Trajectories of sleep disturbances in the subacute phase after stroke: a longitudinal actigraphy study.

BACKGROUND: Sleep disturbances are common after stroke and may negatively impact recovery and quality of life. However, monitoring sleep parameters over time with objective measures remains underreported. OBJECTIVE: To investigate longitudinal changes in actigraphy-derived sleep parameters from the subacute to later stages after stroke. METHODS: This longitudinal observational study included 18 individuals with stroke who completed seven-day wrist-actigraphy monitoring at baseline and at the most distal valid follow-up assessment obtained more than three months after stroke. The median interval between assessments was 161 days (IQR 102.3-194.0). Time in bed, total sleep time, sleep latency, sleep efficiency, wake after sleep onset (WASO), and number of awakenings were compared using paired t-tests. Mean paired differences, 95% confidence intervals (CIs), and Cohen's d effect sizes were calculated. RESULTS: No statistically significant longitudinal changes were detected. Mean changes were - 0.12 h for time in bed (95% CI - 0.73 to 0.49), - 0.05 h for total sleep time (95% CI - 0.59 to 0.50), - 7.93 min for sleep latency (95% CI - 19.55 to 3.69), - 0.36% points for sleep efficiency (95% CI - 4.19 to 3.48), 3.63 min for WASO (95% CI - 9.22 to 16.48), and 0.43 for number of awakenings (95% CI - 0.74 to 1.59). Effect sizes were small, and exploratory individual-level analysis showed increased sleep efficiency in 10 participants and decreased sleep efficiency in 8. CONCLUSION: The analysis showed no statistically significant changes in sleep patterns between the subacute phase and the follow-up. While sleep metrics remained outside normal ranges at both time points, the small and heterogeneous sample, along with wide confidence intervals, prevents any definitive conclusions about long-term trends or causes.