Diana Teller never thought she was too old for anything, not scuba diving or traveling the world or taking Italian lessons late in life, her family recalled.

So when the vivacious San Diego woman died last year at age 76 after a sudden brain hemorrhage, no one questioned whether she was too old to be an organ donor.

“I guess I never really thought of her as her age,” said daughter Lori Teller, 57. “This was something she wanted to do.”

Despite such convictions, donations from senior citizens like Teller — whose corneas, kidneys, liver and tissue were used — rarely happen. Of the 9,079 deceased organ donors in the U.S. in 2015, only 618 were aged 65 or older, according to the Organ Procurement and Transplantation Network, or OPTN.

That’s due in part to U.S. policies and practices that often impose age cut-offs and strict federal regulations that penalize centers for poor outcomes, potentially reducing the organ pool in a nation where nearly 120,000 people await transplants, experts say.

But a new study by researchers at the University of Torino in northwest Italy suggests that age alone should not exclude older organs — in this case kidneys — from consideration.

A review of nearly 650 kidneys transplanted from deceased donors aged 50 to older than 80 from 2003 through 2013 found that patient survival and organ function was high, even among the oldest donors.

“According to these findings, organs from extremely aged donors represent a resource that should be accurately evaluated,” wrote Dr. Luigi Biancone, a nephrologist and lead author of the study published Thursday in the Clinical Journal of the American Society of Nephrology.

The study echoes previous research and bolsters a growing view in the U.S. that older organs should be considered for some patients, said Dr. David Klassen, chief medical officer of the United Network for Organ Sharing, or UNOS, the nonprofit group that oversees the nation’s transplant system. He was also medical director of the kidney and pancreas transplant programs at the University of Maryland Hospital for nearly 30 years.

“The conversation in this country has been recognizing that there’s potential in transplanting organs from older donors,” he said. “The take-home message is that age by itself should not be a deal-breaker.”

In the U.S., more than 99,000 people await kidney transplants, including many in states like California, where it can take a decade to obtain an organ from a recently deceased donor. At the same time, more than 3,100 kidneys were discarded last year, often because of questionable quality, including 515 from donors older than 65, according to OPTN.

The new study found that five-year patient survival rates were high — 88 percent to 90 percent — including in 265 patients who received kidneys from donors in their 70s and 27 who got organs from donors older than 80. The five-year survival of the kidneys was robust, too, ranging from nearly 66 percent in this age group to more than 75 percent across all age groups.

The kidney discard rate, the percent rejected by surgeons, ranged from about 15 percent to 20 percent in groups of donors younger than 80, the study found. But it was markedly higher in the octogenarian group, with 48 percent of the organs turned down, mostly because of age-related problems.

Still, that means about half of those organs could be used, Biancone noted, especially if older donors were matched with older recipients.

In the U.S., donation from the oldest donors is increasing slowly. Last year, livers from two deceased donors older than 90 were transplanted, data show. Another 33 organs were recovered from 27 donors aged 80 to 89.

Many organ procurement organizations, or OPOs, actively seek elderly donors — a fact that surprises many families approached about donation, said Lisa Stocks, executive director of Lifesharing, the San Diego OPO that helped arrange Teller’s donation.

“If they’re over 65, they think if they’re retired, their organs are retired, too,” she said.

The cutoff for seeking donations is age 80, up from a cutoff age of 65 more than a decade ago, Stocks said. There’s a similar policy at LifeCenter Northwest, which oversees donations in Alaska, Montana, north Idaho and Washington state, said executive director Kevin O’Connor.

“We would not consider a patient over age 80 as an organ donor here,” he said. “We do pursue cases in their late 60s.”

Older organs can be hard to place, especially at transplant centers worried about strict federal rules linking Medicare participation to one-year graft and patient survival outcomes in those transplanted over 2 1/2 years.

“There’s been a lot of concern about the outcomes of older donors if transplant program outcomes are lower,” said Klassen, the UNOS chief medical officer. Low scores make some centers leery, he added.

A 2008 study in the journal Transplantation analyzed OPTN data from more than 600 deceased kidney donors older than 70. It found that transplants were associated with a higher risk of kidney loss and patient death.

No question, the average quality of organs typically declines with age, said Dr. Robert Steiner, co-director of transplant nephrology at UC San Diego Health and medical director of Lifesharing.

But there are many exceptions, Steiner said.

“When you measure kidney function in people in their 70s, some people have function as good as a 20-year-old,” he said. “You just have to find these people.”

A 2014 change in the way kidneys are allocated in the U.S. is one way of measuring. Each organ is now scored on a 100-point scale, the Kidney Donor Profile Index, or KDPI, that estimates how long the kidney is likely to function compared to others. A score of 85 percent, for instance, means that the kidney is likely to function longer than just 15 percent of available organs.

“As a general rule, you wouldn’t put a kidney from an 80-year-old into a 22 year-old,” Klassen said. But it can be appropriate to transplant that kidney into one of the more than 22,000 people older than 65 on the waiting list.

Biancone, the author of the latest study, acknowledges that his work is a retrospective look from a single center. Still, he said the research suggests that very elderly donors are a “valid source of organs.”

In Diana Teller’s case, her organs and tissues benefited more than 50 people, including a 65-year-old man in California who received a kidney.

He declined to be identified publicly, but Sharon Ross, a Lifesharing spokeswoman, said he is doing well.

“The timing of her gift saved him from going on dialysis,” she said.

Lori Teller hopes to meet the recipient soon to tell him about her mom, who was one of several organ donors honored on a Rose Parade Float on New Year’s Day 2016.

“The fact that she wanted this and that this was able to happen was really helpful,” Teller said. “It helped us understand that life goes on, in a way, through her.”

KHN’s coverage of end-of-life and serious illness issues is supported by The Gordon and Betty Moore Foundation.