyze their sleep characteristics. The Montreal Cognitive Assessment (MoCA) was conducted to assess mental state. ResultsPatients with VCIND had higher PSQI scores compared with control subjects and simple stroke patients (P<.01). PSG revealed that patients with VCIND or stroke were more likely to experience prolonged sleep latency (SL), decreased sleep efficiency (SE), increased arousal, and reduced deep sleep and rapid eye movement (REM) sleep than controls. Patients with VCIND had significantly longer SL, increased periodic leg movements in sleep (PLMS), decreased SE, and increased arousal and sleep fragmentation compared to patients with simple stroke (P<.05). In VCIND patients, a significant positive correlation was found between SE and MoCA scores (r=0.632; P<.001), though PSQI, SL, and arousal index were significantly negatively associated with MoCA scores (r=−0.787, −0.740, −0.772, respectively; P<.001 for all). ConclusionsVCIND patients had different abnormal sleep features, including decreased SE, increased PLMS, and prolonged SL and sleep fragmentation. Abnormal sleep in VCIND may be associated with cognitive impairment.