Sleep architecture in stroke and relation to outcome

The aim of this study was to investigate sleep architecture in stroke patients, and correlate possible disturbances with the topography, severity and outcome of stroke and the presence of sleep-disordered breathing (SDB). In total, 62 acute stroke patients and 16 age- and gender-matched hospitalised controls underwent polysomnographic studies. Sleep architecture was analysed according to the topography of lesion, severity (National Institutes of Health Stroke Scale) and outcome (Barthel Index) of stroke. We found that sleep architecture is disturbed in stroke patients, regardless of SDB. Stroke patients (without SDB) have reductions in total sleep time and sleep efficiency, reduced stage II and slow wave sleep, increased wakefulness during sleep and increased sleep latency. Rapid eye movement (REM) sleep is reduced when SDB is also present. REM sleep is relatively preserved in cerebellar strokes, as opposed to other topographies. Sleep stages I and REM are negatively associated with stroke severity, and the latency to REM sleep is positively correlated with a good outcome. Sleep architecture is impaired in stroke patients (with fragmentation, increased wakefulness and reduced slow wave sleep), and this correlates with severity and outcome. Sleep disturbances should be investigated and addressed in these patients. Further studies are needed to confirm these findings and assess the clinical and therapeutic implications.