Association of Black Race With Early Recurrence After Minor Ischemic Stroke or Transient Ischemic Attack: Secondary Analysis of the POINT Randomized Clinical Trial

Abstract

Importance: Stroke incidence is higher among black than white individuals in the United States. It is unclear whether black individuals have a higher risk of stroke recurrence after a minor ischemic stroke or transient ischemic attack (TIA), a high-risk setting in which focused preventive efforts can be effective.

Objective: To examine the association between black race and early ischemic stroke recurrence.

Design, setting, and participants: This cohort study analyzed data from the Platelet Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial conducted at 269 sites from May 28, 2010, to December 19, 2017. The trial enrolled 4881 adults within 12 hours of onset of a minor ischemic stroke (National Institutes of Health Stroke Scale score, 0-3) or high-risk TIA (ABCD2 score, ≥4). For this analysis, we excluded 598 patients enrolled outside the United States and 239 US patients with missing race/ethnicity data.

Main outcomes and measures: The primary outcome for this analysis was ischemic stroke within 90 days after randomization. Covariates included age, sex, Hispanic ethnicity, study assignment to take clopidogrel vs placebo, index stroke vs TIA, vascular risk factors, statin use, study drug adherence, and index event etiological subtype.

Results: Among 4044 patients included in the analysis, 918 (22.7%) were black. In an adjusted Cox model, black race was associated with a higher risk of recurrence compared with white race (hazard ratio, 1.6; 95% CI, 1.1-2.3). Findings were similar in subgroup analyses and in analyses limited to sites that enrolled black patients.

Conclusions and relevance: Among US participants in the POINT trial, black individuals faced a higher risk of early stroke recurrence after a minor ischemic stroke or TIA. Our findings support research into black-white racial differences in the underlying mechanisms of recurrent stroke. In the meantime, extra effort should be made to ensure that black patients have access to proven secondary prevention measures.

Trial registration: clinicaltrials.gov Identifier: NCT00991029.

Conflict of interest statement

Conflict of Interest Disclosures: Dr Kamel reported serving as coprincipal investigator for the National Institutes of Health (NIH)–funded ARCADIA trial, which receives an in-kind study drug from the BMS-Pfizer Alliance and in-kind study assays from Roche Diagnostics, a steering committee member of Medtronic's Stroke AF trial (uncompensated), an end point adjudication committee member for a trial of empagliflozin for Boehringer-Ingelheim, and an advisory board member for Roivant Sciences on the topic of Factor XI inhibition. Dr Levitan reported grants from Amgen and personal fees from Novartis outside the submitted work. Dr Johnston reported nonfinancial support from Sanofi and grants from the NIH/National Institute of Neurological Disorders and Stroke (NINDS) and AstraZeneca. No other disclosures were reported.

Figures

Figure.. Cumulative Risk of Recurrent Ischemic Stroke Among US Patients in the Platelet-Oriented Inhibition in New Transient Ischemic Attack or Minor Ischemic Stroke Trial, Stratified by Race

Differences between groups were significant by the log-rank test (P = .002).