Women who undergo lung transplants are more likely than men to experience a certain type of injury afterwards, says a new study from the University of Pennsylvania.1 The research was unveiled at a conference of the American Thoracic Society in San Diego late this month.
"There are a number of possible reasons why women are at increased risk," said senior researcher Catherine Kuntz, MD, a Pulmonary Fellow at the Hospital of the University of Pennsylvania. "It may involve women's hormones or differences in their immune systems."
Last year, there were some 1,100 lung transplant procedures performed in the United States. Meanwhile, there are more than 3,600 lung transplant candidates currently on the waiting list.2 Diseases like cystic fibrosis, chronic obstructive pulmonary disease (COPD), primary pulmonary hypertension, and pulmonary fibrosis are among the reasons lung transplants are performed. It is usually considered as a last-resort option, when patients are in the advanced stages of these diseases.3
Identifying Risk Factors
Kuntz and her fellow researchers pulled records on nearly 7,500 adult lung transplant procedures performed in the United States between 1994 and 2002. Overall, they found that 10 percent of the transplant recipients experienced a type of injury known as primary graft dysfunction. The condition is described as an acute severe lung injury that takes place within 72 hours after surgery. The risk of death for these patients is also very high, contributing to an estimated half of all cases.4
Of those patients, women who received a lung from either a male or female donor were nearly 60% more likely to experience primary graft dysfunction compared to male transplant recipients.
The research team took other potential factors into account that might increase the risk of this condition, such as the donor's age, race and cause of death, as well as the recipient's age, race and reason for lung transplant. Size-matching between donor and recipient was also taken into consideration. But they still found that the sex of the recipient played more of a role in the risk than these other factors.
Injury is Apparent After Transplant
Primary graft dysfunction is primarily evident between the time that the lungs are removed from the donor and when they are transplanted to the recipient, the researchers stated. Once the lungs are removed, they are placed on ice. During this time, no blood flows through the organ. After transplantation into the recipient, blood vessels are reattached, and injury may then become apparent. Primary graft dysfunction is associated with not only a high death rate, but a prolonged hospital stay and other serious complications.
Now that Kuntz and her team discovered the risk factors associated with this condition, the next step is finding out why it happens. "We need further investigation into what it is about women that increases the risk," she said. "We need to look at factors such as whether the women have gone through menopause, and how many children they've had."
1. ATS 2005. International Conference of the American Thoracic Society. 2005 May 20-25. San Diego, CA.
2. United Network for Organ Sharing. The Organ Procurement and Transplantation Network.
3. Mayo Foundation for Medical Education and Research. Lung Transplantation: A Treatment for Life-Threatening Lung Disease. Available at: http://www.mayoclinic.com/invoke.cfm?id=HB00046.
Accessed May 26, 2005.
4. Christie JD, Kotloff RM, Ahya VN et al. The effect of primary graft dysfunction on survival after lung transplantation. Am J Respir Crit Care Med 2005 Jun 1;171(11):1312-16. Epub 2005 Mar 11.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include overseeing health news coverage for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.
