Risk of Acute Stroke After Hospitalization for Sepsis: A Case-Crossover Study

BACKGROUND AND PURPOSE—Infections have been found to increase the risk of stroke over the short term. We hypothesized that stroke risk would be highest shortly after a sepsis hospitalization, but that the risk would decrease, yet remain up to 1 year after sepsis. METHODS—This case-crossover analysis utilized data obtained from the California State Inpatient Database of the Healthcare Cost and Utilization Project. All stroke admissions were included. Exposure was defined as hospitalization for sepsis or septicemia 180, 90, 30, or 15 days before stroke (risk period) or similar time intervals exactly 1 or 2 years before stroke (control period). Conditional logistic regression was used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) for the association between sepsis/septicemia and ischemic or hemorrhagic stroke. RESULTS—Ischemic (n=37 377) and hemorrhagic (n=12 817) strokes that occurred in 2009 were extracted where 3188 (8.5%) ischemic and 1101 (8.6%) hemorrhagic stroke patients had sepsis. Sepsis within 15 days before the stroke placed patients at the highest risk of ischemic (OR, 28.36; 95% CI, 20.02–40.10) and hemorrhagic stroke (OR, 12.10; 95% CI, 7.54–19.42); however, although the risk decreased, it remained elevated 181 to 365 days after sepsis for ischemic (OR, 2.59; 95% CI, 2.20–3.06) and hemorrhagic (OR, 3.92; 95% CI 3.29–4.69) strokes. There was an interaction with age (P=0.0006); risk of developing an ischemic stroke within 180 days of hospitalization for sepsis increased 18% with each 10-year decrease in age. CONCLUSIONS—Risk of stroke is high after sepsis, and this risk persists for up to a year. Younger sepsis patients have a particularly increased risk of stroke after sepsis.