The Centers for Disease Control and Prevention recently released the draft of a guideline for prescription of opioids by primary care physicians (PCP) for chronic pain.
Although PCPs are the primary targeted audience, I would encourage any physician who prescribes opioids to read the guideline as it presents a very useful overview of our current knowledge about these drugs as well as essential factors all prescribers, no matter the specialty, need to consider when deciding if an opioid is appropriate. It is only a draft but I doubt that the final version will be markedly different as there do not appear to be any significant errors in its recommendations.
The guideline is based on currently available research and carefully evaluates the quality of the evidence, so I was not surprised to find little new or unexpected information nor anything that should result in a significant change in good clinical practice when considering prescription of opioids for chronic pain. That said, there has been some controversy that the recommendations lean more toward avoiding misuse of opioids than alleviating pain. Overall, though, I believe that they are fair and are not unduly weighted in either direction.
Conventional wisdom challenged
The guideline committee found very little research demonstrating the benefits of opioids for the management of chronic pain—pain lasting more than 3 months or past the time of normal tissue healing. (I must admit that I find the latter definition problematic. The development of chronic pain in many cases is a complex mixture of physical, psychological, and environmental factors that as yet are poorly understood so I find focusing solely on the physical aspect is incorrect.) Guideline authors were unable to find any studies that compare the long-term benefits of opioid therapy to those of other treatments for chronic pain including non-opioid medications and non-pharmacologic treatments, giving lie to a widely held belief that opioids are always the optimal treatment for pain.
The draft also reports that many non-pharmacologic therapies have been found highly effective for the management of chronic pain, citing especially the benefits of cognitive behavioral therapy. With regard to non-opioid medications it notes that depending upon the type of pain, acetaminophen, the nonsteroidal anti-inflammatory drugs (NSAIDs), the tricyclic antidepressants and other serotonin-norepinephrine reuptake inhibitors, and the anticonvulsants can provide more effective analgesia than do the opioids.
The guideline enumerates the many problems that extended use of opioids may cause, most notably the development of opioid use disorder (the DSM-5 category covering abuse and addiction) and risk of overdose. Patients may overdose or do damage to their bodies using non-opioid analgesics such as NSAIDs (bleeding, cardiac problems) and acetaminophen (liver toxicity), however neither carry the risk of addiction or substance abuse.
|"...we still don't have a good estimate of exactly how many patients prescribed opioids for legitimate pain complaints develop opioid use disorder."|
The guideline highlights one of the problems that any physician prescribing opioids faces: how to identify patients at greatest risk for developing opioid use disorder. The only consistent risk factors reported in the literature are well known—a history of substance abuse, major depression, use of psychotropic medications, and younger age. The predictive results of the currently used screening instruments such as the Opioid Risk Tool (ORT) and Screener and Opioid Assessment for Patients with Pain-Revised (SOAPP-R) were found to be inconsistent and therefore of uncertain value in identifying potential abusers.
It also notes that we still don't have a good estimate of exactly how many patients prescribed opioids for legitimate pain complaints develop opioid use disorder.
Other major points in the draft also have been noted in many other guidelines on the use of opioids including avoiding the use of long-acting/extended release opioids for initial opioid therapy and the limited research demonstrating that they are more beneficial than short-acting/immediate release opioids despite the fact that their use is more likely to result in overdose deaths.
Importantly the draft guidance reiterates one of the cardinal rules for the management of chronic pain: that improvement of functioning is a goal equally as important as pain reduction and that determination of the benefits of any treatment for chronic pain must weigh both.
There are two points upon which I believe the guideline should be more complete and that I hope will be revised for the final iteration; one recommendation with which I disagree; and I have one major concern about the guideline as a whole.
The first two relate to prescribing opioids to patients taking benzodiazepines and the use of methadone. The guideline advises against prescribing opioids to benzodiazepine users citing the evidence that taking both classes of drugs together significantly raises the risk of overdose deaths. This is true but I believe that it should also cite the evidence that benzodiazepine use actually interferes with the analgesic effects of opioids, providing an additional reason why their concomitant use is generally contraindicated.
With regard to methadone, the guideline warns against its use because of the associated risk of QT prolongation and the high number of overdose deaths linked to the drug. There is a failure to note, however, that one of the major problems with methadone is that very few doctors are aware of its proper dosing as an analgesic and misprescribe it based on its use for opioid addicts where the required dosage usually much higher. The draft document does state that “only providers who are familiar with methadone’s unique risk profile and who are prepared to educate and closely monitor patients...should consider prescribing methadone for pain.” I would argue that the same statement should be true for prescribers of all opioids or, for that matter, for any drugs we prescribe.
|One problem "with methadone is that very few doctors are aware of its proper dosing as an analgesic and misprescribe it based on its use for opioid addicts..."|
I have a problem with the recommendation that urine drug screening (UDS) be used at the initiation of opioid treatment and at least once each year following that. I have no argument with this recommendation in itself although I do not believe most physicians’ offices are set up to obtain a valid UDS that is free of the risk of tainting in some manner by patients who are aware that their use/misuse of substances might be detected.
Of more concern, and the guidelines note this, is that there is no research yet to demonstrate that UDS reduces the risk of opioid use disorder, overdoses, or diversion of the drugs; its utility is essentially based on clinicians’ instincts that it should help avert these issues. Given the widespread use of UDS surveillance and the significant cost to practices who use it routinely, shouldn’t we have examined those beliefs by now?
My final concern is that some may consider the guideline to be a replacement for physician education on opioid prescribing. Guidelines are meant to provide updates on current states of knowledge and in no way to be a substitute for a base of knowledge that should be acquired during medical school, postgraduate training, and continuing medical education. Multiple studies have demonstrated that many, if not most physicians lack this educational foundation. No guideline can alleviate this deficiency; only more and better teaching can.
Centers for Disease Control. Guideline for prescribing opioids for chronic pain - United States, 2016. Available at www.regulations.gov/#!documentDetail;D=CDC-2015-0112-0002. Accessed January 2, 2016.