Opioids May Not Be Solution for Chronic Non-Cancer Pain
In the late 1990s, the United States government made it easier for doctors to order opioids (narcotics) to help relieve pain not caused by cancer, called chronic non-cancer pain. As a result, the prescriptions of opioids has grown so doctors could help treat patients living with chronic pain. Some studies showed that these medications could help treat chronic pain, however some of it wasn't very strong.
Now, over 10 years later, it still isn't really known who well opioids relieve non-cancer pain. One large study, done in Denmark, was unable to find a significant difference between patients who took opioids and those who used other methods of pain relief. In addition, there are dangers associated with increased use of opioids, including overdoses and poisoning. For this reason, it's important to identify how much good these medications are doing for patients with chronic non-cancer pain.
The authors of this article undertook a study to determine the patterns of opioid prescription and morphine equivalent doses over a one-year period for patients with back injuries, the factors related to long-term opioid use, association of opioid use and pain and function, and the quality of doctor-related documentation of opioid use.
The study group consisted of 1,843 workers with back injuries. They were interviewed about 18 days after their first claim submission and again after a year. To participate in the study, workers had to be at least 18 years old, have lost four or more days from work due to the injury, and have had at least one day of pay compensation within the year. The researchers determined the injury severity by going through the workers' records and a computerized medical billing database was used to determine opioid use.
The first interview was done by phone. The workers were asked about their socioeconomic status, pain and function, healthcare, lifestyle (such as smoking), and psychosocial issues. The workers were asked to rate their pain on a 0 to 10 scale, with 0 being no pain and 10 being the worst ever. They also had to rate how much the pain interfered with their daily activities, also on a scale from 0 to 10. The workers' ability to function was measured using the Roland-Morris Disability Questionnaire. The workers were also assessed about how they reacted to their pain with the Pain Catastrophizing Scale and their expectations were measured with the Vermont Disability Prediction Questionnaire. Finally, the workers also completed the Fear-Avoidance Beliefs Questionnaire and the SF-36 v2 Mental Health Scale. One year after the study began, a follow-up interview was done, rating pain intensity and functional status.
The results of the study showed that of the 1,843 workers, 781 (42 percent) were prescribed at least one opioid prescription over the year, most of which were filled (694 workers). The prescriptions were filled by 59 percent in one quarter of the year (three month period), 15 percent in two quarters, 10 percent in three quarters and 16 percent for all four quarters.
Among the workers who took opioids for all four quarters, 39 percent saw their prescriptions increased in strength by 62 percent. Previous studies of opioid use also found similar results. The majority of long-time users (61 percent) did see stable prescription strengths or even lower ones. Of the nine patients that were found to have dramatically increased doses, only three reported meaningful improvement in pain and none of them had any meaningful improvement in function.
The researchers found that the greater the pain, the worse the physical function and the greater the severity of the injury. Interestingly, being Hispanic and seeing a chiropractor when the injury occurred resulted in lower opioid use. Nine workers were prescribed very high doses, enough to cause concern regarding other health issues that could result.
The authors of this study concluded that patients with acute back injuries don't usually end up taking opioids for pain control. Those who do, however, didn't - for the most part - experience any great relief in pain or function. Therefore, the authors suggest that it is necessary to do more studies on use of opioids for chronic non-cancer pain. As well, doctors who are prescribing opioids for this type of pain should be monitoring their patients for improvements and if none is seen, rather than increasing the dose, reevaluate if opioids are the appropriate treatment.
Gary M. Franklin, MD, MPH, et al. Opioid Use for Chronic Lower Back Pain. In The Clinical Journal of Pain. November/December 2009. Vol. 25. No. 9. Pp. 743 to 751.