Sleep regularity index as a novel indicator of sleep disturbance in stroke survivors: a secondary data analysis.

Sleep disturbance is common but often overlooked after stroke. Regular sleep is increasingly recognised as important for overall health, yet little is known about how sleep regularity changes after stroke. This study examined differences in the Sleep Regularity Index (SRI) between stroke survivors and healthy controls using actigraphy data from an existing dataset (~ 1 week per participant). Data were analysed for 162 stroke survivors (mean age 61 ± 14 years, 5 ± 5 years post-stroke, 89 males) and 60 controls (mean age 57 ± 17 years, 32 males). Stroke survivors had significantly lower SRI scores than controls (p = 0.001), indicating less regular sleep. In the stroke group, higher SRI correlated with longer total sleep time (p = 0.003) and better self-reported sleep quality (p = 0.001) but not with other sleep metrics. Lower SRI was associated with worse depressive symptoms (p = 0.006) and lower quality of life (p = 0.001) but not with disability (p = 0.886) or time since stroke (p = 0.646). These findings suggest that sleep regularity is disrupted post-stroke and may influence well-being. Future research should explore interventions to improve sleep regularity and related health outcomes in stroke survivors.