LaVonne Borsheim’s family could not understand why she was suffering such intense pain.

Borsheim, 86, had long contended with rheumatoid arthritis and other health problems, including hip and knee replacements and heart failure. Her husband, Roger, cared for her in their small house in suburban Minneapolis, meticulously administering the prescribed daily OxyContin and oxycodone that allowed her to remain active, to ride a tandem bicycle with him and to stay involved with their Lutheran church.

But in 2018 Borsheim underwent ankle surgery and a subsequent operation to treat a resulting infection. Released from the hospital with regular home health visits, she began an alarming decline.

Her daughter Kari Shaw recalled one of their daily calls: “Dad said, ‘I think we’re losing Mom. She’s really diminishing.’” Somnolent much of the day, Borsheim was walking into walls and slumping over at the dinner table. At other times her pain grew so intense that “she was begging God to take her,” Shaw said.

Nobody suspected any wrongdoing by their apparently devoted new home health nurse, who picked up Borsheim’s prescriptions at the pharmacy and filled her pill pack. But when Borsheim took his wife to a pain clinic, blood and urine tests revealed no opioids in her system.

The family called the police.

How often do older Americans fall victim to drug diversion, in which someone steals or tampers with prescription medications, particularly opioids, for personal use or for sale? Researchers and advocates trying to protect seniors from abuse and exploitation wish they knew. The data is sparse and scattered but hints at a significant problem.

During the nation’s ongoing opioid crisis, which saw 500,000 overdose deaths over two decades, manufacturers and too many willing doctors flooded parts of the country with prescription drugs, particularly oxycodone.

“There was a rise in older-adult use that mirrored the rise in younger people,” said Dr. Michael Steinman, a geriatrician at the University of California, San Francisco, and co-director of the U.S. Deprescribing Research Network.

Researchers at the University of Mississippi, analyzing annual data from millions of Medicare beneficiaries, have reported that the proportion who received at least one new opioid prescription rose from almost 7% in 2013 to more than 10% in 2015, before subsiding to about 8% in 2016.

That year about one-third of Medicare Part D beneficiaries had at least one opioid prescription, according to the inspector general for the federal Department of Health and Human Services.

Opioids can endanger older users, increasing risks such as falls and cognitive problems and interacting harmfully with other medications. But their increasing use also makes seniors vulnerable to exploitation and abuse.

“If you need drugs, open up your grandma’s medicine cabinet,” said Pamela Teaster, a gerontologist at Virginia Tech who, with Karen Roberto, also a gerontologist there, undertook early research on drug diversion.

In some cases the theft occurs in nursing homes and assisted- living complexes. In 2019, when the National Consumer Voice surveyed 137 state and local ombudsmen who fielded complaints about long-term care facilities, more than half reported complaints about drug diversion, drug theft or financial exploitation arising from opioid addiction.

Minnesota tracks drug diversion in long-term care and found that from 2016 to 2018, documented incidents in nursing homes jumped to 116 from nine. They climbed similarly in assisted-living facilities in the state, from nine cases in 2016 to 69 two years later, then to 55 in 2019. Cases in both kinds of facilities fell back to single digits last year, possibly reflecting COVID-19-related shutdowns and restrictions.

The perpetrators, nearly always employees, developed remarkable ingenuity. An analysis of Minnesota data by Eilon Caspi, a gerontologist and researcher at the University of Connecticut, found that the thieves forged signatures, altered documents and diluted medications in syringes. Some slit open the foil backing on pill cards, substituted over-the-counter tablets and reglued the foil.

Employees walked out of facilities with pills hidden in their handbags, waistbands, bras and socks, while their patients suffered the painful consequences. Prosecutors and news organizations have reported employee arrests around the country, including in Iowa, Rhode Island, Georgia and Florida.

Often, however, victims of drug diversion live in their own homes, where the people stealing their medications are likely their own family members.

Roberto and Teaster first looked into the problem in 2017 by conducting focus groups with professionals in law enforcement, substance abuse and adult protective services in Ohio, Kentucky, Virginia and West Virginia, states with rampant opioid misuse.

“They told story after story of older adults not having access to the pain medications they needed” after relatives took them, said Roberto.

Opioid use by older adults may have plateaued, Steinman said, as federal guidelines and state drug monitoring programs have made these drugs harder to acquire and misuse. But opioids remain a vexing problem for older people, because alternative pain treatments may also be risky or ineffective.

La Vang, the registered nurse supposedly caring for Borsheim, was arrested in August 2018 and found to be substituting over-the-counter pain relievers and allergy pills for Borsheim’s medications. County prosecutors planned to offer a plea deal without jail time, since Vang had no criminal record.

“A slap on the hand,” Shaw said. Incensed, she called the federal Drug Enforcement Administration office in Minneapolis, leading to a federal indictment. Investigators discovered that Vang, 29, had been fired by two previous home health agencies for stealing patients’ drugs.

He acknowledged being addicted to opioids and entered treatment; in May 2019 he pleaded guilty in federal court to fraudulently obtaining a controlled substance.

The judge imposed an 18-month sentence in federal prison — “above the normal sentencing guidelines,” said Joel Smith, Borsheim’s attorney. A civil suit against Vang and Lifespark Home Health, his employer, was resolved this summer before trial. Vang lost his nursing license.

But for the family, the repercussions continue. Roger Borsheim died suddenly, at 87, in May 2020. “My personal opinion is that the stress of all this killed my father,” Shaw said.

LaVonne Borsheim has since moved to an assisted-living facility, where one of her three daughters visits almost daily. She feels better but remains frightened.

“Someone was coming to care for you, gained all that trust and almost killed you,” Shaw said. “Now she has such fear of being without one of us.”

“It’s heartbreaking,” she said. “How many other people did he do this to? And how many more La Vangs are there?”

© 2021 The New York Times Company