American scientists conducted a retrospective cohort study and found that, although the rate of serious complications during cardiac and vascular surgery is comparable in men and women, the lives of the latter are less likely to be saved. The study was published in JAMA Surgery.
Statistics show that women have a higher mortality rate than men in high-risk surgeries. This is generally attributed to women's higher perioperative risks, as they are more likely to undergo such procedures at an older age and with more comorbid conditions. However, the question of whether this is due to a higher complication rate or the lesser level of care provided remains unclear.
To understand this, Catherine Wagner of the University of Michigan in Ann Arbor and colleagues analyzed data from more than 863,000 patients (35.2 percent women) who underwent high-risk surgeries under Medicare from October 2015 to February 2020. The procedures included abdominal aortic aneurysm repair, coronary artery bypass grafting, aortic valve replacement, and mitral valve replacement or repair.
The average age at surgery was slightly higher in women than in men (74.8 vs. 73.4 years), as was the average number of comorbid conditions (Elixhauser index ≥ 2 in 86.4% vs. 83.2%). Women were more likely to undergo surgery in larger hospitals and hospitals with a higher volume of surgeries. Complications that prolonged the length of hospital stay to more than the 75th percentile for each procedure were considered serious.
These included myocardial infarction, pulmonary embolism, pneumonia, postoperative bleeding, and surgical site infection. Statistical data processing was performed using logistic regression models adjusted for gender, age, 27 comorbid conditions, year of surgery, indication (emergency or elective), and type of intervention.
After introducing all adjustments, it turned out that the rate of serious complications was comparable in women and men: 14.98 versus 14.37 percent. However, the rate of failure to save lives was significantly higher in women: 10.71 versus 8.58 percent (relative risk (RR) 1.25; p < 0.001). Mortality within 30 days after surgery was also higher in them: 4.22 versus 3.34 percent (RR 1.26; p < 0.001). Moreover, repeat surgeries were performed more often in men. Similar patterns were observed when analyzing individual types of interventions. Thus, despite a similar rate of serious complications, the likelihood of death after high-risk surgeries is higher in women, which may indicate that clinicians are not making enough efforts to save them. Improvements in modern recognition and adequate treatment of complications in women can reduce this difference between patients of different genders, the authors of the study conclude. Previously, American, Austrian, and Swedish researchers demonstrated that anemia, which develops during the procedure, is largely responsible for the higher mortality rate in women undergoing coronary artery bypass grafting. They suggested that maintaining intraoperative hematocrit above a critical level could improve the situation.
