Acute infection as a risk factor for ischemic stroke

Prior studies have demonstrated that infections might precipitate ischemic strokes (IS), but the role of infection as a risk factor remains unclear. We conducted a case-control study to investigate this issue. Consecutive patients (n = 182) with acute IS were examined within 48 hours after admission to our center. A history of acute infections within 2 months before the IS was assessed by means of a specially designed questionnaire that was also given to a control group consisting of 194 consecutive patients who were seen in our outpatient clinic and had suffered IS at least 6 months previously. The prevalence of acute infection in the study group was significantly higher (44/182 = 24.2%) than in the control group (19/194 = 9.7%; odds ratio, 2.93; 95% confidence interval, 1.64 to 5.26; P = .0002) and infection occurred mostly within 1 week before the IS (41/44). Neither the severity of the IS nor the type of the infection was significantly different in patients and control subjects. Acute infections of different types constitute a risk factor for IS, particularly within 1 week of the event. However, the severity of the stroke is not related to this factor.