Association between sleep duration and cognitive function and emotional disorders in middle‐aged and elderly patients with cerebral small vessel disease

Abstract Objectives To investigate the association between the sleep duration with cognitive impairment in middle‐aged and elderly patients with cerebral small vessel disease (CSVD). Methods This cross‐sectional study enrolled hospitalized patients aged ≥55 years diagnosed with CSVD between November 2021 and August 2023. Comprehensive neuropsychological assessments were conducted using seven standardized measures: the mini‐mental state examination (MMSE), clock drawing test (CDT), verbal fluency test (VFT), auditory verbal learning test (AVLT), digit span test (DST), self‐rating anxiety scale (SAS), and self‐rating depression scale, along with objective sleep monitoring using a portable sleep monitoring device. Participants were stratified into three sleep duration groups based on self‐reported nocturnal sleep: short (≤6 h; n = 86), normal (6–9 h; n = 77), and long duration (≥9 h; n = 53). Additionally, they were categorized by daytime napping patterns: no nap ( n = 97), short nap (≤1 h; n = 59), and long nap (>1 h; n = 60). Multivariate linear regression models were used to calculate 95% confidence intervals (95% CIs) for cognitive impairment and emotional disorders. Results The study cohort comprised 216 participants (56.50% male) with a mean age of 66.83 ± 8.16 years. Both short and long sleep durations were associated with poorer MMSE and CDT scores compared to normal sleep duration (short vs. normal sleep: β = −0.201, 95% CI −2.388, −0.360, p < 0.001 for MMSE; β = −0.201, 95% CI −0.480, −0.061, p < 0.05 for CDT; long vs. normal sleep: β = −0.355, 95% CI −3.879, −1.643, p < 0.001 for MMSE; β = −0.329, 95% CI −0.735, −0.273, p < 0.01 for CDT). Compared to short nap duration, both no nap and long nap durations showed worse performance on MMSE, VFT, AVLT, and DST (no nap vs. short nap: MMSE β = −0.304, 95% CI −6.106, −2.078, p < 0.001; VFT β = −0.240, 95% CI −5.808, −1.246, p < 0.01; AVLT β = −0.253, 95% CI −6.136, −1.598, p < 0.01; DST β = −0.209, 95% CI −1.172, −0.160, p < 0.05; long nap vs. short nap: MMSE β = −0.304, 95% CI −6.106, −2.078, p < 0.001; VFT β = −0.200, 95% CI −5.881, −0.625, p < 0.05; AVLT β = −0.188, 95% CI −5.809, −0.580, p < 0.05; DST β = −0.207, 95% CI −1.371, −0.151, p < 0.05). Short nighttime sleep duration was associated with higher SAS scores compared to normal sleep duration ( β = 0.172, 95% CI 0.105, 2.542, p < 0.05), whereas long sleep duration showed no significant association. Conclusion Individuals with nighttime sleep duration of 6–9 h and daytime napping ≤1 h exhibited the best overall cognitive scores. This finding supports the U‐shaped relationship model of “moderate sleep‐cognitive protection.”