Quantifying the Contribution of Risk Factors for Ischemic Stroke in Patients with a History of TIA

Background. Patients with a history of transient ischemic attack (TIA) are known to be at higher risk for a stroke. We sought to investigate predictors of individual risk for an ischemic stroke within 30 days of a TIA. Methods and Results. A retrospective analysis of 57,585 TIA admissions was collected from 155 United States hospitals. Data describing each admission included demographic and clinical data, and information about the admitting hospital. Cerebrovascular disease was the primary readmission reason (19% of readmissions) in the TIA patient population. The prevalence of 30-day ischemic stroke readmissions was 11 per 1,000 TIA admissions; however, 53% of stroke readmissions occurred within one week. Hierarchal regression models suggested that peripheral vascular disease and hypertensive chronic kidney disease were significant individual stroke risk factors, whereas history of myocardial infarction, essential hypertension, and diabetes mellitus was not associated with significant stroke risk. Certified stroke centers were not associated with significantly lower stroke readmission rates. Conclusions. The results suggest that cardiovascular comorbidities confer the most significant risk for an ischemic stroke within 30 days of a TIA. Interestingly, certified stroke centers do not appear to be associated with significantly lower stroke-readmission rates, highlighting the challenges managing this patient population.