A study published in the November issue of the journal Pain found an increased risk of death associated with chronic pain without opioid treatment, as well as an even higher risk among those prescribed opioids for long-term use and a somewhat lower risk associated with short-term use.
“Our study provides the first evidence that directly links legally prescribed opioids to risk of deaths related to short- and long-term opioid use in patients with chronic non-cancer pain,” said lead investigator Ola Ekholm, National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
In the United States and Denmark, about 3% to 5% of the populations are using opioids regularly for treatment of chronic pain. From 1999 to 2010, the number of US dispensed opioid prescriptions doubled (120 million to 210 million), and during the same period annual deaths related to opioid overdoses quadrupled from 4,030 to 16,651.
Using data from 2 Danish Health and Morbidity surveys from 2000 and 2005, combined with information from official Danish health-care statistics and socioeconomic registers, researchers found that the risk of all-cause mortality was 1.72 times higher among long-term opioid users and 1.39 times higher among non-opioid-using chronic pain patients than among individuals without chronic pain.
Although the study showed no statistically significant association between long-term opioid use and cardiovascular and cancer mortality, the results indicated that risk of death due to other causes was almost 2.4 times higher among long-term opioid users than among individuals without chronic pain.
The investigators also determined that long-term opioid users had 4 times higher risk of toxicity/poisoning by drugs, medications, and biological substances than individuals without chronic pain.
Non-opioid users with chronic pain also had a higher mortality risk but did not present with higher risk for poisoning by drugs, medications, and biological substances. They did, however, have a slightly higher risk for injury, poisoning, and certain other consequences of external causes when compared with individuals without chronic pain.
In an accompanying commentary, Harald Breivik, MD, and Audun Stubhaug, MD, University of Oslo, and Oslo University Hospital, Oslo, Norway, said that the most robust finding in the study is the higher mortality rate in patients with chronic pain not using opioids compared with persons without pain. They noted that opioids may aggravate this burden of disease in patients with chronic pain, but it remains to determine whether this higher mortality rate is caused by the opioid treatment or the seriousness of the pain problem.
“Safe and effective treatment of opioid-sensitive pain is possible but continues to be a double-edged sword that is difficult to handle,” they wrote. “It requires deep pharmacological knowledge, experience, resources, considerable patience, and mental energy from a group of helpers who are able to take care of the whole bio-psycho-social conundrum of the chronic pain patient.”