Assessment of Sleep Pattern in Egyptian Elderly with Vascular Dementia

Study Objectives: Growing evidence suggests that sleep disturbances is common in vascular dementia (VaD). The goal of the current study is to assess the disturbance in sleep pattern in patients with VaD, and compare it to healthy normally cognitive elderly individuals. We next studied whether there are meaningful differences in the Subjective sleep assessment: Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI) and sleep measurements by polysomnography (PSG) in VaD patients. Study design: Case control study. Subject and methods: Overnight PSG recordings and self-reported sleep measures were obtained from 20 healthy elderly subjects and 20 VaD patients at the sleep laboratory. Results: This study showed abnormal subjective sleep quality in all patients and revealed that the most common sleep complaints among VaD patients were: excessive daytime sleepiness (EDS), sleep disordered breathing (SDB), insomnia, restless leg syndrome (RLS), periodic limb movements (PLMS) and REM behavioral disordered (RBD) respectively. Moreover, patients spent more time in stage I sleep, but less time in slow wave sleep (SWS) and REM sleep compared to control populations, with delayed REML and less 1st REML. Also, increased sleep fragmentation; wakefulness after sleep onset (WASO) & sleep fragmentation index (SFI), increased arousal index (AI) & PLMS index were detected in VaD patients. Finally, VaD patients had significant high Apnea, Hypopnea and Respiratory Distress Index (RDI) score with high average SpO2 Desaturation. Conclusions: Sleep is significantly impaired in patients with VaD at both the objective and subjective level, which may be used as a diagnostic marker of VaD. SDB is a common feature of VaD and leads to fragmented sleep, increased nocturnal confusion, and excessive daytime sleepiness. Subjective sleep assessment questionnaire (ESS and PSQI) can be used in VaD patients when objective sleep assessment by PSG recordings is difficult to be done. The PSG study of sleep continuity, sleep architecture, and REM sleep may help in the prevention of progression of VaD.