Women Versus Men Regarding Outcome of CABG or PTCA
To the Editor:
It is very gratifying to read from the report from the Bypass Angioplasty Revascularization Investigation (BARI)1 that women who undergo coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA) fare as well as men. However, this conclusion seems to be at odds with another report2 published at about the same time and based on a much larger number of patients (344 913 compared with 1829 in BARI). The registry from the Society of Thoracic Surgeons2 reported that women clearly have a higher mortality rate within 30 days of a procedure (4.52% in women versus 2.61% in men; P<0.001). The report, after adjusting the data for more than 50 potential risk factors, still found a statistically significant higher death rate for women.3
Conventional wisdom tells us that women are at higher risk than men for CABG and PTCA because women have smaller, more technically challenging coronary arteries; there is less frequent use of internal mammary artery grafting in women; women develop symptoms from coronary artery disease at an older age than men owing to protection from estrogen; and women are more likely as a result to have such comorbid conditions as diabetes mellitus and renal disease that increase the operative risks.
The issue of whether men do better than women or women do equally well as men in outcomes with CABG and PTCA remains debatable. But the most important message from BARI1 is that it is reassuring that women do not seem to do worse and therefore gender of the patient should not influence a physician’s decision to recommend medical versus surgical treatment of coronary artery disease.
- Copyright © 1999 by American Heart Association
Jacobs AK, Kelsey SF, Brooks MM, Faxon DP, Chaitman BR, Bittner V, Mock MB, Weiner BH, Dean L, Winston C, Drew L, Sopko G. Better outcome for women compared with men undergoing coronary revascularization: a report from the Bypass Angioplasty Revascularization Investigation (BARI). Circulation. 1998;98:1279–1285.
Winslow R. Gender effect in heart surgery is disputed. Wall Street Journal. September 29, 1998:B12.
We appreciate the comments of Dr Cheng, who notes that the finding of a similar outcome in women and men undergoing CABG within the Bypass Angioplasty Revascularization Investigation (BARI)R1 is not corroborated in a large registry of patients in the Society of Thoracic Surgeons National Cardiac Surgery Database.R2
As stated in the Discussion, interpretation of our results in BARI should take into account that the data are from a randomized clinical trial with specific inclusion and exclusion criteria, and hence, the BARI population is not representative of all patients undergoing coronary revascularization. However, when we examined BARI screening data, we found that women were not disproportionately excluded from the trial population. In addition, data from an ancillary BARI study that conducted a survey of all hospitals in the United States performing CABG and coronary angioplasty during the same time period indicated that the proportion of women undergoing revascularization procedures at BARI sites was similar to the proportion of women undergoing revascularization at a random sample of hospitals around the country (between 26% and 27% of patients and similar to the 26.7% of women in the trial).R3 Thus, there does not appear to be a sex bias for selection into BARI. Similar to other observational studies, women in BARI were older and had a higher risk profile and more comorbid disease than men. However, the detailed inclusion criteria, most notably that the coronary anatomy had to be amenable to both CABG and coronary angioplasty, suggest that the BARI population represents a subset of all patients treated with CABG.
We agree with Dr Cheng that it is unclear whether women do as well as men when undergoing CABG and coronary angioplasty. However, what is important is that the outcome of women undergoing coronary revascularization appears to be improving, as suggested in 2 recent preliminary reports that noted a similar adjusted mortality in women and men undergoing percutaneous coronary intervention within the NHLBI Dynamic RegistryR4 and the Northern New England Cardiovascular Disease Study Group registry.R5 These data should be disseminated to clinicians to ensure optimal management of women in need of a coronary revascularization procedure.
Jacobs AK, Kelsey SF, Brooks MM, Faxon DP, Chaitman BR, Bittner V, Mock MB, Weiner BH, Dean L, Winston C, Drew L, Sopko G. Better outcome for women compared with men undergoing coronary revascularization: a report from the Bypass Angioplasty Revascularization Investigation (BARI). Circulation.. 1998;98:1279–1285.
Edwards FH, Carey JS, Grover FL, Bero JW, Hartz RS. Impact of gender on coronary bypass operative mortality. Ann Thorac Surg. 1998;66:125–131.
Jacobs AK, Yeh W, Kelsey SF, Williams DO, Detre KM. Gender differences in patients undergoing contemporary percutaneous coronary intervention: the 1997–98 NHLBI Dynamic Registry. Circulation. 1998;98(suppl I):I-198. Abstract.
Malenka D, O’Rourke D, Robb J, Wennberg D, McGrath P, Kellett M Jr, Ryan T Jr Watkins M, Allen F, VerLee P, Bradley W, Hettleman B, Shubrooke S. Improving outcomes for women following percutaneous coronary interventions (PCI’s) in 1994–97. Circulation. 1998;98 (suppl I):I-196. Abstract.