The Comorbidity of Chronic Pain and Mental Health Disorders: How to Manage Both
One of the most successful treatment models for comorbid pain and mental health disorders is a program based on the biopsychosocial model, which takes into account physical, mental health, and social issues. There is a great deal of evidence showing the effectiveness of this treatment model for musculoskeletal pain, temporomandibular disorder (TMD), headaches, and widespread pain and fibromyalgia.1
One of the earliest biopsychosocial treatment programs—functional restoration—was designed to address the problems encountered by patients with chronic occupational musculoskeletal disorders. Functional restoration is implemented by an interdisciplinary team of healthcare professionals operating together to achieve a unified treatment plan that is individualized to patient needs. The team is led by a supervising physician who coordinates patient care with an emphasis on return to function.
There are two main components to a functional restoration program: a quantitatively directed exercise program and a multimodal disability management program. The quantitatively directed exercise program is based on the sports medicine principle of working through pain rather than avoiding it. Physical and occupational therapists work with patients to reactivate deconditioned muscles, joints, and ligaments using active exercise treatments rather than passive pain-reducing modalities.2 The multimodal disability management program addresses the psychosocial issues of the patient with chronic pain. Mental health professionals lead group and individual counseling sessions of cognitive-behavioral therapy based on a crisis intervention model. The case management department assists the patient in navigating the workers’ compensation and disability insurance systems and also assists with vocational reintegration so patients can successfully return to employment after treatment.2
A great many studies have demonstrated the effectiveness of interdisciplinary rehabilitation for the treatment of chronic spinal and musculoskeletal pain.3-16 The majority of interdisciplinary rehabilitation studies have focused on patients with chronic spinal and musculoskeletal pain (disabled for more than 4 months), but the functional restoration model also has shown success in treating acute and subacute musculoskeletal pain.17
The success of interdisciplinary rehabilitation in the treatment of musculoskeletal pain has prompted its expansion into the treatment of other pain conditions. In the treatment of headaches, interdisciplinary programs usually include stress management training, relaxation exercises, biofeedback treatments, and education about headache triggers and medication compliance.18-20 In some cases, physical therapy and exercise are part of the treatment program, especially in tension-type headaches. In addition, decreases in depressive and anxious symptoms have been noted, and patients also may show improvements in absences from work and headache-related disability.18-22
In the management of TMD, interdisciplinary programs usually include cognitive-behavioral skill training, biofeedback, stress education, and relaxation training. Patients demonstrate long-lasting improvements in pain intensity, pain-related disability, and mandibular function.23-25 A systematic review of TMD treatment programs also found evidence for the effectiveness of exercise, postural training, relaxation, and biofeedback in the treatment of TMD.26
In addition, functional restoration programs have been applied to conditions such as chronic widespread pain and fibromyalgia, with results similar to those found in musculoskeletal pain patients.27 Other interdisciplinary programs also have shown success in treating fibromyalgia.28,29 Finally, interdisciplinary programs have shown some preliminary success in treating neuropathic pain conditions such as nerve injury and neuropathy,30,31 but further study is needed in this area.
Overall, treatments for chronic pain and mental health disorders based on the biopsychosocial model have shown consistently high success rates for a variety of conditions.32
The high comorbidity between chronic pain and psychiatric disorders often necessitates the incorporation of psychotropic medication in chronic pain management. Additionally, the use of psychotropic medications is reinforced by their effectiveness as adjuvant analgesics. Psychotropic medication also modifies opioid doses, thus preventing, in part, dependency.
Selecting the Right Medication
Specific issues that need to be considered when prescribing any medication are:
- Cause of patients’ chronic pain and their complaints (see Table 1)
- Comorbidity of chronic pain with other illnesses and/or psychiatric condition
- History of patients’ medication pertinent to complaints, including abuse, dependence, compliance, and side effects
Opioids are used as a second-line treatment for moderate to severe noncancer pain when patients do not respond to acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs), experience pain-related functional impairment, or have diminished quality of life (see Table 2, page 63).33-36 Before prescribing such medications, a thorough assessment of risk for interaction between potential opioid and concurrent psychiatric medication, as well as drug abuse history, must be diligently conducted.37 Noble et al conducted a meta-analysis of long-term opioid management of chronic noncancer pain. Many patients discontinued opioid treatment because of adverse effects (8.9% to 22.9%) or insufficient pain relief (5.8% to 10.3%) depending on mode of consumption (oral, transdermal, or intrathecal).38 Long-term opioid medication, with various analgesic effects, results in pain relief. Inconclusive results were found for the effect of opioid medication on quality of life and functioning. For neuropathic pain, opioids were reported to be more effective than placebo in an intermediate-term study.39
Opioids may be classified as having weak (eg, codeine, hydrocodone, and oxycodone) or strong (eg, morphine, fentanyl, and hydromorphone) analgesic properties; thus, the type of opioid prescribed depends on the patient’s pain intensity. There is evidence of oxymorphone efficacy in controlling and reducing pain compared with placebo in chronic low back pain.40,41 Propoxyphene and dextropropoxyphene are not recommended because of their low therapeutic-to-toxicity ratios.42