Women Less Likely to Undergo CABG Than Men, Despite Inclusion in Guidelines

Oliver K. Jawitz, MD

Despite inclusion in guidelines, new research presented at the Society of Thoracic Surgeons (STS) 57th Annual Meeting suggests women with coronary artery disease were significantly less likely to undergo coronary artery bypass grafting (CABG) than their male counterparts.

An analysis of data from the STS Adult Cardiac Surgery Database, results suggest women were 14-22% less likely to undergo guideline-concordant revascularization and investigators suggest this difference could contribute to disparities in outcomes.

"It is clear that sex disparities exist in all aspects of care for patients with coronary artery disease, including diagnosis, referral for treatment, and now, in surgical approaches to CABG. We must ensure that female patients undergoing CABG are receiving evidence-based, guideline-concordant techniques,” said study presenter Oliver K. Jawitz, MD, of the Department of Surgery at Duke University, in a statement.

With an interest in further evaluating sex-based differences in guideline-recommended treatments for women with coronary artery disease, Jawitz and a team of colleagues from Duke University and Johns Hopkins University designed the current analysis using data from the STS Adult Cardiac Surgery Database, which investigators pointed out is the largest cardiac surgical database in the world. After performing a search for all adult patients who underwent first-time isolated CABG in the US from 2011-2019, investigators identified a cohort of 1,212,487 patients for inclusion in the current analysis.

Investigators used multivariable logistic regression adjusted for procedural anatomy to assess association between the female sex and odds of receiving a left internal mammary artery (LIMA) graft for revascularization of the left anterior descending (LAD) artery, undergoing complete revascularization, and undergoing multi-arterial grafting. Of note, these analyses were adjusted for multiple factors including hospital region and annual CABG volume as well as baseline demographic and clinical characteristics from the 2018 STS CABG risk model.

The 1,212,487-patient cohort had a median age of 66 (58-73) years, 75% were men, and 25% (n=301,309) were female. In unadjusted analyses, female sex was associated with lower rates of revascularization with an IMA (93.9% vs 95.9%, P <.001), bilateral IMA (2.9% vs 5.6%, P <.001) or radial artery (3.2% vs 5.6%, P <.001) graft. Further analysis indicated rates of all three procedure types increased over time, but investigators noted the difference between males and females remained relatively unchanged during the study period.

In adjusted analyses, female sex was associated with lower odds of receiving a LIMA graft (aOR, 0.79; 95% CI, 0.75-0.83; P <.001), undergoing complete revascularization (aOR, 0.86; 95% CI, 0.83-0.90; P <.001), and undergoing multi-arterial grafting (aOR, 0.78; 95% CI, 0.75-0.81; P <.001)

"Now that we have identified specific differences in surgical approaches to CABG between females and males, we must further elucidate how these differences result in disparate outcomes such as increased mortality, readmissions, and complications," Jawitz said. "These findings will help inform the development of sex-specific guidelines for the diagnosis and management of cardiovascular disease."

This study, “Sex Disparities in Coronary Artery Bypass Grafting Techniques: A Society of Thoracic Surgeons Database Analysis,” was presented at the Society of Thoracic Surgeons 57th Annual Meeting.