Infection and risk of ischemic stroke: differences among stroke subtypes.
ABSTRACT Although prior studies have demonstrated that 25% to 35% of stroke patients have had a recent infection, the role of infection as a risk factor remains unclear. Our aim was to characterize the effect of infectious/inflammatory syndromes on stroke risk.
Case-control and crossover analyses of 233 cases and 363 controls aged 21 to 89 years were performed. Cases were patients hospitalized with a first ischemic stroke at a Los Angeles, California, medical center. Controls were outpatients in the hypertension, diabetes, and general medical clinics. All subjects were administered a neurological examination, an infection/inflammation (I/I) examination, and an interview to elicit recent I/I history at baseline (within several days of stroke onset) and again approximately 2 months later. Three physicians classified subjects by the presence or absence of I/I within 1 month of the index dates, based on findings of the I/I examination, the interview report, and laboratory results.
Infections, either total or specific, were not found more frequently in cases than controls. However, patients with a recent respiratory tract infection suffered more often from large-vessel atherothromboembolic or cardioembolic stroke than did patients without infection (48% vs 24%, P=0.07). The age- and sex-adjusted relative risk estimate for these subtypes was 1.75 (95% CI, 0.86 to 3.55). The risk was notably high for those without stroke risk factors: 4.15 (95% CI, 1.22 to 14.1) for normotensives, 2.71 (95% CI, 1.04 to 7.06) for nondiabetics, and 1.74 (95% CI, 0.74 to 4.07) for nonsmokers. Patients with a recent respiratory infection also had a more severe neurological deficit on admission than those without infection (P=0.05).
Our results suggest that respiratory tract infection may act as a trigger and increase the risk of large-vessel and/or cardioembolic ischemic stroke, especially in those without vascular risk factors.
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ABSTRACT: Ischemic strokes account for 87% of all strokes in the US. Patients who suffer an initial ischemic stroke or transient ischemic attack are at risk for recurrent strokes, as well as ischemic events in the coronary and peripheral vasculatures. Lifestyle modifications and pharmacological and surgical interventions are effective in reducing the risk of recurrent events in all stroke patients, and evidence-based guidelines for secondary stroke prevention are available. However, increasing evidence indicates that risk factors may be differentially associated with specific ischemic stroke subtypes. In the future, exploiting these differential associations may facilitate secondary stroke prevention and, therefore, improve patient outcomes.Journal of the neurological sciences 02/2009; 279(1-2):1-8. · 2.32 Impact Factor
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ABSTRACT: Background. Infections increase the risk of ischemic stroke (IS) and may worsen IS prognosis. Adverse effects of in-hospital infections on stroke outcome were also reported. We aimed to study the prevalence of pre- and poststroke infections and their impact on IS outcome. Methods. We analysed clinical data of 2066 IS patients to assess the effect of pre-stroke and post-stroke infections on IS severity, as well as short-term (up to 30 days) and long-term (90 days) outcome. The independent impact of infections on poor outcome (death, death/dependency) was investigated by use of logistic regression analysis. The effect of antibiotic therapy during hospitalization on the outcome was also assessed. Results. Pre-stroke infections independently predicted worse short-term outcome. In-hospital infections were associated with worse short-term and long-term IS prognosis. Antibacterial treatment during hospitalization did not improve patients' outcome. Conclusions. Prevention of infections may improve IS prognosis. The role of antibiotic therapy after IS requires further investigations.Neurology research international. 01/2011; 2011:691348.