Patient-Surgeon Sex Concordance Affects Coronary Artery Bypass Grafting Outcomes

Evidence suggests that female patients may have superior outcomes with female surgeons. This study evaluated whether coronary artery bypass grafting (CABG) outcomes vary based on patient and surgeon sex.

Medicare beneficiaries undergoing CABG (7/2016-12/2018) were evaluated. Reoperative, concomitant valve or aortic surgery were excluded. Surgeon sex was obtained by National Provider Identifier. Primary outcomes were risk-adjusted 30- and 90-day mortality and mid-term survival stratified by patient and surgeon sex. Regressions were risk-adjusted for patient demographics and comorbidities and included an interaction term for surgeon and patient sex.

There were 131,130 CABG cases by 2,924 surgeons, of whom 7.8% (213) were female and performed 3.7% (4,871) of CABGs. Female surgeons operated on patients with more comorbidities than male surgeons. Risk-adjusted mortality for male and female surgeons was similar at 30-days and 90-days (3.5 vs 3.7 and 5.2 vs 4.9, p>0.05). When stratified by patient sex, there was no difference in adjusted mortality for male patients by surgeon sex (p>0.05). While female patients had lower 30-day mortality with male versus female surgeons (4.1% vs 5.4%, p=0.044), there was no mortality difference at 90-days (5.8% vs 6.1%, p=0.667). Survival curves for female patients crossed at 90-days, and on landmark analysis female patients had better mid-term survival with female surgeons (HR 0.787 [0.623-0.981], p=0.042).

Female surgeons performed CABG on patients with higher comorbidity burden than male surgeons. While female patients had lower 30-day mortality with male surgeons, survival curves crossed at 90-days, after which survival was superior with female surgeons.