Researchers perform meta-analysis to determine risks to kidney donors

A study published in the Annals of Internal Medicine identified new risks to kidney donors that include concerns about escalating blood pressure and increased odds for preeclampsia.

Linda M. O’Keeffe, PhD, and researchers at the University of Cambridge and Bristol University performed a systematic review and meta-analysis of 52 published studies, representing more than 100,000 living kidney donors. Researchers also reviewed the outcomes of more than 110,000 non-donors to assess the midterm and long-term health risks associated with living kidney donation in adults.

Data showed kidney donors had higher diastolic blood pressure, poorer renal function and a greater risk of end-stage renal disease (ESRD) than non-donors. Female kidney donors had an almost two-fold greater risk than non-donors for pregnancy-related complications, such as preeclampsia.

The researchers found no evidence that living kidney donors had a greater risk for mortality, cardiovascular disease, type 2 diabetes or reduced quality of life. He suggested that the findings may be used to inform prospective donors of the risks associated with kidney donation. “Compared with non-donor populations, living kidney donors have no increased risk for several major chronic diseases, with the exception of ESRD. However, the absolute risk for this disease remains low,” they wrote.

In an accompanying editorial, Cleveland Clinic and University of Pennsylvania kidney specialists Emilio D. Poggio, MD, and Peter P. Reese, MD, MSCE, wrote that despite 6 decades of living kidney donation, large and high-quality studies of ESRD and other relevant outcomes after donation have been completed only in the past decade. However, challenges remain in these comparative studies.

“Determining the health consequences of kidney donation poses major methodological challenges, which include identifying an equally healthy group of nondonors for comparison,” they wrote. “O’Keeffe and colleagues rated the quality of these comparison groups in the studies in their analysis and found that most comparison nondonors were probably not as healthy as living kidney donors.”

While the systematic review and meta-analysis provide some important answers, the profession is still a long way from offering precise risk estimates to prospective donors, they wrote.

“[A] close look at the data reminds us that long-term outcomes are uncertain and that precision medicine has not arrived for risk prediction in kidney donors. In the meantime, we should do our best to protect potential donors with careful selection, candor about harms, open discussion about unknowns and a commitment to their lifelong health after nephrectomy. Those goals give us plenty of work to do,” Poggio and Reese wrote.

References:

O’Keeffe LM, et al. Ann Intern Med. 2018, doi:10.7326/M17-3249.

Poggio ED, et al. Ann Intern Med. 2018;doi:10.7326/M17-1235.