Study Objectives: Sleep disordered breathing (SDB) is a frequent comorbidity in stroke patients. SDB is one of the independent risk factors for ischemic stroke. Conversely, stroke may contribute to SDB onset or aggravate premorbid SDB. Multiple mechanisms underlying SDB might be responsible for the development of stroke. The aim of this study was to compare polysomnographic, clinical, and laboratory characteristics of wake-up (WUS) and non-wake-up acute ischemic strokes (NWUS). Methods: We prospectively enrolled 88 patients with acute ischemic stroke. Clinical characteristics of the population were recorded on admission, and blood samples were obtained in the fasting condition following morning. SDB was assessed using standard overnight polysomnography in the acute phase of the stroke. Results: WUS were present in 16 patients (18.2%), and NWUS in 72 patients (81.8%). In WUS compared to NWUS, we observed significantly higher values of apnea-hypopnea index (24.8 vs.
I NTRO DUCTI O NA recent population-based study has shown that wake-up strokes (WUS) comprise 14% of all ischemic strokes. The same study concludes, that WUS do not differ from non-wake up strokes (NWUS) in clinical features, risk factors, or outcome.1 There is a diurnal variation in the onset of stroke. Sleep tends to promote ischemic stroke, and there is a higher frequency of strokes occurring in the morning.2,3 Sleep disordered breathing (SDB) is present in up to 72% of stroke patients and is one of the independent risk factors for stroke. 4,5 However, stroke may also aggravate premorbid SDB or even contribute to SDB onset. 6 Multiple mechanisms might link SDB with the onset of cerebral ischemia during the sleep, including coagulation changes, hemodynamic changes, blood pressure (BP) surges, inflammatory overactivity, increased arterial stiffness, increased sympathetic tone, paradoxical embolization, or the development of cardiac arrhythmias.
7-11Currently, WUS patients are excluded from revascularization therapy; therefore, a thorough search for predictors and risk factors of WUS is desirable. The aim of this study was to compare polysomnographic, clinical, and laboratory characteristics of WUS and NWUS with mild-to-moderate severity.
SCIENTIFIC INVESTIGATIONS
Association of Sleep
M ETHO DSThe study population consists of patients hospitalized in the stroke unit of the 1 st Department of Neurology, Comenius University Bratislava from January 2011 to December 2014 with the BRIEF SUMMARY Current Knowledge/Study Rationale: Currently, wake-up stroke patients are excluded from revascularization therapy, so a precise search for predictors and risk factors of wake-up strokes is desirable. The aim of this study was to compare polysomnographic, clinical, and laboratory characteristics of wake-up strokes and non-wake-up strokes with mild-to-moderate severity. Study Impact: We emphasize the importance of significantly higher frequency of moderate-to-severe sleep apnea syndrome among the wake-up stroke population, as this population is indicated for positive...
