Similar Mortality Rates Seen in Men and Women with NSTE ACS
The gender gap appears to be closing for patients presenting with non-ST-segment elevation acute coronary syndromes (NSTE ACS) undergoing percutaneous coronary intervention (PCI), according to new evidence from a single-center registry that shows no overall difference in in-hospital or long-term mortality between men and women. However, the study, published online January 16, 2012, ahead of print in the American Journal of Cardiology, also found that women under age 60 who were biomarker-negative were more than twice as likely to die as their biomarker-negative male counterparts.
For the study, Venu Menon, MD, of the Cleveland Clinic (Cleveland, Ohio), and colleagues assessed data from 1,874 consecutive patients with NSTE ACS undergoing PCI at their institution from 2003 through 2007. Troponin status was assessed for all patients.
Early, Long-term Mortality Rates Similar
Overall, in-hospital mortality was 1.5%, with men and women showing similar rates. At a median follow up of 2.1 years, there was still no mortality difference between men and women (table 1).
Table 1. Early and Late Outcomes
All-Cause Mortality (2-yr. Follow-up)
In-hospital mortality was significantly higher among troponin-positive patients compared with troponin-negative patients (2.6% vs. 0.7%; P = 0.0006). In addition, there was a statistically significant interaction between gender and age (P = 0.012 with age as continuous variable) and between gender and troponin status (P = 0.0073). In the stratified analysis, younger women (< 60 years old) who were troponin negative had more than a twofold increase in long-term mortality compared with men (15.0% vs. 7.4%; P = 0.003).
Dr. Menon and colleagues say possible reasons for the overall improvements in mortality among women in recent years may include:
- Pervasive use of stents (used in 100% of the study population)
- Smaller sheaths and catheters
- Modern pharmacologic agents such as dual antiplatelet therapy, glycoprotein IIb/IIIa inhibitors, and bivalirudin
- Widespread statin use
Positive Message but Questions Remain
“The takeaway message is that this is adding to the body of evidence that the outcomes of PCI among patients presenting with acute coronary syndromes are similar between men and women,” said Alexandra J. Lansky, MD, of Yale University School of Medicine (New Haven, CT), in a telephone interview with TCTMD. “We’ve come a long way in improving results and outcomes, specifically mortality, in female patients.”
Dr. Lansky added that the findings regarding the biomarker-negative women confirm previous evidence that there is a subgroup of younger women that requires further study to understand why their outcomes are so much worse than those of men.
“These studies are important because they are uncovering an area that is less well understood,” she said. “While this paper does not address the ‘why,’ it does add to our knowledge.”
In a telephone interview with TCTMD, Sunil V. Rao, MD, of the Duke Clinical Research Institute (Durham, NC), added that despite the limitations of the single-center study, it raises important questions about what is happening with younger women, who would be expected to have better outcomes.
Dr. Rao offered one possible answer. “It’s pretty clear from the literature that female sex is a risk factor for both bleeding and vascular complications after PCI, and we know that both of those factors are associated with worse outcomes, so I wonder if some of the bad outcomes in the lower-risk women were related to bleeding.”
Furthermore, he added, if bleeding and vascular complications are to blame, it puts more of a priority on the safety of PCI in women. Dr. Rao’s group is currently conducting a large study of radial vs. femoral PCI to see if the radial approach results in fewer bleeding issues.
“You also wonder when you see data like these if there isn’t some underlying pathophysiology that we’re just not smart enough to figure out yet that is leading to these bad outcomes in women,” Dr. Rao added. “Then you have to consider whether there are things that weren’t measured in this study, such as adherence to evidence-based therapies.”
Societal Roles, Social Media Bear Exploring
Another relevant issue that needs further investigation, he continued, involves sociologic factors specific to women after PCI. “When they get home, is there a lack of recognition of problems because of their role as caregivers that makes them so busy they tend to forego their own health care to make sure their families are doing well?” Dr. Rao asked. “I think there is a social aspect to this that we really are not able to pin down because we haven’t asked those types of questions. Those are the kinds of things that are going to become increasingly important to study.”
New methods of improving education about cardiovascular risk factors for women also need to be examined, Dr. Rao suggested.
“Cardiology has not really been involved in social media to this point but I think there is a lot of potential there that we need to start exploring, especially when we’re talking about educating younger women,” he concluded.
At baseline, women were as likely as men to be positive for troponin (42% vs. 44%; P = 0.32). But they were more likely to be older and to have more co-morbid conditions (diabetes, COPD, obesity, and anemia).
Aspirin (325 mg) was administered before angiography and daily during the index hospitalization. Clopidogrel was given at a dose of 300-600 mg no more than 2 hours before PCI.
Kumbhani DJ, Shishehbor MH, Willis JM, et al. Influence of gender on long-term mortality in patients presenting with non–ST-elevation acute coronary syndromes undergoing percutaneous coronary intervention. Am J Cardiol. 2012;Epub ahead of print.
- The study contains no statement regarding conflicts of interest.
- Drs. Rao and Lansky report no relevant conflicts of interest.