A new study finds that French transplant centers would have transplanted about 17,500 kidneys from nearly 28,000 deceased-donor kidneys discarded in the United States between 2004 and 2014.

If American standards are simply too high, and not instead that French patients have higher future risk, then many of the 90,000 Americans awaiting a kidney transplant could reap major benefits from the more lax standard in Europe.

This is epidemiology, the scholars do not know what happened to patients in France, they looked at data on the acceptance and use of deceased-donor kidneys in France (national CRISTAL registry) and the United States (Organ Procurement and Transplantation Network) between 2004 and 2014. During that timeframe, centers in the United States discarded about 18 percent of the 156,089 deceased-donor kidneys recovered - around two times as high as the discard rate from 29,984 deceased donor kidneys in France. 

Transplant centers in France addressed their increased need for organs by using lower-quality kidneys, the authors note. For example, the average age of a kidney donor in France was 56 years old, 17 years older than the average age of a donor in the United States. 

But how bad is good enough? Donor age is a big risk factor for organ failure, but kidneys from donors in their 50s or 60s will extend life for transplant candidates and if they are older recipients there is less concern about future problems. People over age 65 are probably better off accepting kidneys from an "extended criteria" donor - those older than 60, or older than 50 with comorbidities, such as high blood pressure - than waiting for the perfect donation to come along.

More than 35,000 people older than 60 in the United States remain on the waitlist for a kidney. "Policies designed to enhance the acceptance of donated kidneys in the United States could drive meaningful increases in the number of kidney transplants and bring the benefits of transplantation to thousands of wait-listed patients," the authors conclude.