Signs and symptoms of sleep apnea and acute stroke severity: is sleep apnea neuroprotective?
BACKGROUND
In animal models, brief periods of hypoxemia render the brain tolerant to subsequent ischemic insults. Sleep apnea leads to frequent episodes of nocturnal hypoxemia and may induce ischemic tolerance. Snoring and daytime sleepiness are cardinal symptoms of sleep apnea. We undertook this study to determine differences in stroke severity and early neurologic course in patients at risk for sleep apnea as determined by a sleep questionnaire.


METHODS
Patients admitted with acute ischemic stroke completed the Berlin questionnaire. The Berlin questionnaire examines habitual snoring, daytime sleepiness, presence of hypertension, and body mass index (BMI) and classifies patients into a high or low risk for sleep apnea group. National Institutes of Health Stroke Scale (NIHSS) score was determined on admission and day 5 of hospitalization. Age, sex, cardiovascular risk factors, BMI, and stroke mechanism were determined prospectively.


RESULTS
We enrolled 190 patients with a mean age of 60 years and 53% were men. The Berlin questionnaire classified 103 patients (54%) at high risk for sleep apnea. The median NIHSS score on admission and day 5 of hospitalization did not differ between the two groups after multivariate analysis. Examined separately, we found no effect of snoring, daytime sleepiness, or BMI on acute stroke severity and outcome.


CONCLUSIONS
We found that a large number of patients admitted with acute ischemic stroke were at high risk for having sleep apnea. We were not able to show that a constellation of symptoms and features highly suggestive of sleep apnea influenced stroke severity or early neurologic course after acute ischemic stroke.
Koch
Sebastian
S
Department of Neurology, University of Miami, School of Medicine, FL, USA. skoch@med.miami.edu <skoch@med.miami.edu>
Zuniga
Sylvia
S
Rabinstein
Alejandro A
AA
Romano
Jose G
JG
Nolan
Bruce
B
Chirinos
Julio
J
Forteza
Alejandro
A
D000208:Acute Disease; D000368:Aged; D015992:Body Mass Index; D002545:Brain Ischemia / Q000150:complications* / Q000503:physiopathology; D048909:Diabetes Complications / Q000503:physiopathology; D006970:Disorders of Excessive Somnolence / Q000209:etiology; D050171:Dyslipidemias / Q000150:complications; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications; D020766:Intracranial Embolism / Q000150:complications / Q000503:physiopathology; D019194:Ischemic Preconditioning; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D012306:Risk; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D012913:Snoring / Q000209:etiology; D020521:Stroke / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D011795:Surveys and Questionnaires