Sleep-Disordered Breathing Shortly After Stroke Is Not Associated With Poststroke Fatigue at 3 Months

Objectives: Post-stroke fatigue (PSF) is common and often disabling. Its causes are poorly understood. Sleep-disordered breathing (SDB) is highly prevalent after stroke, and causes fatigue. In a multi-center cohort study, we evaluated whether SDB measured shortly after stroke was associated with PSF at 3-months, and thus whether SDB might represent an intervention target for PSF. Methods: Ischemic stroke (IS) patients within the Brain Attack Surveillance in Corpus Christi (BASIC) project were offered overnight SDB screening with a well-validated device shortly after stroke. The primary exposure was the respiratory event index (REI; apneas plus hypopneas per hour of recording), measured using a home sleep apnea test, the ApneaLink Plus™. The primary outcome was PSF, measured 3-months post-stroke using the SF-36 vitality scale, which has been validated for use among stroke patients and has a minimally important difference of 5 points on a 100-point scale. Associations between REI and 3-month PSF were evaluated using multivariable linear regression adjusting for clinical and sociodemographic factors. Results: A total of 355 IS participants completed baseline SDB screening and 3-month PSF assessments. Participants were 44% female, 60% Mexican American, with median initial NIHSS of 2 (IQR: 1-5). SDB assessments occurred at a median of 11 days (IQR 5-20) from the initial stroke presentation. SDB was common, with a median baseline REI of 17 (IQR 10-28). The mean 3-month SF-36 fatigue score was 55 (SD 26), consistent with a moderate fatigue level. No association between baseline REI and 3-month PSF was observed in unadjusted (β=0.95, 95% CI= -1.16, 3.05) or fully adjusted models (β=0.66, 95% CI= -1.40, 2.73), and the 95% confidence intervals for this association did not include the minimally important difference threshold of 5-points. In the fully adjusted model, age and MA ethnicity were associated with lower fatigue scores. Female sex and current depression treatment were associated with higher fatigue scores. Discussion: SDB in the immediate post-stroke period did not predict PSF at 3-months. Though identification and treatment of post-stroke SDB may be important, these efforts are unlikely to impact PSF.