Stroke-Associated Infection Is an Independent Risk Factor for Poor Outcome after Acute Ischemic Stroke: Data from the Netherlands Stroke Survey

Abstract

Background: Infections are a common and serious threat to patients with acute ischemic stroke. The aim of this study was to assess the effect of infection on mortality and functional outcome at discharge and at 1 year. Methods: From a consecutive cohort study in 11 centers, the Netherlands Stroke Survey, we selected 521 patients with ischemic stroke admitted to hospital within 48 h of onset. Stroke-associated infection was defined as infection occurring within 7 days after admission. Poor outcome (modified Rankin score >2) was recorded at discharge and at 1 year. Results: Stroke-associated infection occurred in 78 patients (15%); 39 of these (7.5%) had pneumonia and 23 (4.4%) had urinary tract infection. Overall, 276 patients (53%) had a poor outcome at 1 year. Poor outcome was recorded in 69 patients with stroke-associated infection (88%), and 37 of the 78 patients with stroke-associated infection (47%) had died at 1 year. After adjustment for confounders, stroke-associated infection was associated with poor outcome at discharge [odds ratio (OR) 2.6, 95% confidence interval (CI) 1.0–6.7] and at 1 year (OR 3.8, 95% CI 1.8–8.9). Pneumonia had a stronger association with poor outcome at 1 year (OR 10, 95% CI 2.2–46). Conclusions: This study suggests that stroke-associated infection, in particular pneumonia, is independently associated with poor functional outcome after ischemic stroke.