Study Identifies Gender Bias in Kidney Transplants

Because of a shortage in donor organs, many Americans with chronic kidney disease wait years for a transplant, and some die before ever making it to the first stage of the process. To add insult to injury, a recent study found strong evidence that women over 45 have a significantly less chance of being placed on a kidney transplant list than their male counterparts, even though women who receive a transplant have an equal or slightly better chance of survival. “This is different from most factors that create access to transplant disparities, such as obesity and race,” said lead researcher Dr. Dorry Segev. “Those disparities continue even once you’ve been listed—for example, blacks are less likely to get listed and, once they’re listed, are also less likely to receive a transplant.”

In order to determine access to transplantation (ATT), either through deceased donor or live-donor transplant, and survival benefits from transplantation, researchers at Johns Hopkins Medical Institutions in Baltimore examined data from the United States Renal Data System on 563,197 patients who developed end-stage kidney disease from 2000 to 2005. They found that women 45 and younger were as likely as men the same age to be placed on a transplant waiting list, but by the time women were 46 to 55, they were 3 percent less likely to be listed. The disparity grew even greater with each decade. At ages 56 to 65, women were 15 percent less likely to be placed on the list; 29 percent less likely at 66 to 75; and 59 percent less likely by the time they were 75 or older. The chance of a woman getting listed was even worse if she had additional diseases such as diabetes or heart disease. “This study suggests that there is no disparity in ATT for women in general but rather a marked disparity in ATT for older women and women with co-morbidities,” the authors concluded.

Dr. Segev said he believes the gender gap is because older women are perceived to be frailer than they really are, which subconsciously factors into the listing process. Two main steps determine who is placed on the United Network for Organ Sharing kidney transplant list: referral by a nephrologist and how the patient decides to act on that referral. “It appears as though either the nephrologist believes women have a worse chance of survival or some women don’t think they will have a good outcome,” Segev said. “Once they are listed, however, women and men have an equal chance of getting a kidney, regardless of age.”

Dr. Segev contends that this “perceived frailty” has no basis in fact, since for every age group analyzed in the study, the survival outcome for women after transplantation was equal to or slightly higher than men. “Knowing that the gender disparity is limited to older women indicates that efforts should be made to identify specific differences between older men and older women rather than general differences between all men and women in an effort to minimize the gender disparity in access to transplantation,” Dr. Segev said in a news release.

For those with advanced and permanent kidney failure, kidney transplantation may be the treatment option that allows them to live much as they did before their kidneys failed. Since the first kidney transplants were performed in the 1950s, much has been learned about how to prevent rejection and minimize the side effects of medicine. As of December 21, 2007, there were 74,182 Americans awaiting transplants.

The study was published online ahead of print in The Journal of the American Society of Nephrology.