Exploring the relationship between stroke lesion characteristics and sleep in chronic stroke survivors

Sleep is often disrupted after stroke. However, little is known about how stroke lesion extent or location influences sleep, particularly at the chronic stage of recovery. In this pragmatic study, we aimed to explore whether lesion characteristics could explain sleep variability in chronic stroke survivors. We analysed previously collected structural brain images (Magnetic Resonance Imaging) from 38 stroke participants (11 female, mean (SD) age 64 (12), mean (SD) time since stroke 95 (66) months) and sleep data (questionnaires (N=38, actigraphy (N=37), and electrophysiology (N=18)) which were collected in their home environment. Neither lesion volume nor lesion overlap with regions of interest (brainstem, basal ganglia, amygdala, hippocampus, thalamus) significantly predicted interindividual variability in subjective or objective sleep measures. However, a data-driven approach revealed clusters of voxels disconnected by the stroke lesions were linked to lower spindle density and amplitude (threshold free cluster enhancement p < 0.050). Overall, these results provide preliminary insights that lesion induced brain disconnection, rather than the extent and overlap of the lesion with grey matter regions, may be more informative when explaining sleep variability. However, larger prospective studies are needed to fully understand the effect of stroke lesions on sleep.