Assessing Sleep in Primary Brain Tumor Patients using Smart Wearables and Patient-Reported Data: Feasibility and Interim Analysis of an Observational Study

Abstract Background Sleep-wake disturbances are common and disabling in primary brain tumor (PBT) patients but studies exploring longitudinal data are limited. This study investigates the feasibility and relationship between longitudinal patient-reported outcomes (PROs) and physiologic data collected via smart wearables. Methods Fifty-four PBT patients ≥18 years wore Fitbit smart-wearable devices for 4 weeks, which captured physiologic sleep measures (e.g., total sleep time, wake after sleep onset (WASO)). They completed PROs (Sleep Hygiene Index, PROMIS Sleep-Related Impairment (SRI) and Sleep Disturbance (SD), Morningness-Eveningness Questionnaire (MEQ)) at baseline and 4 weeks. Smart wearable use feasibility (enrollment/attrition, data missingness), clinical characteristics, test consistency, PROs severity, and relationships between PROs and physiologic sleep measures were assessed. Results The majority (72%) wore their Fitbit for the entire study duration with 89% missing <3 days, no participant withdrawals, and 100% PRO completion. PROMIS SRI/SD and MEQ were all consistent/reliable (Cronbach’s alpha 0.74-0.92). Chronotype breakdown showed 39% morning, 56% intermediate, and only 6% evening types. Moderate-severe SD & SRI were reported in 13% and 17% at baseline, and with significant improvement in SD at 4 weeks (p=0.014). Fitbit-recorded measures showed a correlation at week 4 between WASO and SD (r=0.35, p=0.009) but not with SRI (r=0.24, p=0.08). Conclusions Collecting sleep data with Fitbits is feasible, PROs are consistent/reliable, >10% of participants had SD and SRI that improved with smart wearable use, and SD was associated with WASO. The skewed chronotype distribution, risk and impact of sleep fragmentation mechanisms warrant further investigation.