Abstract W P200: Wake-up Stroke Is Associated With Greater Diastolic Blood Pressure Variability
Background: Wake-up strokes (WUS) account for approximately 20-30% of strokes. Prior studies have failed to consistently identify specific factors associated with WUS. Some authors have suggested a link to obstructive sleep apnea (OSA) though the pathophysiology of this association remains unknown. We hypothesized that blood pressure variability (BPV), a common finding in OSA, is greater in WUS versus non-WUS patients.
Methods: From a single-center prospective cohort study of ischemic stroke patients admitted between August 2012 and July 2013, we identified WUS vs. non-WUS patients. WUS was defined as stroke symptoms noted first on awakening compared to those that occurred at any other time. BPV was calculated as standard deviation of the mean during the first 24 hours after hospital arrival. We assessed 24-hour BPV, as a continuous measure and in quartiles, in WUS vs. non-WUS patients using univariable and multivariable statistics. A p-value <0.05 was considered significant.
Results: Among 344 patients (65.0+/-16.0 years; 50.9% male; 63.7% white; median NIHSS score 3), 72 were WUS (20.9%). On univariable analyses, demographic, medical history, body mass index, and clinical characteristics were not different between WUS and non-WUS strokes, with the exceptions that WUS patients were older (68.7 vs. 64.0 years; p=0.025), more frequently had prior ischemic stroke (30.6% vs. 16.9%, p=0.010), and no WUS patient received intravenous thrombolysis (p<0.001). Initial systolic (p=0.779) and diastolic BP (p=0.647) were similar between groups. Greater diastolic BPV (10.7 vs. 9.5, p=0.025), however, occurred in WUS patients. In multivariable analysis, prior ischemic stroke (OR 2.03, 95% 1.10-3.73) and highest quartile (>=11.5 mmHg) of diastolic BPV (OR 2.19, 95% CI 1.24-3.85) were independently associated with WUS.
Conclusions: In this prospective study, we observed that diastolic BPV during the first 24 hours is more common in WUS versus non-WUS patients. While the implication of this finding is uncertain, we speculate that increased BPV might trigger WUS. Further research is required.
Author Disclosures: M.D. Lundholm: None. M. Rooney: None. C.E. Corado: None. I.M. Ruff: None. Y. Curran: None. R.A. Bernstein: None. H. Attarian: None. S. Prabhakaran: None.
- © 2015 by American Heart Association, Inc.