Online tool created at Johns Hopkins helps doctors identify best kidney donor candidates

An online tool developed at the Johns Hopkins Bloomberg School of Public Health helps forecast the long-term risk of kidney failure by weighing a variety of factors and could help identify good candidates to be living kidney donors—including older donors, who have been typically passed over. Despite excellent outcomes in those who have received kidney transplants from older donors, fewer than 3 percent of live kidney donors in the U.S. in 2014 were 65 years or older.

Researchers from the Chronic Kidney Disease Prognosis Consortium at Johns Hopkins shared their findings in today's issue of the New England Journal of Medicine.

"Use of this online tool during the evaluation process gives decision-makers the evidence to help them decide who can most safely donate a kidney for transplant," says study author Morgan Grams, a nephrologist and assistant professor of epidemiology at the Bloomberg School. "This assessment could minimize the number of living kidney donors who go on to develop kidney failure, support donation among people who were previously believed to be poor candidates, and enhance informed consent and decision-making with potential donors."

The new tool assesses 10 health and demographic factors—including age, race, smoking status, and blood pressure—to calculate the risk of kidney failure at both 15 years and over a lifetime. This provides a broader picture than the existing assessment criteria, which usually focus on just one risk factor at a time.

JHU researchers developed the tool to help evaluate, counsel, and approve living kidney donor candidates. According to the United Network for Organ Sharing, there were 122,662 people waiting for kidney transplants in the U.S. as of Oct. 31.

For the study, researchers looked at data from nearly 5 million Americans who participated in seven large studies to project the long-term incidence of kidney failure in people with two kidneys.

"Our ultimate goal is to develop a tool where we can sit down with a potential kidney donor and say: This is your risk if you don't donate, and this would be your risk if you do donate, so you can decide if you feel the risk is too high," says Dorry Segev, a Johns Hopkins transplant surgeon involved in the research.