How Useful Are Patient Opioid Agreements and Urine Drug Testing?

When I lecture about opioid analgesics for chronic pain, I am often asked about the use of written patient opioid agreements (POAs) and urine drug testing (UDT). A few audience members are always surprised when I respond that although I have no objections to employing these tools, I never have used the former and rarely use the latter during my management of patients with chronic pain.

It is not that I am unaware of or unconcerned about the misuse of prescription opioids. The most recent information from the federal government’s Substance Abuse and Mental Health Services Administration’s Drug Abuse Warning Network indicates this continues to be a growing problem in the United States. The estimated number of emergency department (ED) visits for nonmedical use of opioid analgesics increased from 144,600 in 2004 to 305,900 in 2008-a 111% increase.¹ Furthermore, there is no sign that this problem is leveling off: there was a 29% increase in the number of ED visits from 2007 to 2008 alone.

By definition, opioids-unless they are stolen from a dispenser such as a pharmacy or obtained by forgery-must be prescribed by a health care professional, usually a physician. It therefore behooves us to seek out methods that will limit the non-therapeutic use of these medications.

When I prescribe an opioid, I discuss with the patient the importance of using the medication as prescribed. I also discuss the need to:

• Inform me if he or she is receiving other care, including medications for pain

• Inform me of any problems encountered with the medication, including lack of efficacy

• Avoid substances, both legal and illicit, that might interfere with the actions of the prescribed medications or interact with them in a hazardous manner

This discussion is not especially different from the one I have with patients for whom I prescribe non-opioid medications.

But why don’t I use POAs and UDT for patients with chronic pain who take opioids? Guidelines on the use of prescription opioids do suggest that written POAs and UDT might benefit some patients. However, there does not appear to be any firm evidence that these tools reduce the likelihood that opioids will be used in unintended ways.

In their joint guidelines for the Use Chronic Opioid Therapy (COT) in Chronic Noncancer Pain, the American Pain Society and the American Academy of Pain Medicine state that “clinicians may consider using a written COT management plan to document patient and clinician responsibilities and expectations and assist in patient education.”^2(p116) However, only weak support in the literature for doing this was found. Furthermore, while the guidelines cite provisions that might be included in a written plan, such as prescribing by only a single physician and random drug screens, they state that “there is insufficient evidence to guide specific recommendations on which provisions to include.^2(p117)

A recent extensive literature review of the value of POAs and UDT for patients with chronic pain also highlights the lack of support for employing them. Starrels and colleagues³ examined the literature and found only 11 articles that met their inclusion criteria of original research that addressed the use of a written POA or routine UDT for patients with chronic pain using opioids for at least 3 months. They also required that the studies include at least 50 subjects and that those studies were published in English, Spanish, or French.

Of 11 studies, 6 were conducted in pain clinics and 5 in primary care settings. Seven used both POAs and UDT, and 1 used only the latter. Of the studies that provided examples of the POAs that were employed, most included agreements that patients would not abuse illicit drugs or alcohol, would only receive opioid prescriptions from a single provider and pharmacy, and would not request refills before the previous prescription should have been completed. There was a great deal of variability regarding the frequency of UDT in the studies that used them. These tools were used regularly or randomly in 4 studies. Three others indicated their use at set times; additional use was left to the judgment of the treating physician.

In identifying opioid misuse, the studies employed a variety of criteria. Curiously, none used the DSM-IV criteria for opioid abuse or dependence. In the 4 studies that included a control group, there were reported reductions of 7% to 23% in opioid misuse when POAs and UDT were used. However, the reviewers considered the quality of 2 of these studies to be fair and the other 2 to be poor on the basis of study design and thus questioned their results.

The 7 remaining studies that used POAs and/or UDT offered a wide range of results; 3% to 43% of patients were found to have misused opioids. The range was similar in both the pain clinics and primary care settings. Again, the reviewers criticized the quality of these studies: 5 were rated as fair and 2 as poor. They found comparison of the studies to be difficult because of variations in patient population; for example, some excluded known substance abusers while others included them.

Apart from the lack of evidence supporting their use, is there any reason not to use POAs and UDT? Although their use does not appear to cause an overt harm, I think they may limit how one deals with questionable behavior by patients. Also, they may give health care providers a false sense of security that their use will significantly reduce or even eliminate the risk of the misuse of opioids. It is impossible to foresee every issue of concern that may arise. Thus, if an issue arises that is not covered by the POA, the physician can end up in a debate with the patient about the fairness of adding new restrictions. Of course, it is possible to include a statement in the POA that the physician has the right to add restrictions to address unforeseen circumstances. By doing so, however, we are (to some degree) back at square one in saying that the POA is a guide rather than a firm agreement.

One might choose to limit the use of POAs and UDT to suspected substance abusers or to those who are likely to misuse opioids. The Federation of State Medical Boards’ Model Policy for the Use of Controlled Substances for the Treatment of Pain states the following^4(pp6,7):

If the patient is at high risk for medication abuse or has a history of substance abuse, the physician should consider the use of a written agreement between physician and patient outlining patient responsibilities, including: urine/serum medication levels screening when requested; number and frequency of all prescription refills; and reasons for which drug therapy may be discontinued (eg, violation of agreement.

The problem with this recommendation is that unless the patient has a history of substance abuse, it is often difficult-if not impossible-to accurately determine the risk level for the misuse of opioids legitimately prescribed for the treatment of pain.

References:

References

1. Centers for Disease Control and Prevention (CDC). Emergency department visits involving nonmedical use of selected prescription drugs-United States, 2004-2008. MMWR. 2010;59:705-709.
2. Chou R, Fanciullo GJ, Fine PG, et al; American Pain Society-American Academy of Pain Medicine Opioids Guidelines Panel. Clinical guidelines for the use of chronic opioid therapy in chronic noncancer pain. J Pain. 2009;10:113-130. http://www.ampainsoc.org/pub/pdf/Opioid_Final_Evidence_Report.pdf. Accessed December 6, 2010.
3. Starrels JL, Becker WC, Alford DP, et al. Systematic review: treatment agreements and urine drug testing to reduce opioid misuse in patients with chronic pain. Ann Intern Med. 2010;152:712-720.
4. Federation of State Medical Boards. Model Policy for the Use of Controlled Substances for the Treatment of Pain. Dallas: Federation of State Medical Boards; 2004