Women who received percutaneous coronary intervention (PCI) in the U.S. from 2004 through 2014 were 20 percent more likely to die in the hospital and 81 percent more likely to experience major bleeding compared to men, according to an analysis published this month in PLOS One.
The study included more than 6.6 million procedures pulled from the National Inpatient Sample—“the largest contemporary work in this area,” noted senior author Mamas Mamas, BMBCh, DPhil, and colleagues.
About two-thirds of the procedures were conducted in men. Women were, on average, five years older, more likely to be admitted with non-ST elevation myocardial infarction (MI) and had a higher comorbidity burden.
Unadjusted rates of in-hospital mortality (2 percent versus 1.4 percent) and any in-hospital complication (11.1 percent versus 7 percent) were higher in women than in men. Even after adjusting for multiple variables, the risk of mortality was 20 percent higher in women than men, while the risk of vascular complications was 53 percent higher and the risk of bleeding complications was 81 percent higher.
“These differences in clinical outcomes persist even after adjustment for potential confounders and show that women are more likely to die in-hospital or suffer a complication than men,” wrote Mamas, with Keele University and Royal Stoke Hospital in the United Kingdom, and coauthors. “This difference is seen across all of the decade studied, and across both elective and (acute coronary syndrome) indications for PCI.”
The authors suggested the older age of women participants could be due to either delayed onset of symptoms or delays in the diagnosis of coronary artery disease and referrals for treatment.
“A differing likelihood of correct diagnosis and appropriate referral for PCI between sexes has been mentioned, and is likely to be particularly important in acute presentations such as MI, with time-sensitive outcomes from evidence-based treatments,” they wrote. “Secondly, a greater risk for bleeding appears, to some extent, inherent in female patients, as reflected in its use on bleeding risk scores.”
Also, radial access for PCI has been demonstrated to reduce bleeding risk for both sexes, but previous studies have showed higher levels of cross-over to a femoral approach in women compared to men.
Both sexes experienced an increase in procedural mortality over the duration of the study. About 10 men died per 1,000 procedures in 2004, compared to almost 24 deaths per 1,000 cases in 2014. Over that same timeframe for women, procedural fatalities jumped from just over 15 per 1,000 cases to more than 30 per 1,000 cases.
Mamas and colleagues said the trends across both sexes are likely due to the increasing age and comorbidity burden of the PCI population in the U.S., along with the increasing proportion of PCIs for acute MI versus for stable ischemic heart disease.
“It is striking that, whilst there has been a steady increase over time of in-hospital mortality after PCI, the risk ratio for women compared to men has remained fairly stable,” the researchers noted. “This probably reflects the persistence of adverse factors noted above, which disadvantage female patients in the setting of PCI, superimposed upon the profile of steadily increasing age and comorbidity that is affecting both sexes. As such, this pattern underscores the urgent need for more focused efforts to address these residual sex-specific issues, which maintain sex disparities distinct from the changing background of overall outcomes.”
The authors pointed out their study analyzed only in-hospital events, acknowledging a longer follow-up would provide “a more complete picture” of treatment outcomes.
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.