Patient Selection and Risk Stratification
Before initiating Chronic Opioid Therapy (COT), APS/AAPM recommends that clinicians should conduct a history, physical examination and appropriate testing, including an assessment of risk of substance abuse, misuse, or addiction (strong recommendation, low-quality evidence).
Clinicians may consider a trial of COT as an option if chronic non-cancer pain (CNCP) is moderate or severe, pain is having an adverse impact on function or quality of life, and potential therapeutic benefits outweigh or are likely to outweigh potential harms (strong recommendation, low-quality evidence).
A benefit-to-harm evaluation, including a history, physical examination, and appropriate diagnostic testing, should be performed and documented before, and on an ongoing basis during, COT (strong recommendation, low-quality evidence).
Proper patient selection is critical and requires a comprehensive benefit-to-harm evaluation that weighs the potential positive effects of opioids on pain and function against potential risks. Thorough risk assessment and stratification is appropriate in every case. This approach is justified by estimates of aberrant drug-related behaviors, drug abuse, or misuse in patients with CNCP, which range from 0% to 50% depending on the population evaluated and methods used to define and identify these outcomes. Risk stratification pertaining to outcomes associated with the abuse liability of opioids—misuse, abuse, addiction and diversion—is a vital, but relatively undeveloped, skill for many clinicians. However, all clinicians prescribing opioids should be knowledgeable about risk factors for opioid abuse and methods for assessing risk. Assessment of risks for opioid-associated adverse effects also should be performed, given their high prevalence.
Thorough History and Physical Examination
A thorough history and physical examination, including an assessment of psychosocial factors and family history, is essential for adequate risk stratification. Implicit in the recommendation to conduct a comprehensive benefit-to-harm analysis is the recognition that an opioid trial may not be appropriate. Clinicians should obtain appropriate diagnostic tests to evaluate the underlying pain condition, and should consider whether the pain condition may be treated more effectively with nonopioid therapy rather than with COT. For example, COT generally would not be appropriate before a trial of an anticonvulsant for trigeminal neuralgia, a disease-modifying antirheumatic drug for rheumatoid arthritis, a corticosteroid for polymyalgia rheumatica, or various abortive and prophylactic therapies for migraine headache.
Evidence on Methods is Limited
Reliable evidence on methods to accurately assess the potential benefits of COT is limited. However, randomized trials that demonstrate the benefits of COT are most applicable to patients with moderate or more severe pain who have not responded to nonopioid therapies. Presence of poorly-defined pain conditions, a likely somatoform disorder, or unresolved compensation or legal issues may predict poorer response to all therapies, including COT. Although neuropathic and non-neuropathic pain conditions appear in general to respond similarly to COT. Evidence that demonstrates the efficacy of COT for conditions with strong psychosocial contributors such as some types of chronic low back pain, daily headache, and fibromyalgia is sparse. There is insufficient evidence to recommend use of an intravenous opioid trial to predict likelihood of benefit from COT.
Personal History is Predictive of Abuse
The factor that appears to be most strongly predictive of drug abuse, misuse, or other aberrant drug-related behaviors after initiation of COT is a personal or family history of alcohol or drug abuse. Younger age and presence of psychiatric conditions are also associated with aberrant drug-related behaviors in some studies. Pre-existing constipation, nausea, pulmonary disease, and cognitive impairment probably predict risk for opioid-related adverse effects, although no studies have adequately evaluated the utility of these factors for use in risk stratification.
Consider a Trial of COT for CNCP
Clinicians should consider a trial of COT for CNCP when potential benefits are likely to outweigh risks, and there is no alternative therapy that is likely to pose as favorable a balance of benefits to harms. COT in this context requires intensive structure, monitoring, and management by professionals with expertise in both addiction medicine and pain medicine and should be undertaken only if risks can be adequately managed. The selection of patients between these two extremes requires careful assessment and characterization of patient risk, and structuring of care to match risk. In patients with a history of substance abuse or a psychiatric comorbidity, this may require assistance from persons with expertise in managing pain, addiction or other mental health concerns, and in some cases opioids may not be appropriate or should be deferred until the comorbidity has been adequately addressed.
Screening Tools Can Be Helpful
Screening tools that assess the potential risks associated with COT based on patient characteristics are likely to be helpful for risk stratification, although more validation and prospective outcome studies are needed to understand how their use predicts and affects clinical outcomes. Tools that appear to have good content, face, and construct validity include the Screener and Opioid Assessment for Patients with Pain (SOAPP) the revised SOAPP (SOAPP-R), the Opioid Risk Tool (ORT), and the Diagnosis, Intractability, Risk, Efficacy (DIRE) instrument. DIRE is clinician-administered and is designed to assess potential efficacy as well as harms. The SOAPP Version 1, SOAPP-R and ORT are patient self-report questionnaires that assess risk of aberrant drug-related behaviors.
1Chou R et al. Clinical Guidelines for the Use of Chronic Opioid Therapy. J Pain. 2009.