Background/aims: Sleep disturbances and fatigue are commonly reported by inpatients undergoing rehabilitation following stroke. This study aimed to investigate the influence of sleep quality on motor function following stroke and to determine if salivary biomarkers of stress, inflammation, and neuroplasticity are associated with motor function or fatigue.
Method: Eighteen stroke survivors undergoing inpatient rehabilitation completed this study (mean age 72 ± 10; 67% male). Overnight actigraphy captured total sleep time, sleep efficiency, sleep onset and awakenings. The following morning self-reported sleep patterns (Leeds Sleep Evaluation Questionnaire) and fatigue (Visual Analog Fatigue Scale) were collected, alongside motor strength (dynamometry) and salivary biomarkers of stress (NR3C1), inflammation (C-reactive Protein, CRP), neuroplasticity (brain derived neurotropic factor, BDNF) and melatonin receptor (MTNR1A, MTNR1B).
Results: Participants reported poor sleep quality, frequent awakenings, and difficulties falling asleep following stroke. There was a significant negative relationship between fatigue severity, sleep quality (r=-0.539, p=0.021) and sleep awakenings (r=-0.656, p=0.003). A significant positive relationship was found between grip strength on the non-hemiplegic limb and salivary gene expression of BDNF (r=0.606, p=0.028), as well as a significant negative relationship between grip strength on the hemiplegic side and salivary gene expression of CRP (r=-0.556, p=0.048).
Conclusion: This study demonstrates the importance of considering sleep in stroke rehabilitation to optimise not only participation in rehabilitation but potentially brain recovery. Collecting objective sleep and salivary biomarker measures may enhance monitoring and prediction of fatigue outcomes following stroke.