Roughly 4 million Americans too disabled to work are prescribed heavy-duty painkillers, such as OxyContin, Vicodin, codeine and morphine, according to a new study from the Dartmouth University School of Medicine in New Hampshire.
The study also found that one in five of those prescriptions are for doses so high that they put patients at risk for serious side effects and even overdose.
Plus, it's not even clear that the drugs help.
"We don't know whether that practice is safe, and we don't know if it's effective," said Michael Von Korff, an epidemiologist with the Group Health Research Institute in Seattle, who was not involved in the work.
The Dartmouth study examined the prescription records of the 9 million Americans who receive Medicare benefits because they have become too disabled to work — largely because of muscle or joint pain.
Some of those prescriptions are certainly necessary, but other patients would likely do better with a combination of physical therapy, exercise and non-drug treatments, Von Korff said.
"Almost half — over 40% — filled a prescription for opiates in a year, and one in five was filling six or more prescriptions per year," said Ellen Meara, an economist and associate professor at Dartmouth, who helped lead the research.
Many of those people were taking extremely high doses. "The risks of dying are much higher when you start to exceed 100 mg of opioids a day," said Meara, who estimated that 220,000 Medicare recipients receive a dose that high; many of them twice as much.
Cindy Reilly, director of the prescription drug abuse project at the Philadelphia-based Pew Charitable Trusts, said she found those dose amounts "astounding" and "staggering."
"There's a significant risk for patient harm associated with that," Reilly said. The Medicare recipients could be at even higher risk than most people for issues like falls, drowsiness and mobility problems, she said, because they are already disabled.
The Dartmouth study also showed substantial differences by state, with some, such as Tennessee and Florida, showing both high rates of opioid use and high prescribed doses. State laws vary in how much they restrict opioid prescription; both Tennessee and Florida have relatively permissive laws, Meara said.
Opioid use jumped substantially in the late 1990s into the early 2000s, previous studies have shown. That increase brought with it some unintended consequences — including large increases in addiction and overdose, said Daniel Carr, who directs the Pain Research, Education and Policy Program at the Tufts University School of Medicine in Boston.
Since those consequences were recognized in around 2010, there has been a call to reduce opioid prescriptions, Carr said. The Dartmouth Medicare data showed that prescription rates leveled off around that time.
Recent research has shown that drugs like morphine, hydromorphone and fentanyl, are useful for patients suffering the pain of advanced cancer. But the benefits are less clear for conditions like headaches, muscle pain and arthritis.
"I'd say many of the leading authorities would encourage caution in using opioids for long-term management of back pain," Von Korff said. "Pretty much everyone agrees that the risk of overdose and addiction are considerable, and greater than we thought."
