Male stroke patients undergo computed tomography angiography, or CTA, at higher rates than women, with no discernible differences in outcomes, according to a new study.

Stroke is one of the leading causes of death and disability in the U.S. Yet patients can face disparities due to a provider’s implicit bias or lack of access to the best imaging technology, experts wrote Monday in the Journal of the American College of Radiology. Scientists sought to better understand how gender, in particular, fuels disparities in stroke care.

Their study sample spanned more than 7,500 acute ischemic stroke episodes, recorded between 2012 to 2021 at a single comprehensive center for addressing such emergencies. The research team uncovered significantly higher CTA rates among men (odds ratio of 1.2), especially those from socioeconomically advantaged groups. CT angiography is key to selecting patients for stroke treatment. Yet, men also saw much lower rates of undergoing intravenous thrombolysis (odds ratio of 0.83), a clot-busting drug administered via IV.

“We found no sex-based disparity for CTA utilization for minority race/ethnicity (Black, Asian, Hispanic), older patients (age 80+), Medicaid or uninsured patients, low household income (<$80K), or delayed hospital arrival ([last known well to arrival] 6+ hours),” Jason J. Wang, PhD, with the Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, and co-authors wrote Aug. 14. “Instead, we observed that white, privately insured, higher income, and middle aged (50-79 year-old) males specifically had significantly higher CTA utilization.”

However, the higher rate of CT angiography was only significantly associated with the years 2015 and 2019, the authors noted. This corresponded to the two years when the American Heart Association updated its guidelines for treating acute ischemic stroke. In 2015, the association advocated for endovascular thrombectomy for the first six hours following a stroke. Then in 2019, AHA experts recommended such removal of the clot or thrombus under image guidance in the six- to 24-hour time window.

Men had similar rates of undergoing endovascular thrombectomy as females, the study found. And there were no notable sex differences in early clinical outcomes, nor relevant clinical or demographic factors to explain the CTA gap.

“This disparate use of CTA between the sexes in our study did not negatively impact acute stroke treatment, with female patients having significantly higher [intravenous thrombolysis] utilization and similar [endovascular thrombectomy] rates,” the authors reported. “Since CTA results are not often used for decision making for IVT, our findings that female patients had lower CTA utilization but higher IVT frequency is not counterintuitive, and again implies that the observed disparity is an overimaging of male patients.”

Read more about the results, including potential limitations and future areas of investigation, at the link below. The study was supported by the Harvey L. Neiman Health Policy Institute.