Volume: 12 (31/08/2005)
Women are twice as likely to die from complications after by-pass surgery, as compared to men, a recent study shows. Researchers think that body size is greatly responsible for this gender-related difference.
The study, led by Dr. Ron Blankenstein, cardiology fellow at the University of Chicago Hospitals, reviewed records of 15,440 patients who had undergone coronary artery bypass grafting (CABG) at 31 hospitals in the Midwestern U.S. between 1999-2000.
CABG involves taking blood vessels from elsewhere in the body and using them to reroute blood around a blockage in the arteries supplying the heart.
Researchers found that 4.24% of women died during or after surgery, as compared to 2.23% of the men in the study group. The high rate of traditional risk factors accounted for most of the difference, as the women in under study were older and more likely to have problems such as diabetes or heart failure. Another very important factor was body size, and in general, women have smaller bodies than men. Dr. Blankenstein explained the contribution of this factor by the fact that smaller bodies have smaller coronary arteries, which makes the surgery technically more complicated and survival rates poorer.
Overall, women had a 90% greater risk of death during or after surgery than men, but after considering the standard risk factors (age, co-existing diseases, body size), the gender gap narrowed to 22%. Researchers find it important to discover why this discrepancy exists, even after accounting for all these factors.
Some unanswered questions include whether body fat and hormonal differences between men and women play a role. In spite of the worrisome findings, Dr. Blankenstein is in favour of the idea that women should not be discouraged from having this type of surgery when needed. "For a lot of women, bypass still represents the best option for their disease," he says.