Approaches to treatment decisions for psychiatric comorbidity in the management of the chronic pain patient

Pain Management: A Fundamental Human Right

This article surveys worldwide medical, ethical, and legal trends and initiatives related to the concept of pain management as a human right. This concept recently gained momentum with the 2004 European Federation of International Association for the Study of Pain (IASP) Chapters-, International Association for the Study of Pain- and World Health Organization-sponsored "Global Day Against Pain," where it was adopted as a central theme. We survey the scope of the problem of unrelieved pain in three areas, acute pain, chronic noncancer pain, and cancer pain, and outline the adverse physical and psychological effects and social and economic costs of untreated pain. Reasons for deficiencies in pain management include cultural, societal, religious, and political attitudes, including acceptance of torture. The biomedical model of disease, focused on pathophysiology rather than quality of life, reinforces entrenched attitudes that marginalize pain management as a priority. Strategies currently applied for improvement include framing pain management as an ethical issue; promoting pain management as a legal right, providing constitutional guarantees and statutory regulations that span negligence law, criminal law, and elder abuse; defining pain management as a fundamental human right, categorizing failure to provide pain management as professional misconduct, and issuing guidelines and standards of practice by professional bodies. The role of the World Health Organization is discussed, particularly with respect to opioid availability for pain management. We conclude that, because pain management is the subject of many initiatives within the disciplines of medicine, ethics and law, we are at an "inflection point" in which unreasonable failure to treat pain is viewed worldwide as poor medicine, unethical practice, and an abrogation of a fundamental human right.

The Coexistence of Neuropathic Pain, Sleep, and Psychiatric Disorders

The diagnosis and treatment of neuropathic pain may be complicated by comorbid conditions such as sleep disturbances, depression, and anxiety. The interrelationship between the index neuropathic pain state and these comorbidities is complex: comorbid conditions exacerbate pain, and in turn, pain exacerbates the comorbid conditions. Because comorbidities can negatively impact response to pain treatment, healthcare providers should assess comorbidities as part of the diagnostic work-up, and management strategies should be designed to treat the whole patient, not just the pain. Theoretically, therapies that not only reduce pain, but also improve sleep and reduce anxiety and depression can provide multiple benefits without the risk of increased side effects inherent in combination therapy. Anticonvulsants and antidepressants have demonstrated efficacy in improving neuropathic pain and positively impacting comorbid sleep and mood disturbances. Novel anticonvulsants that can address one or more comorbidities in addition to pain may represent viable treatment options for patients with neuropathic pain.

New perspectives on the management of diabetic peripheral neuropathic pain

Peripheral neuropathy affects about 30% of people with diabetes mellitus. Between 16% and 26% of diabetes patients experience chronic pain. This may be referred to as diabetic neuropathic pain (DNP) or diabetic peripheral neuropathic pain (DPNP). Minimum requirements for diagnosis of DPNP should include assessment of pain and symptoms and neurological examination, with the accent on sensory examination. Given that depression and other co-morbidities are commonly associated with this condition, a broad approach to management is essential. Lifestyle intervention and optimisation of glycaemic control are recommended as initial steps in management. An evidence-based treatment algorithm for DPNP has been proposed, recommending initial use of either a tricyclic antidepressant, selective serotonin noradrenaline re-uptake inhibitor or alpha-2-delta agonist, depending on patient co-morbidities and contra-indications. Addition of an opioid agonist may be required in the event of inadequate pain control. Irrespective of which treatment is offered, only about one third of patients are likely to achieve more than 50% pain relief. Further research to improve the diagnosis and management of DPNP is needed.

The Association Between Psychopathology and Placebo Analgesia in Patients with Discogenic Low Back Pain

BACKGROUND

Chronic low back pain patients have a high rate of psychopathology, comprised mainly of depression, anxiety, and high levels of neuroticism. We previously found that psychopathology is associated with increased placebo analgesia in this patient group.

OBJECTIVE

To better understand this finding in the context of other known predictors of placebo response (such as expectations for relief), we performed a detailed analysis of expectations and other possible covariates.

DESIGN

We conducted a double-blind, placebo-controlled, randomized, crossover-designed trial of intravenous morphine vs. placebo in 60 subjects with chronic low back pain and discogenic abnormalities. Patients were stratified into three groups of psychiatric symptom severity (Low, Moderate, and High), based on composite scores on depression, anxiety for pain, and neuroticism scales. Subjects were given intravenous morphine and placebo in random order on separate visits, and completed serial pain ratings over 3 h at each session.

