Coronary disease & ACSCohort study
Intraoperative Anemia Mediates Sex Disparity in Operative Mortality After Coronary Artery Bypass Grafting
- Retrospective cohort study
- registry database
- causal mediation analysis
Authors' conclusion
The association of female sex with increased CABG operative mortality is mediated to a large extent by intraoperative anemia.
Study context
- Population
- Patients undergoing isolated primary coronary artery bypass grafting (CABG), STS Adult Cardiac Surgery Database, 2011–2022
- Participants
- 1,434,225 patients
- Exposure
- Women vs men
- Womenn = 344,357
- Outcome
- Operative mortality
Main finding
As reported in the abstract
Adjusted odds ratio
1.36
95% CI 1.30–1.41
P < 0.001
By group
Women vs Men
adjusted OR 1.36 (95% CI 1.30–1.41); P < 0.001
- Attributable risk (AR) of female sex for operative mortality
- 1.21 (95% CI: 1.17-1.24)
- AR after adjusting for nadir intraoperative hematocrit (reduced by 43%)
- 1.12 (95% CI: 1.09-1.16)
- Proportion of increased mortality risk with female sex mediated by intraoperative anemia
- 38.5% (95% CI: 32.3%-44.7%)
Observational data: associations, not effects.
Further findings
Median
| Outcome | Women | Men | standardized mean difference |
|---|---|---|---|
| Nadir intraoperative hematocrit | 22.0% (IQR 20.0%–25.0%) | 27.0% (IQR 24.0%–30.0%) | 97.0% |
Operative mortality vs nadir hematocrit (spline regression)
- Stronger association at hematocrit values <22.0%
- P < 0.001
Original publication
Intraoperative Anemia Mediates Sex Disparity in Operative Mortality After Coronary Artery Bypass Grafting. J Am Coll Cardiol. Published 5 March 2024. doi:10.1016/j.jacc.2023.12.032
Summarised from the published abstract; every number is checked against it