PCI Outcomes in Women vs Men
Abstract & Commentary
By Andrew J. Boyle, MBBS, PhD, Assistant Professor of Medicine, Interventional Cardiology, University of California, San Francisco. Dr. Boyle reports no financial relationships relevant to this field of study.
Source: Anderson ML, et al. Short- and long-term outcomes of coronary stenting in women versus men: Results from the national cardiovascular data registry Centers for Medicare & Medicaid services cohort. Circulation 2012;126:2190-2199.
Percutaneous coronary intervention (PCI) is performed in more than 600,000 patients annually in the United States, and women make up approximately one-third of this population. There are conflicting data on the outcomes of PCI in women vs men, and there are few gender-specific data in the contemporary PCI era.
Anderson and colleagues linked the National Cardiovascular Data Registry (NCDR) with Medicare’s database and studied 426,996 patients ≥ 65 years of age undergoing PCI between 2004 and 2008, including 180,752 women. Median follow-up was 20 months. There were significant baseline differences between the women and men, as expected. Women were older (75.8 vs 74.1 years) and were more likely to have diabetes, congestive heart failure, and hypertension. Men were more likely to have dyslipidemia, prior myocardial infarction (MI), and prior coronary artery bypass grafting. Women were more likely to have acute coronary syndromes (65.1% vs 61.5%) and less likely to have stable angina (14.9% vs 16.5%) as the indication for PCI.
Procedural success rates were similar between genders (96.3% vs 96.2%); however, women experienced more in-hospital complications than men: mortality 2.2% vs 1.6%, peri-procedural MI 1.3% vs 1.2%, bleeding 4.4% vs 2.3%, and vascular complications 1.3% vs 0.7%. Women had higher rates of in-hospital stroke (odds ratio [OR] 1.50), renal failure (OR 1.25), cardiogenic shock (OR 1.59), and incident heart failure (OR 1.59).
Long-term outcomes were statistically adjusted for > 50 variables. Although women had higher unadjusted long-term mortality, after adjustment women had a lower hazard ratio [HR] for death (0.92, 95% confidence interval [CI], 0.9-0.94). There were no differences between men and women in the rates of MI (HR 0.99; 95% CI, 0.95-1.03), bleeding (HR 0.99; 95% CI, 0.98-1.09), or repeat revascularization (HR 0.99; 95% CI, 0.97-1.02). The authors also compared outcomes based on whether bare-metal stents (BMS) or drug-eluting stents (DES) were used. After multivariable adjustment, the risk of death was lower with DES use than with BMS use in both women and men (women: HR 0.78; 95% CI, 0.76-0.81; men: HR 0.77; 95% CI, 0.74-0.79), as were the risks of MI and repeat revascularization (women: HR 0.93; 95% CI, 0.90-0.97; men: HR 0.91; 95% CI, 0.88-0.94). The authors conclude that in contemporary coronary stenting, women have a slightly higher procedural risk than men but have better long-term survival. In both sexes, use of a DES is associated with lower long-term likelihood for death, MI, and revascularization.
Commentary
This is very helpful in clinical practice and is important for several reasons. First, women historically made up a small proportion of the pivotal randomized, controlled trials that led to approval of stents. This is a very large study with a high proportion of women. Second, this study reflects the use of contemporary PCI techniques, including a large number of patients receiving DES (albeit likely first-generation DES in most). Third, the statistical techniques were robust. These factors lend weight to the conclusions drawn from these data. However, several important limiting factors should be acknowledged in interpreting this dataset. First, it is an observational study, not a prospective randomized study, and there were baseline differences between groups. Although the authors tried to address this by adjusting for more than 50 covariates, there may still be unmeasured confounders that could influence the data. Second, the authors were only able to link the NCDR and Medicare databases in 68% of cases, which may also bias the results. Third, the authors were not able to ascertain provider-specific outcomes or procedural volumes, which may affect outcomes, but the effects of such individual statistics are likely to be diluted over the more than 900 institutions reporting to the databases.
The reasons for the paradoxical early worse outcomes but better long-term outcomes in women remain unknown. The authors suggest there may be differences in pre-procedural care, such as delayed diagnosis due to atypical symptoms, that may influence early outcomes. This would be consistent with prior observational studies, but cannot be ascertained from the current dataset. Most prior studies have shown higher peri-procedural bleeding outcomes in women, which can certainly influence outcomes. This study confirmed a higher in-hospital bleeding rate in women, even after multivariable adjustment. In addition, there was a higher vascular complication rate, driven by a higher rate of pseudoaneurysms in women. The rate of radial vs femoral access, and the use of vascular closure devices are not mentioned, and these may influence the rate of pseudoaneurysm formation. Why do women fare better in the long-term? The authors suggest that perhaps after the initial diagnosis of coronary artery disease, women may receive more aggressive secondary prevention measures and more rapid attention to recurrent symptoms. Whether other factors are at play as well remains to be tested. The results of this study set the scene for further mechanistic studies into the relative benefits of medical therapy and PCI based on gender.
Percutaneous coronary intervention (PCI) is performed in more than 600,000 patients annually in the United States, and women make up approximately one-third of this population.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content