Impact of Infection on the Risk of Recurrent Stroke Among Patients With Acute Ischemic Stroke

Abstract

Background and purpose: Infection occurs commonly in patients with acute ischemic stroke. We aimed to investigate the association of infection with short- and long-term risk of recurrent stroke in patients with ischemic stroke.

Methods: Data were derived from ischemic stroke patients in 2 stroke registries: the CSCA (Chinese Stroke Center Alliance) program recorded medical data during hospitalization, and the CNSR-III (Third China National Stroke Registry) recorded the medical data during hospitalization and finished 1-year follow-up. Associations of infection (pneumonia or urinary tract infection) during hospitalization with recurrent stroke in short (during hospitalization) and long term (since 30 days to 1 year after stroke onset) were analyzed. Short-term outcomes were analyzed with logistic models and long-term outcomes with Cox models.

Results: In the CSCA (n=789 596), the incidence of infection during hospitalization reached 9.6%. Patients with infection had a higher risk of stroke recurrence during hospitalization compared with patients without infection (10.4% versus 5.2%; adjusted odds ratio, 1.70 [95% CI, 1.65-1.75]; P<0.0001). In the CNSR-III (n=13 549), the incidence of infection during hospitalization was 6.5%. Infection during hospitalization was significantly associated with short-term risk of recurrent stroke (7.4% versus 3.9%; adjusted odds ratio, 1.40 [95% CI, 1.05-1.86]; P=0.02) but not with long-term risk of recurrent stroke (7.2% versus 5.2%; adjusted hazard ratio, 1.16 [95% CI, 0.88-1.52]; P=0.30).

Conclusions: Infection was an independent risk factor for high risk of early stroke recurrence during hospitalization, but we have not found its sustained effect on long-term recurrent risk in patients with acute ischemic stroke.

Keywords: infection; pneumonia; risk factors; stroke; urinary tract infections.