Beyond chronic pain: How best to treat psychological comorbidities
When chronic pain is accompanied by disturbances in sleep, a psychiatric disorder, or substance misuse, a single agent with multiple symptom targets may be the best place to start.
The opioids tramadol and methadone are recommended as third-line therapy, along with nonopioid medications such as cannabinoids, lamotrigine, topiramate, and valproic acid.27
Use a comprehensive pain scale, such as the Brief Pain Inventory, to assess the pain of any patient with a history of a substance-related disorder rather than asking him or her to rate the pain level on a general Likert-type scale.15
Long-acting opioids, such as sustained-release morphine, oxycodone, or fentanyl patch, are preferable to short-acting immediate-release opioids, which have a higher addictive profile because of their fast onset of action.15 Keep in mind, however, that long-acting opioids also have the potential for abuse, and patients taking them must be carefully monitored, as well.
Nonpharmacologic therapy often helps, too
Evidence suggests that even the most potent drugs significantly decrease pain in only about half of those taking them.39 And whether or not adequate pain relief is achieved, patients with the constellation of pain and sleep, mood, anxiety, and/or substance disorders can benefit from nonpharmacologic interventions, as well. Let patients know that CBT, in particular, has been shown to have a positive effect on psychological function and comorbid psychological disorders, particularly when it is combined with pharmacologic therapy.40 In addition, other nonpharmacologic treatments, including biofeedback41-44 and meditation,45-47 have shown preliminary value in managing pain.
Further research is needed to understand the effectiveness of CBT in the management of chronic pain; however, it appears that CBT may have a positive effect on psychological functioning and comorbid psychological disorders.
The bottom line: Don’t overlook mood, anxiety symptoms in pain patients
In epidemiological studies of chronic pain, it is apparent that sleep, depressive, substance abuse/dependence, and anxiety syndromes often occur together, which supports the necessity of considering psychosocial dynamics to understand pain. Although there has been some inconsistency observed across findings (eg, Romano and Turner),48 clarifying the relationships amongst these disorders may be an avenue for future research. The literature to date suggests that mood- and anxiety-related symptoms should not be overlooked in pain patients, as there is a negative effect on prognosis when these disorders co-occur.6
Treatment should be based on individual patient factors, such as presenting symptoms and potential for drug side effects. Some pharmacologic agents have been shown to be effective in treating several symptoms of this pyramid. Such drugs offer the best success and relapse rates, and reduce the likelihood of drug interactions. CBT appears to offer added benefits, especially if combined with pharmacology. However, few controlled trials have been conducted in this area and further research is required to appropriately guide clinical management.
CORRESPONDENCE
Martin A. Katzman, MD, FRCPC, START Clinic for Mood and Anxiety Disorders, 32 Park Road, Toronto, Ontario, Canada M4W 2N4; mkatzman@startclinic.ca
