Daytime sleepiness and functional outcomes after neurological insult.

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Publication Date


Publication Title

APTA's 2020 Combined Sections Meeting (CSM)


Purpose/Hypothesis: Sleep impairments are common following stroke or traumatic brain injury (TBI). The consequential daytime sleepiness may influence patients’ participation in rehabilitation and could hinder functional recovery. The purpose of this study was to determine whether daytime sleepiness could prospectively predict changes in function in a sample of patients with stroke or TBI attending an inpatient rehabilitation facility (IRF). We hypothesized that daytime sleepiness would result in poorer cognitive and motor functional outcomes.

Number of Subjects: Thirty-seven patients (mean age 64.3±17.7 years; n=22 male) admitted to an IRF for stroke or TBI completed the study.

Materials and Methods: Daytime sleepiness was assessed shortly after admission to an IRF via three outcome measures: Karolinska Sleepiness Scale (KSS), fatigue Visual Analog Scale (VAS), and Wits Pictorial Sleepiness Scale (Wits). Functional Independence Measure (FIM) scores at admission and discharge from the IRF were used to calculate change in functional mobility and cognitive independence. Descriptive statistics and simple linear regression analyses were calculated using SPSS version 24.

Results: Regression models were statistically significant for the Wits, where Wits scores predicted changes in functional mobility (F=4.26, p=0.047, β=-0.33, R2=0.11) and cognitive independence (F=4.33, p=0.045, β=-0.34, R2=0.11). Conversely, the KSS and VAS did not predict changes in functional mobility or cognitive independence (p>0.05).

Conclusions: Ratings of greater sleepiness on the Wits near admission to an IRF prospectively predicted poorer functional outcomes at discharge from the IRF. Of interest, the KSS and VAS did not predict changes in outcomes, potentially connected to their greater complexity for patients with acquired brain injury, as the KSS involves narrative descriptions and the VAS involves ratings of subjective intensity. Conversely, the Wits is a simple pictorial scale.

Clinical Relevance: Study findings indicate that greater sleepiness on the Wits predicted poorer function, suggesting that clinicians may consider patients’ sleepiness to predict prognoses. Specifically, a simple pictorial scale, such as the Wits, may assist with predicting functional outcomes, instead of more cognitively challenging scales, such as the KSS or VAS, in patients with acute stroke or TBI.

Clinical Institute

Neurosciences (Brain & Spine)