The incidence of sleep apnea in patients with stroke or transient ischemic attack

Abstract

Disorders of breathing during sleep are defined as cessation or reduction of air flow thorough the upper airway, accompanied by a decrease of oxygen saturation. The results of many studies underline the association between sleep-disordered breathing (SDB) and cerebrovascular disorders. SDB, mostly obstructive sleep apnea syndrome (OSAS), is believed to be an independent risk factor of stroke and is related to poor outcome and increased long-term stroke mortality. The present study evaluated the frequency of SDB in patients with stroke or transient ischemic attack transient ischemic attack. We studied 43 patients (mean age 68.5 +/-11.0), which included 35 males and 8 females, with acute stroke (n=37) and transient ischemic attack (n=6). The assessment included body mass index (BMI), age, cardiovascular risk factors, and localization of stroke. All patients underwent all-night screening for SDB with a portable 8-channel recorder. The apnea/hypopnea index (AHI) for the whole group was 13.3 +/-15.2. AHI <5 was found in 16 patients. Overall, SDB was present in 27 (62.8%) patients with stroke and transient ischemic attack, stratified into those with AHI 5-10, (10 patients), 10-20 (8 patients), and AHI>20 (9 patients). In 15 patients, there was an increase in AHI >or=5 on assuming the supine position. The patients' mean BMI was 27.8 +/-4.7. The analysis of BMI, age, and localization of stroke was not sufficient to identify patients with high risk for SDB. We submit that overnight screening for SDB should be routinely performed in every patient after stroke and transient ischemic attack and it should become a diagnostic tool in neurological departments.