AMSTERDAM – Opioids cannot be justified for the routine treatment for musculoskeletal pain because risks outweigh benefits, according to a detailed review of published studies presented at the European Congress of Rheumatology.
“There is very little evidence of benefit for the long-term management of nonmalignant pain, but very good evidence for harm,” reported Blair Smith, MD, head of the population health sciences division, University of Dundee (Scotland).
In the treatment of musculoskeletal pain, the goals are increased function and quality of life, rather than complete relief of pain, according to Dr. Smith. On this basis, opioids are not an appropriate routine therapy. He reported that pain relief is not well documented, while side effects such as sedation, dizziness, and constipation, are likely to be counterproductive to improved outcomes.
There is no absolute contraindication for opioids in the control of chronic musculoskeletal pain, but Dr. Smith’s summary of the data led him to conclude that they should be used judiciously and “only for carefully selected patients.”
Of the many studies he reviewed to draw this conclusion, one of the most recent was identified as the most persuasive. Published earlier this year, the SPACE study is “the first good-quality study of long-term opioid use” in patients with musculoskeletal complaints. It was negative.
“The pain intensity at the end of 12 months of treatment was slightly but significantly worse among those randomized to opioids,” reported Dr. Smith. “There was no difference in patient function, but there was an increased risk of adverse events.”
In the SPACE study, 240 patients with moderate to severe chronic back pain or hip or knee osteoarthritis were randomized to opioid or nonopioid pain management. In the nonopioid group, the first therapeutic step was acetaminophen, but medications could be changed, added, or adjusted within both groups to improve patient response.
At the end of 12 months, a lack of benefit on both pain control and functional improvement from opioids relative to nonopioid treatment was accompanied by a higher rate of adverse effects. This led the authors to conclude that opioids are not supported for musculoskeletal pain.
Not all the evidence argues against opioids for noncancer pain management, according to Dr. Smith, but he emphasized that those who support use of opioids do so for pain control only. They do not confirm an advantage for function and quality of life, which he suggested are the key endpoints. For example, a 2010 Cochrane review concluded from a systematic literature review that there is “weak evidence” for pain relief but inconclusive evidence of an improvement in functioning and quality of life.
Other investigators have drawn the same conclusion, according to Dr. Smith. He cited a statement from the International Association for Study of Pain that advises, “Caution should be used for prescribing opioids for chronic pain.” Although this statement was not specific to musculoskeletal pain, the IASP does specify that pain medications should be employed “to promote increased function and improved quality of life rather than complete relief of pain,” according to Dr. Smith.
Opioid prescriptions for chronic pain have been increasing in Europe as they have in the United States, but Dr. Smith indicated that opioids, if used at all, should be prescribed for very short periods and for very specific goals, particularly improvement in function.
“Probably most important for my [primary care] colleagues, patients prescribed opioids should be evaluated early and frequently to gauge benefit,” Dr. Smith said. Although he believes pain control is an important and worthwhile goal, it must be approached within the context of improved well-being rather than as an isolated endpoint.