RESULTS

With 20 subjects per group, there were small, but significant differences between groups in baseline pain ratings. No differences were found between groups in age, gender, and radicular pain. Patients with low psychological symptomatology reported 7.7% total pain relief with placebo compared with 23.4% in the Moderate group and 23.5% in the High group (P < 0.05). Expectations were not significantly different between groups, but in the High group expectation levels predicted placebo analgesia (P < 0.001). Neuropathic pain quality was also a predictor (P < 0.05).

CONCLUSIONS

This study indicates that high and moderate levels of psychopathology are associated with heightened placebo analgesia in chronic low back pain patients. Expectations were only an influence in the high psychopathology group, and neuropathic pain affects placebo responses. These findings have implications for future research characterizing placebo responders.

Chronic widespread pain and psychiatric disorders in veterans of the first gulf war

More than 10% of the 700,000 American troops who served during the first Gulf War (GW) are receiving treatment for a constellation of diffuse and frequently poorly defined medical and psychiatric symptoms that have been designated the GW syndrome by both clinicians and the popular media. The current clinical consensus is that the symptoms reported in GW veterans are the sequela of combat and other stressful events that have been identified in the veterans of other wars and armed conflicts. Chronic diffuse pain is one constellation of symptoms commonly reported in GW veterans. Research has confirmed a close bimodal relationship between chronic pain and psychiatric symptoms. Investigators are now exploring the efficacy of treatment approaches that address the close relationship between chronic pain and mental illness in this challenging patient population.

The association between negative affect and opioid analgesia in patients with discogenic low back pain

Comprised mainly of depression, anxiety, and high neuroticism, psychopathology diminishes the effectiveness of many chronic pain treatments. But, it is not known if it is associated with diminished opioid analgesia in patients with chronic, noncancer pain. We tested the hypothesis that psychopathology diminishes opioid analgesia in patients with discogenic low back pain in 60 patients not on opioids in a double blind, placebo controlled, random crossover designed trial. Patients were stratified into three groups of psychological symptom severity (LOW, MOD, and HIGH), based on composite scores on depression, anxiety for pain, and neuroticism scales. Subjects were given intravenous morphine (4-6mg dosed by ideal body weight) and placebo in random order on separate visits, and completed serial pain ratings over three hours at each session. With 20 subjects per group, there were nonsignificant differences between groups in the distribution of age, gender, baseline pain (avg. 6.1/10), radicular pain, and morphine dose (5.0mg). For morphine analgesia, using a total pain relief calculation (TOTPAR), the LOW group had 65.1% TOTPAR vs. 41.0% in the HIGH group, P=.026. For placebo analgesia the LOW group had 7.7% TOTPAR vs. 23.5% in the HIGH group, P=.03. A morphine minus placebo analgesia calculation revealed 59.2% TOTPAR in the LOW group vs. 21.7% in the HIGH group, P=.0001. High levels of psychopathology are associated with diminished opioid analgesia in patients with discogenic low back pain. These results have implications for the prescription of oral opioids to patients with chronic low back pain and psychopathology.

Chronic pain and comorbid depression

For patients with chronic pain, the experience of pain is intimately linked with psychologic distress. Epidemiologic studies indicate that depression is a common comorbidity accompanying chronic pain states. Longitudinal studies also suggest that depression can predict the emergence of chronic pain in selected populations. Emerging evidence suggests numerous pathophysiologic mechanisms that underlie the coexistence of depression and chronic pain states. Comorbid depression can complicate the presentation, clinical course, and response to treatment of patients with chronic pain. The literature reviewed herein focuses on treatment approaches applicable to chronic, nonmalignant pain states predominantly. Although antidepressants offer advantages in simultaneously producing pain relief and mitigating depression, not all antidepressants share equal efficacy; those with noradrenergic and serotonergic influences seem to fare better than agents with single neurotransmitter influences. Treatment of depression may be essential to fully enlist the patient with chronic pain in comprehensive pain management and rehabilitative approaches. Management plans of patients with chronic pain can be designed with specific individual patient needs in mind, and may involve concurrent use of antidepressants, analgesics, and psychotherapeutic approaches.

The psychology of pain

Emotional and evaluative issues are very important in the evaluation and treatment of pain. Treating the physical pain alone can leave these issues unresolved, and possibly exacerbate them through reinforcement. Understanding the impact of fear, expectations, and attention can help physicians deal more effectively with acute pain. Psychological issues are particularly prominent in chronic pain. Though acute care physicians may not be treating these psychological conditions, they can help by referring patients to the appropriate psychological or multidisciplinary setting.

