Women over the age of 65 who need heart bypass surgery are more likely than men to receive care at lower-quality hospitals, which leads to higher death rates, according to a major study by Michigan Medicine.
The research, published in JAMA Network Open, reviewed nearly 450,000 Medicare patients who underwent coronary artery bypass grafting (CABG) between late 2015 and early 2020.
Heart bypass surgery is a common procedure used to treat serious heart disease by rerouting blood around blocked arteries. But not all hospitals have the same track record for success. The study found that hospitals with the highest death rates within 30 days of surgery were more often where women were treated—especially women over 65.
The numbers are troubling. Women were 1.26 times more likely than men to have their surgery at these low-performing hospitals. Among patients at such hospitals, 7% of women died within 30 days after surgery, compared to nearly 5% of men.
This difference in outcomes became even more striking when comparing high-quality hospitals to low-quality ones—the gender gap in death rates more than doubled.
Lead author Dr. Catherine M. Wagner, a surgery resident at the University of Michigan, said, “Women are more likely to die after heart bypass surgery and more likely to have the surgery at low-quality hospitals. We need to improve these hospitals and ensure women are referred to better hospitals to reduce this gap.”
The study also revealed that women tend to have more existing health conditions before surgery and are more likely to be admitted to the hospital unexpectedly. Earlier research has shown that women with heart disease are often referred for surgery later than men, possibly due to biological differences or delays in recognizing symptoms.
Another key finding was that hospitals performing a higher number of heart bypass surgeries tend to have better results. This was especially true for patients considered at moderate or high risk. Better outcomes in high-volume hospitals suggest that referring women to these centers could make a significant difference.
Dr. Andrew Ibrahim, co-author of the study and a professor of surgery, explained, “The differences in outcomes we see are likely due to both patient risk and the quality of care at each hospital. Improving referrals for women to high-quality centers and increasing gender diversity in cardiothoracic surgery could help reduce this disparity.”
National data adds urgency to the issue. A 2023 report showed that death rates for women undergoing heart bypass surgery rose between 2011 and 2020, while men’s outcomes stayed more stable. This led to a call to action in JAMA Surgery, urging doctors and hospitals to improve care for women with heart disease.
In response, the White House launched its first-ever Initiative on Women’s Health in November 2023. Soon after, the Department of Health and Human Services announced a $100 million investment in women’s health research and innovation.
Despite some improvements in surgical techniques and recovery, Dr. Wagner stressed that there is still a long way to go. “Our study shows that better care at low-quality hospitals and fairer referrals of women to high-quality hospitals could help close these long-standing gaps,” she said.
“It’s an exciting time for research in women’s cardiovascular health, and I am hopeful that with this renewed focus, we will achieve better outcomes for women undergoing heart surgery and improve care for all patients.”
This research highlights the importance of not only improving the quality of care at lower-performing hospitals but also addressing long-standing gender differences in how heart disease is treated.
For those interested in heart health, new studies suggest that vitamin K may reduce heart disease risk by a third, and a year of regular exercise can even reverse early signs of heart failure. Other research has looked into supplements and foods that may increase or decrease the risk of heart disease and stroke.
The full findings of this important study are available in JAMA Network Open.
If you care about heart health, please read studies about top 10 foods for a healthy heart, and how to eat right for heart rhythm disorders.
For more health information, please see recent studies about how to eat your way to cleaner arteries, and salt and heart health: does less really mean more?
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