Sleep-Disordered Breathing Is Associated With Adverse Short- and Long-Term Outcomes in Acute Ischemic Stroke and TIA: A Retrospective Cohort Study From the Bern Sleep-Stroke Registry

BACKGROUND: Sleep-disordered breathing (SDB) is common after ischemic stroke and has been associated with adverse outcomes, yet evidence from large stroke cohorts remains limited. We evaluated the association of SDB severity with all-cause mortality, major adverse cardio- and cerebrovascular events (MACCE), and 3-month functional outcome. METHODS: This retrospective cohort study included consecutive patients with ischemic stroke or transient ischemic attack admitted to Inselspital Bern between 2017 and 2021 who underwent in-hospital respiratory polygraphy. SDB severity was classified according to the apnea-hypopnea index as mild (5–<15 events/h), moderate (15–<30 events/h), or severe (≥30 events/h). Outcomes included all-cause mortality, first postindex MACCE, and modified Rankin Scale scores at 3 months. Multivariable Cox and logistic regression models adjusted for age, sex, body mass index, vascular risk factors, admission National Institutes of Health Stroke Scale, intravenous thrombolysis, and mechanical thrombectomy. RESULTS: Among 1083 patients (mean age, 66.0±14.5 years; 62.6% male), SDB (apnea-hypopnea index ≥5 events/h) was present in 819 patients (75.6%), including mild (29.8%), moderate (22.9%), and severe (22.9%). Median follow-up was 51.1 months (interquartile range, 39.1–67.8) for mortality and 47.7 months (interquartile range, 36.9–65.5) for first postindex MACCE; 178 deaths and 153 of 880 patients experienced a first postindex MACCE. Severe SDB was independently associated with increased all-cause mortality (adjusted hazard ratio, 1.73 [95% CI, 1.04–2.89]). Mild, moderate, and severe SDB were associated with first postindex MACCE (adjusted hazard ratio, 1.78 [95% CI, 1.03–3.06]; 2.20 [95% CI, 1.26–3.84]; and 2.16 [95% CI, 1.23–3.78], respectively; P for trend=0.009). Moderate and severe SDB were associated with unfavorable 3-month functional outcome (adjusted odds ratio, 1.74 [95% CI, 1.01–3.04] and 2.48 [95% CI, 1.45–4.31], respectively; P for trend <0.001). CONCLUSIONS: Severe SDB was independently associated with all-cause mortality, whereas SDB severity was associated with first postindex MACCE and unfavorable 3-month functional outcome. Acute-phase SDB assessment may improve prognostic risk stratification.