Coronary artery disease (CAD) has traditionally been thought of as a disease that predominantly affects men. Women, however, are more likely than men to die from a myocardial infarction (MI). Despite increased awareness of heart disease in women and improved outcomes after percutaneous coronary intervention (PCI), women with MI have more mortality and delays to treatment than men. Although all of the reasons behind these differences are not clear, women presenting with MI are a more morbid patient population than their male counterparts. Women consistently demonstrate higher baseline risk, including older age, higher rates of diabetes mellitus (DM), hypertension (HTN) and congestive heart failure (CHF) . This was initially demonstrated in trials conducted in the thrombolytic era, but has persisted in the current era of PCI .
Another source of sex disparity in ST-elevation MI (STEMI) management is delay to treatment. It is well established that the benefit of PCI over fibrinolytic therapy is lost with delay in administering treatment. A meta-regression analysis of 23 randomized controlled trials in 2003 showed that for every 10-minute delay in PCI (defined as the difference between door to balloon and door to needle), the favorable reduction in mortality is reduced by 0.94% ( P =.016). When the delay in PCI is 62 min, there is no longer a reduction in mortality with PCI over fibrinolytics . Unfortunately, studies have shown that women make up a higher percentage of patients in the more delayed door-to-balloon (DTB) time, as well as total ischemic time . The cause for this delay in STEMI treatment is unknown. Difficulties in recognizing symptoms in women on the part of the patient may be where the problem begins. Many large-scale campaigns have addressed educating the public on recognizing the symptoms of MI. Once women with suspected MI present to the health-care system, however, it is the responsibility of the health-care provider to diagnose and treat STEMI in a timely fashion. Unfortunately, delays in DTB and total ischemic time are evidence that the system is flawed from a provider’s standpoint as well.
Disparities in the management of women with CAD warrant further investigation, but whether these differences translate into disparities in outcomes between men and women remains controversial. Studies have shown that women with acute MI have higher rates of in-hospital death and complications, including major bleeding, than do men with acute MI . In some of these analyses, baseline risk at least partially accounted for the higher death rate in women . More concerning, however, is that, in many cardiac studies, female sex is an independent predictor of early death and adverse events.
In the In the Global Use of Strategies To open Occluded arteries in acute coronary syndromes (GUSTO V) study, reteplase vs. abciximab plus half dose reteplase were compared in patients with STEMI or new left-bundle branch block. Female sex was an independent predictor of 30-day mortality even after adjusting for potential confounders (OR 2.00; 95% CI 1.59–2.53) . The CADILLAC trial assessed treatment with primary PCI using PTCA vs. bare metal stenting. Women had higher rates of in-hospital complications and adverse events, as well as higher rates of major adverse events, death and bleeding at 30 days and 1 year. After adjustment for baseline characteristics, female sex remained an independent predictor of major adverse cardiac events at 1 year (HR 1.64; 95% CI 1.24–2.17, P =.0006) .
A more recent analysis of STEMI treatment with primary PCI highlights these sex disparities in the MI population. This study of the GWTG-CAD registry analyzed 78,254 patients with acute MI. At baseline, women were older and had more comorbidities than their male counterparts. After adjusting for these differences in baseline characteristics, the DTB time was longer in women (103 vs. 95 min, P <.0001), but door-to-needle time was longer as well (47 vs. 39 min, P <.0001). In the STEMI subpopulation, women had higher rates of in-hospital mortality even after adjustment for potential confounders, as female sex became an independent predictor of in-hospital death (OR 1.12; 95% CI 1.02–1.23, P =.015). Interestingly, these differences were accounted for by an excess of very early deaths (within the first 24 hours of presentation) in women . It is unclear, however, whether these early deaths could be explained by treatment differences or by women dying before the proper therapies could be administered.
A current study of the MI population at Washington Hospital Center aimed to further examine this sex disparity. A total of 825 consecutive patients diagnosed with STEMI and treated with primary PCI (273 women, 33%) were evaluated. In-hospital outcomes were compared between men and women. At baseline, women were older, more likely to be African American and have a history of diabetes. Despite the fact that men and women had similar median DTB (women 167 [range 123–250] vs. men 153 [range 117–250] min, P =.1287), women had longer hospital stays, in-hospital renal failure, more transfusions and higher rates of in-hospital death ( Table 1 ). On multivariate analysis, after adjustment for comorbidities, only cardiogenic shock (OR 27.0, 11.2–65.1, P <.001) and age (OR 1.05, range 1.02–1.08, P =.001) were independent predictors of in-hospital death ( Table 2 ). This analysis further emphasizes that women presenting with MI represent a morbid patient population with higher rates of in-hospital death after treatment with primary PCI. Although equal DTB times may represent progress in identifying signs and symptoms of MI, addressing comorbidities that plague the female population at disproportionate rates may address the disparity overall.
| Female | Male | P | |
|---|---|---|---|
| Age, mean±S.D. | 64.78±15.35 | 59.03±12.85 | <.001 |
| African American | 39.6 | 29 | .002 |
| History of myocardial infarction | 81.7 | 87.3 | .042 |
| Diabetes | 36.2 | 26.0 | .003 |
| HTN (%) | 87.9 | 83.3 | .084 |
| Chronic renal insufficiency | 11.1 | 12.3 | .617 |
| Cardiogenic shock | 25.3 | 20.2 | .096 |
| Length of stay (days), mean±S.D. | 6.38±6.23 | 5.39±5.52 | .027 |
| Intensive care unit (days), mean±S.D. | 3.20±3.62 | 2.35±2.41 | .005 |
| Post-PCI reinfarction | 49.6 | 52.5 | .446 |
| Transfusion | 21.3 | 10.9 | <.001 |
| Renal insufficiency in-hospital | 15.6 | 6.7 | <.001 |
| Death in-hospital | 9.9 | 5.3 | .014 |
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
