Report of stroke-like symptoms predicts incident cognitive impairment in a stroke-free cohort

Abstract

The present study characterizes the relationship between report of stroke symptoms (SS) or TIA and incident cognitive impairment in the large biracial cohort of the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study. The REGARDS Study is a population-based, biracial, longitudinal cohort study that has enrolled 30,239 participants from the United States. Exclusion of those with baseline cognitive impairment, stroke before enrollment, or incomplete data resulted in a sample size of 23,830. Participants reported SS/TIA on the Questionnaire for Verifying Stroke-free Status at baseline and every 6 months during follow-up. Incident cognitive impairment was detected using the Six-item Screener, which was administered annually. Logistic regression found significant association between report of SS/TIA and subsequent incident cognitive impairment. Among white participants, the odds ratio for incident cognitive impairment was 2.08 (95% confidence interval: 1.81, 2.39) for those reporting at least one SS/TIA compared with those reporting no SS/TIA. Among black participants, the odds ratio was 1.66 (95% confidence interval: 1.45, 1.89) using the same modeling. The magnitude of impact was largest among those with fewer traditional stroke risk factors, particularly among white participants. Report of SS/TIA showed a strong association with incident cognitive impairment and supports the use of the Questionnaire for Verifying Stroke-free Status as a quick, low-cost instrument to screen for people at increased risk of cognitive decline.