Screening for undiagnosed obstructive sleep apnea in patients with acute stroke or TIA

Obstructive sleep apnea (OSA) is a prevalent and potentially modifiable risk factor for stroke but remains underdiagnosed in clinical practice. Simple screening tools such as the STOP-Bang questionnaire and the Epworth Sleepiness Scale (ESS) may facilitate identification of individuals at risk. However, data on pre-stroke OSA-related symptoms and the utility of these screening tools in acute stroke populations remain limited.

In this prospective observational study, 124 patients admitted with acute ischemic stroke or transient ischemic attack (TIA) at St. Olavs Hospital, Norway, between April 2023 and January 2026 were included. Excessive daytime sleepiness and risk of OSA prior to the index event were assessed retrospectively using the ESS and the STOP-Bang questionnaire during hospitalization, with most patients evaluated within the first three days after admission. Additional information about risk factors and stroke etiology was extracted from medical records.

The mean STOP-Bang score was 3.2, and 65.3% of patients were classified as having intermediate or high risk of OSA. The mean ESS score was 6.5, with 13.7% meeting criteria for excessive daytime sleepiness (ESS ≥ 11). In adjusted regression analyses, higher STOP-Bang scores were associated with higher ESS scores (β = 0.67, p = 0.004), and most patients with elevated STOP-Bang scores did not report excessive daytime sleepiness.

A substantial proportion of patients with ischemic stroke or TIA have a previously unrecognized risk of OSA, while excessive daytime sleepiness is relatively uncommon. STOP-Bang and ESS appear to capture different aspects of sleep-disordered breathing and sleep-related symptoms. STOP-Bang identified a larger proportion of patients at risk of OSA, whereas ESS provided complementary information on subjective daytime sleepiness. Routine screening for OSA symptoms may improve identification of modifiable risk factors relevant for stroke prevention.