Psychiatry in chronic pain: a review and update

As the field of pain management nears the halfway point of the Congressionally declared "Decade of Pain Control and Research," the prevalence of chronic pain and disability related thereto continue to escalate. In the context of rising costs and suffering associated with persistent pain worldwide, the chronic pain research community has increasingly recognized and investigated the role of the cognitive and affective dimensions of pain. In this paper, the authors review psychologic aspects of pain, psychopathology in chronic pain syndromes, suicidality in this population, and the use of psychotropic medications for treatment in these patients. Where possible, the authors have outlined limitations of previous research in these areas, and have highlighted and described recent studies that have addressed these perceived shortcomings. The role of the psychiatrist in the treatment of patients with chronic pain is reviewed.

Illicit opioid use in Canada: comparing social, health, and drug use characteristics of untreated users in five cities (OPICAN study)

Most of the estimated 125,000 injection drug users (IDUs) in Canada use illicit opioids and are outside treatment (i.e., methadone maintenance treatment). Empirical data suggest that illicit opioid users outside treatment are characterized by various health and social problem characteristics, including polydrug use, physical and mental morbidity, social marginalization, and crime. Although required for evidence-based programming, systematic information on this specific substance-user population is sparse in Canada to date. This article presents and compares key characteristics of population of illicit opioid users outside treatment in five cities across Canada (OPICAN cohort). Overall, the majority of OPICAN participants regularly used both a variety of illicit opioids and cocaine or crack, reported physical and mental health (e.g., mood disorder) problems, lacked permanent housing, were involved in crime, and had their "ideal" treatment not available to them. However, key local sample differences were shown, including patterns of heroin versus prescription opioid use and levels of additional cocaine versus crack use as well as indicators of social marginalization. Illicit opioid user population across Canada differ on key social, health, and drug use indicators that are crucial for interventions and are often demonstrated between larger and smaller city sites. Differentiated interventions are required.

Biopsychosocial pain medicine and mind-brain-body science

This article reviews how emotions, behavior, and psychiatric comorbidity influence the course and outcome of chronic pain disorders and addresses methods of identifying and managing these problems in clinical practice. Successful medical rehabilitation for patients with chronic pain requires (1) appreciating the effects of biopsychosocial factors in the onset, course, and outcomes of pain disorders; (2) understanding neurobiologic mechanisms linking mind, brain, and body in the functions of pain perception and modulation; and (3) being able to review critically and use selectively the plethora of new medications and interventional technologies that are proposed in the literature. Deficits in these skills now are recognized as hazardous to the public health so that medical school education and post residency training in pain medicine is now mandatory in some states.

A case-matching study of the analgesic properties of electroconvulsive therapy

OBJECTIVE

Chronic pain improves with electroconvulsive therapy (ECT), yet few case reports account for treatment of comorbid major depression, a significant confounder of the analgesia of ECT. This study reports on the analgesia of ECT, controlling for treatment of depression.

METHODS

This is a case-matching study comparing outcomes of inpatients with chronic pain and major depression in a multidisciplinary pain treatment unit treated with ECT and medications (cases) with those of inpatients treated with medications only (controls). Both groups received the same behavioral and pharmacological treatments for depression and chronic pain. Outcome measures included 0-10 pain rating scales and the Montgomery-Asberg Depression Inventory. Patients were matched on sex, age within 5 years, admission date within 6 months, psychiatric diagnoses, and, as much as possible, on race and pain syndrome diagnosis. Percentage changes in depression scores and pain scores were calculated from the beginning to the end of admission.

RESULTS

There were nonsignificant differences in demographics, except in the proportion married. Twenty-five of 28 ECT patients were matched. Depression improvements were similar between cases and controls (55.9% vs 40.5%). Despite higher initial pain (8.1 vs 6.9 on a 10-point scale), the ECT group had less final pain (3.4 vs 5.5). The ECT group had a 59.8% drop in pain versus a 15.8% drop in the control group, P > 0.01.

CONCLUSIONS

ECT has analgesic properties independent of its improvement of depression in patients with chronic pain and major depression. Improvements in depression were similar, while there was a significantly greater improvement in pain with ECT. The lower post-ECT treatment pain scores suggest a specific analgesic effect of ECT.

Comorbidities in Chronic Neuropathic Pain

Neuropathic pain arises from a lesion or dysfunction within the nervous system; the specific mechanisms that elicit neuropathic pain symptoms are the subject of ongoing research. It is generally acknowledged that neuropathic pain is extremely difficult to treat, and a major factor impacting outcomes is the presence of comorbidities such as poor sleep, depressed mood, and anxiety. Patients who suffer from chronic pain experience difficulties in initiating and maintaining sleep. Sleep deprivation has been associated with a decreased pain threshold, muscle aches, and stiffness in normal volunteers. The interrelationship of these factors is complex: Many chronic pain patients are depressed and anxious; sleep deprivation can lead to anxiety; and depression can be both the cause and the result of sleep disturbances. Thus, physicians must evaluate all aspects of pain, sleep, and mood in chronic pain patients. Several instruments have been developed to aid physicians in gathering qualitative and quantitative information from chronic pain patients. This triad of chronic pain, sleep disturbances, and depression/anxiety must be fully addressed if the patient is to be restored to optimal functionality. A multidisciplinary team approach allows for treatment of the whole patient. Nonpharmacologic interventions include relaxation therapy, sleep restriction therapy, and cognitive therapy. Strategies for pharmacologic interventions should attempt to maximize outcomes by employing, where possible, agents that address both the pain and the comorbidities. In this way, functionality may be restored and the patient's quality of life improved.

