According to the Centers for Disease Control and Prevention, the US “is in the midst of a prescription painkiller overdose epidemic,” and opioids are a key culprit, responsible for 44 deaths each day. But according to a new study, a patient’s risk of death from an opioid overdose may be influenced by the dosage they are prescribed.
First author Amy Bohnert, PhD, of the Department of Psychiatry at the University of Michigan in Ann Arbor, and colleagues recently published their findings in the journal Medical Care.
Opioids are a class of drugs used to treat chronic pain. They work by lowering the intensity of pain signals that are sent to the brain. Some common forms of opioids include codeine, hydrocodone, oxycodone and methadone.
Overprescription of opioids has been cited as a major factor for opioid abuse and death in the US; while there has been no overall change in rates of chronic pain in the US in recent years, the amount of prescription painkillers prescribed and sold in the country almost quadrupled between 1999-2013.
But what about the strength of opioids that are prescribed to patients? Current prescription guidelines recommend that doctors should not prescribe opioids at a daily dose above 100 morphine-equivalent mg (MEM).
However, the new study from Bohnert and colleagues suggests these guidelines may need to be reviewed, after finding that opioids prescribed at less than half the dose of current maximum daily recommendations may still lead to accidental overdose death for some patients.
To reach their findings, the team analyzed the medical records of 221 veterans who died of accidental opioid overdose, alongside the medical records of 221 veterans who were prescribed opioids for chronic pain but who did not overdose on the drugs.
The researchers found that the average daily prescribed dose of opioids for the overdose group was more than double that of those who did not overdose; veterans in the overdose group were prescribed an average of 98 MEM daily, compared with an average of 48 MEM daily in the non-overdose group.
Even after excluding patients who were prescribed super-high-dose opioids of 300 MEM daily, the difference between the two groups remained, according to the authors.
The researchers say they were unable to identify an exact dosage that increased patients’ risk of opioid overdose, noting that some individuals in the overdose group were prescribed doses at less than 50 MEM daily.
However, after developing a model of all opioid doses that both groups of veterans received, the team concludes that lowering maximum prescription strengths to below 100 MEM daily could reduce the likelihood of overdose for those most at risk, while affecting few low-risk patients.
Commenting on the findings, Bohnert says:
“As the United States grapples with the rising toll of accidental overdoses due to opioids, our findings suggest that changing clinical practices to avoid escalating doses for patients with chronic pain could make a major difference in the number of patients who die.”
Additionally, she says that avoiding the prescription of large opioid doses that go into patients’ homes lowers the chance of the drugs being taken by family and friends – particularly children and adolescents; according to the Centers for Disease Control and Prevention (CDC), around 26% of individuals who use opioids get them free from friends and relatives.
“This is important because an opioid that is a larger dose per pill, compared to a smaller one, is going to be deadly to a child or adult who hasn’t been taking the medication regularly,” adds Bohnert.
In December 2015, Medical News Today reported on a study that found 90% of patients with chronic pain who overdose on opioids continue to be prescribed the drugs.