American scientists conducted a retrospective cohort study and found that, although the frequency of serious complications in heart and vascular surgeries is comparable in men and women, the lives of the latter are less likely to be saved. A report on the work was published in the journal JAMA Surgery.
Statistics show that women have higher mortality rates than men in high-risk surgeries. This is generally attributed to the fact that women have higher perioperative risks, as they are more likely to be admitted to such surgeries at an older age and with more comorbid conditions. However, the question of whether this is due to a higher incidence of complications or to the fact that the volume of care provided for them is less remains open.
To figure this out, 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 mean age at surgery was slightly higher in women than in men (74.8 vs. 73.4 years), as was the mean number of comorbid conditions (Elixhauser index ≥ 2 in 86.4 vs. 83.2 percent). Women were more likely to have 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.
They included myocardial infarction, pulmonary embolism, pneumonia, postoperative bleeding, and infection of the operated area. Statistical data processing was performed using logistic regression models with adjustments for gender, age, 27 comorbid conditions, year of surgery, indications (emergency or planned), and type of intervention.
After introducing all the adjustments, it turned out that the frequency of serious complications was comparable in women and men — 14.98 versus 14.37 percent. At the same time, the level of failures to save lives in women was significantly higher: 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). At the same time, repeated surgeries were performed more often in men. Similar patterns were observed in the analysis for individual types of interventions. Thus, despite a similar frequency of serious complications, the probability of death after high-risk surgeries is higher in women, which may indicate that clinicians are not making enough efforts to save them. Improving modern recognition and adequate treatment of complications in women can reduce this difference between patients of different sexes, the authors of the study conclude. Previously, American, Austrian and Swedish researchers showed that the higher mortality rate of women during coronary artery bypass surgery is largely due to anemia developing during the procedure. In their opinion, maintaining intraoperative hematocrit above the critical level can correct the situation.