Abstract W P197: Temporal Association between Infective Endocarditis and Stroke
Introduction: Stroke is a frequent complication of infective endocarditis (IE). However, there is uncertainty regarding the temporal association between IE and stroke.
Methods: Using claims data from nonfederal acute care hospitals in California, we identified patients hospitalized for IE between July 1, 2007 and June 30, 2011. We used validated diagnosis codes to identify a primary composite outcome of ischemic or hemorrhagic stroke during discrete 1-month periods in the 6 months before and 6 months after the diagnosis of IE. We then compared the likelihood of stroke in these 1-month periods to the corresponding 1-month periods 2 years prior, which was considered each patient’s baseline risk of stroke. In a secondary analysis, ischemic and hemorrhagic stroke were evaluated separately. Absolute risks and odds ratios (ORs) were calculated using a Mantel-Haenszel estimator for matched data.
Results: Among 17,926 patients with IE, 2,275 strokes occurred within the 12-month period surrounding the diagnosis of IE, compared to 174 strokes during the corresponding period 2 years prior. The risk of stroke was the highest in the one month after diagnosis of IE as compared to the 1-month period 2 years prior (1640 versus 17 strokes). This equaled an absolute risk increase of 9.1% (95% CI 8.6-9.5) and an odds ratio of 96.5 (95% CI 59.6-155.6). Stroke risk was significantly increased from 4 months before to 5 months after the diagnosis of IE. Similarly, there was an increase in ischemic stroke risk from 4 months before to 3 months after IE, and an increase in hemorrhagic stroke risk from 4 months before to 5 months after IE. In all analyses, the increase in risk was highest in the 1 month after IE diagnosis.
Conclusions: Patients with IE have a dramatically increased risk of ischemic and hemorrhagic stroke. The risk of stroke was highest in the one month after IE diagnosis and persisted for several months afterward. Furthermore, stroke risk was elevated beginning 4 months prior to the diagnosis of IE, which may reflect risk factors that can lead to both stroke and IE (e.g., heart valve surgery) or post-stroke factors that may predispose to IE (e.g., post-stroke immunosuppression or use of central venous catheters after stroke).
Author Disclosures: A.E. Merkler: None. S. Chu: None. M.P. Lerario: None. B.B. Navi: Research Grant; Significant; Florence Gould Endowment for Discovery in Stroke. H. Kamel: Research Grant; Significant; Grant K23NS082367 from NIH/NINDS.
- © 2015 by American Heart Association, Inc.