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

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.

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.

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.

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.