Context: Previous research suggests short sleep duration negatively influences baseline computerized neurocognitive test (CNT) performance. However, previous studies have only utilized subjective and single-night measures of sleep duration. Purpose: The purpose of this study was to examine the clinical utility and influence of habitual, device-measured sleep duration on baseline computerized neurocognitive performance and total concussion symptom severity in college-aged individuals. Methods: This study used a cross-sectional design and included participants aged 18 – 25 years enrolled in university classes (N = 61, mean age 20.30 years). The sleep measures included: habitual, device-measured sleep duration, device-measured single-night sleep duration, subjective, single-night sleep duration, and habitual, subjective sleep duration. Participants provided informed consent, completed a sleep diary, were issued an Actigraph GT9X monitor, and instructed to wear the monitor and complete the morning and evening sections of the sleep diary for 7 continuous days. Participants completed the Immediate Post Concussion Assessment and Cognitive Testing (ImPACT) battery. Hierarchical linear regressions were used to examine the influence of habitual, device-measured sleep duration on baseline ImPACT performance. Statistical significance was set at p ≤ .05. Equivalence testing and Bland-Altman plots were used to determine the level of agreement between 1) device-measured single-night sleep duration and habitual, device-measured sleep duration, and subjective, single-night sleep duration; 2) habitual, device-measured sleep duration and habitual, subjective sleep duration. Results: The average habitual, device-measured total nighttime sleep time was 322.13 minutes (5.37 hours). Habitual, device-measured sleep duration did not influence verbal memory (F2,48 = 0.26, p = .77; R2 = 0.011), visual memory (F2,48 = 0.04, p = .96; R2 = 0.002), visual motor processing speed (F2,48 = 0.41, p = .67; R2 = 0.017), or reaction time (F2,48 = 2.29, p = .11; R2 = 0.087). A significant model was found for total concussion symptom severity (F2,48 = 6.63, p = .003; R2 = 0.216); but habitual, device-measured sleep duration did not significantly contribute to the model (B = -0.002, 95% CI: -0.03, 0.02, β= -.02, p = .86). Subjective, single-night sleep duration significantly overestimated device-measured single-night sleep duration (d ̅ = 151.80; Z = -5.08, p ≤ .001) and habitual, device-measured sleep duration (d ̅ = 158.03; t41 = -12.30, p ≤ .001). Habitual, subjective sleep duration significantly overestimated habitual, device-measured sleep duration (d ̅ = -153.18; t48 = -15.57, p ≤ .001). In addition, no agreement was found between 1) device-measured single-night sleep duration, habitual, device-measured sleep duration and subjective, single-night sleep duration; 2) habitual, device-measured sleep duration and habitual, subjective sleep duration. Conclusion: Habitual, device-measured sleep duration did not influence baseline CNT performance or total concussion symptom severity. Further research should determine ImPACT battery’s sensitivity to habitual sleep and sleep loss. Furthermore, future researchers should investigate how other sleep-related variables, like sleep efficiency, may impact baseline CNT performance. Researchers and clinicians should use caution when using device-derived and subjective measures of sleep duration interchangeably.
Read
