Severity and Prevalence of Sleep-Disordered Breathing After Ischemic Stroke

Stroke due to atherosclerosis. Illustration of an arterial blockage (expanded view at upper right) causing a stroke (cerebrovascular accident, CVA). This stroke is due to a build-up of the plaque that forms in atherosclerosis. This blockage causes an interruption (occlusion) of the oxygenated blood supply. This will cause a stroke, where the brain is damaged due to hypoxia (lack of oxygen). The grey area at upper right shows the area of the brain affected by lack of oxygen. This type of stroke is known as an atherosclerotic stroke. Common causes are high blood pressure and arterial disease.
A study was done to determine changes and trends in poststroke sleep-disordered breathing over a 10-year period.

In a large, population-based cohort of participants who have experienced an ischemic stroke, the prevalence of sleep-disordered breathing (SDB) following stroke increased by 15% over a 10-year period, and the mean respiratory event index (REI) increased from 19 hours to 23 hours. These findings were published in the Journal of the American Heart Association.

Researchers sought to evaluate changes in poststroke SDB between 2010 and 2019. They used data from The Brain Attack Surveillance in Corpus Christi (BASIC) project, a stroke surveillance study that was conducted in all acute care hospitals in Nueces County, Texas. Active and passive surveillance was used to identify all cases of stroke among adults aged 45 years or older who were residents of Nueces County. All cases of stroke were validated by stroke-trained physicians. A baseline review, which included the Berlin Questionnaire, was used to evaluate SDB risk with regard to an individual’s prestroke state as soon as possible following presentation of ischemic stroke.

For the current study, all participants in BASIC were offered a home sleep apnea test to determine the presence of SDB following stroke. The evaluation procedures for SDB remained the same throughout the study period. REI was defined as the sum of apneas and hypopneas per hour of recording. SDB was defined as REI of 10 or more hours for optimal sensitivity and specificity of the home sleep apnea device compared with the use of in-laboratory polysomnography.

A total of 2,811 participants completed the Berlin Questionnaire shortly after their presentation with new-onset ischemic stroke (median, 8 days; IQR, 3-40 days). Among the subgroup of 1,489 individuals who consented to using the home sleep apnea test, 1,215 had data available from the test (median, 12 days following stroke; IQR, 6-21 days following stroke).

Results of the study showed that the prevalence of SDB following ischemic stroke increased from 61% to 76%; the mean REI increased from 18.7±15.7 hours to

22.9±18.1 hours. In the unadjusted analysis, a linear association was reported between time and presence of SDB (1.13 times higher odds per year; 95% CI, 1.08-1.19 times higher odds per year). Following adjustment, the rates became 1.13 times higher odds per year (95% CI, 1.07-1.19 times higher odds per year). The time trends did not differ significantly according to sex (P =.24) or ethnicity (P =.36).

A similar linear relationship was reported between time and continuous REI in the unadjusted analysis (mean annual increase, 0.66 per hour; 95% CI, 0.30-1.03 per year). Following adjustment, the mean annual increase was 0.56 per hour (95% CI, 0.20-0.91 per hour). Time trends in REI did not differ significantly according to sex (P =.91) or ethnicity (P =.97).

Further, a statistically significant trend toward a linear relationship between time and high prestroke risk for SDB was reported in the unadjusted analysis (1.03 times higher odds per year; 95% CI, 1.00-1.06 times higher odds per year; P =.08), although this trend was not observed in the adjusted analysis (1.02 times higher odds per year; 95% CI, 0.99-1.05 times higher odds per year; P =.21).

A major limitation of the current study is the lack of validation of the Berlin Questionnaire for evaluating the risk for SDB among patients who have experienced a stroke in reference to their prestroke state, although this has been well validated in the  general population. Additionally, because the study population included mostly participants with low National Institutes of Health Stroke Scale scores, the possibility exists that the findings might lack generalizability.

“These data highlight the need to determine whether SDB treatment improves stroke outcomes,” the researchers wrote.

Disclosure: One of the study authors has declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the author’s disclosures. 


Schütz SG, Lisabeth LD, Gibbs R, et al. Ten-year trends in sleep-disordered breathing after ischemic stroke: 2010 to 2019 data from the BASIC project.J Am Heart Assoc. Published online February 12, 2022. doi: 10.1161/JAHA.121.024169