A study from Columbia University Medical Center discovered that being diagnosed with a chronic pain condition is the biggest risk of dying from an opioid overdose. The study, which reviewed more than 13,000 overdose deaths, found that more than 60 percent of those who died from an opioid overdose had been diagnosed with a condition that caused chronic pain, and many had been diagnosed with a psychiatric disorder.

The researchers analyzed clinical diagnoses and prescriptions for adults in the Medicaid program who died of an opioid overdose. During the last year of life, more than half of these individuals had been diagnosed with chronic pain. Many had also been diagnosed with depression and anxiety.

"The frequent occurrence of treated chronic pain and mental health conditions among overdose decedents underscores the importance of offering substance use treatment services in clinics that treat patients with chronic pain and mental health problems," said lead author Mark Olfson, M.D.

"Such a strategy might increase early clinical intervention in patients who are at high risk for fatal opioid overdose," he continued.

Approximately one-third of those who died had been diagnosed with a drug use disorder in the prior year. However, fewer than one in twenty had been diagnosed with opioid use disorder in the last month.

"Because clinical diagnoses generally indicate treatment, this service pattern suggests that dropout from drug treatment is common before fatal opioid overdose," said Olfson. "Improving treatment retention with contingency management or other effective behavioral interventions might help lower the risk of fatal overdose in these patients."

In the year before death, more than half had filled prescriptions for opioids or benzodiazepines, and many had filled prescriptions for both types of medications. Benzodiazepines are used to treat anxiety and insomnia and include Xanax, Librium, and Valium.

"This medication combination is known to increase the risk of respiratory depression, which is the unusually slow and shallow breathing that is the primary cause of death in most fatal opioid overdoses," said Dr. Olfson.

The study was published online in the American Journal of Psychiatry.

Opioid abuse and overdose has become a national public health crisis. The National Institute on Drug Abuse estimates that approximately 2.1 million are addicted to prescription opioid pain relievers.

Opioids are also implicated in fatal car crashes. A study by Columbia University's Mailman School of Public Health found that the percentage of fatally injured drivers who tested positive for prescription drug opioids rose from 1 to 7 percent from 1999 to 2015.