Abstract WP176: Prior TIAs Among Patients With Ischemic Stroke In The Greater Cincinnati Northern Kentucky Stroke Study (GCNKSS)

Abstract

Background: TIAs serve as an opportunity to identify and modify risk factors and to prevent future events. Given known epidemiologic differences in strokes by race and sex, our objective was to investigate the rates of prior TIAs among those with incident ischemic stroke (IS) in the GCNKSS. Methods: We included all physician adjudicated, incident IS among adults age ≥20 years in the GCNKSS, a population-based stroke surveillance study in a 5-county region of southern Ohio/ northern Kentucky, in 2005, 2010, and 2015. We calculated the frequency of cases in which a TIA (sudden onset of focal neurologic symptoms lasting ≤ 24 hours) was documented in the 365 days prior to IS. Frequencies and proportions of prior TIA were compared by sex, race, and age, and location at which patients sought care for their TIA was described. Finally, multivariable logistic regression was performed to investigate demographic and clinical predictors of cases in which TIA preceded stroke; covariates were chosen a priori. Results: We included 5310 IS events; mean age was 69.7 (SD 14.8) years, 54.7% were female, and 20.4% were Black. A total of 351 patients (6.6%) had a documented TIA the year preceding their IS. Overall, 42.2% did not seek care for their TIA, 21.6% called 911 and/or came to the ED, 6.0% saw a PCP, and 6.6% sought other care. In 22.5% of cases, location of care was unknown. In adjusted results, older age, female sex, history of hypertension, and CAD were associated with having had a prior TIA, while Black race was not. NIHSS was inversely associated with prior TIA (Table). Prior TIAs were similar between study years. Conclusions: We conservatively estimate that ≥ 6% of patients with first-ever IS had a TIA in the preceding year, though underreporting is likely. Many patients did not report seeking care for the TIA, suggesting missed opportunities for risk factor modification. Further research is needed to understand the implications of sex and race differences in frequencies of prior TIA.