Unmet needs in the management of neuropathic pain

Neuropathic pain is a challenging condition to treat. It is heterogeneous in nature and largely resistant to treatment with commonly prescribed analgesics. Current management strategies fail to achieve adequate or satisfactory pain relief in a high proportion of patients. The four main reasons that treatments for neuropathic pain fail are: inadequate diagnosis and a lack of appreciation of the mechanisms involved; insufficient management of comorbid conditions; incorrect understanding or selection of treatment options; and the use of inappropriate outcomes measures. These unmet needs in the current management of neuropathic pain are reviewed in this article. The review focuses on the need for a methodical and mechanistic approach to diagnosis, and a flexible, interdisciplinary approach to treatment of neuropathic pain conditions, in order to improve pain relief and quality of life in patients with neuropathic pain.

Evolving role of the neurologist in the diagnosis and treatment of chronic noncancer pain

The neurologist has become increasingly involved in the multidisciplinary treatment of patients with chronic noncancer pain (CNP). Chronic noncancer pain affects a diverse patient population with multiple underlying diagnoses and associated therapies. Following the model of the American Board of Anesthesiology and the American Society of Anesthesiologists for practice guidelines and subspecialty requirements, neurologic pain management is now recognized as a subspecialty of neurology by the American Academy of Neurology and the American Board of Psychiatry and Neurology. Current basic and clinical research into the neuropathology, neurophysiology, neurochemistry, and neuropharmacology of chronic pain continues to expand diagnostic and therapeutic options. Informed regulatory agencies and professional organizations such as the American Academy of Neurology recognize the undertreatment of patients with CNP and provide clear recommendations to help neurologists in the ethical and effective treatment of patients with pain. Improved education of neurologists, other health care professionals, patients, and the media about evolving standards of pain care and therapy will produce a more supportive environment for the compassionate and ethical treatment of patients with CNP.

Assessment and treatment of comorbid psychiatric disorders in opioid-dependent patients

The purpose of this article is to provide a review of the prevalence, assessment, and treatment of common psychiatric disorders found among patients with opioid dependence. Dependence on opioids can include both persons who are physically dependent on opioids and persons who fulfill the criteria for a syndrome of opioid dependence, such as that found in the Diagnostic and Statistical Manual, fourth edition (DSM-IV). The latter grouping of persons typically abuse illicit opioids, and prevalence of comorbid conditions and approaches in diagnosis and treatment have been studied in these patients. High rates of other psychiatric disorders--both other substance-use disorders as well as non-substance-use psychiatric disorders--have been reported. The most common non-substance-use psychiatric disorders are depressive, anxiety, and personality disorders. When evaluating and planning treatment of opioid-dependent patients with concurrent psychiatric symptoms, it is important to determine if such symptoms are independent of the substance use or substance induced. In the former case, treatment should follow routine clinical practice, whereas in the latter case, treatment stability in substance use should be the first therapeutic step. The presence of a pain condition can further complicate assessment and treatment, as either pain itself or treatments used for pain may produce symptoms that overlap with psychiatric disorders.

The psychopharmacologic treatment of depression and anxiety in the context of chronic pain

Chronic pain afflicts millions of people, commonly causing depression and anxiety. These conditions must be treated to achieve a good functional outcome from pain treatment. Selective serotonin reuptake inhibitors, tricyclics, and newer antidepressants effectively treat both depression and selected anxiety disorders. Antidepressants with noradrenergic and serotinergic activity, and anticonvulsants, which may also stabilize mood, are effective in neuropathic pain. Other medications have limited but important pharmacotherapeutic roles.

Psychiatry has much to offer for chronic pain

OBJECTIVE

The objective of this study was to make an argument in favour of the inclusion of psychiatrists on chronic pain clinic teams.

METHOD

The argument takes the form of answers to four central questions: (i) does pain involve an emotional experience; (ii) do psychiatric disorders accompany chronic pain; (iii) can psychiatric disorders present as chronic pain; and (iv) which patients present to pain units, and what do we know of their personalities?

RESULTS

The affirmative case was substantiated in respect of the first three questions. In examining the last question, evidence indicates that patients who present to chronic pain units frequently have personality features that make assessment and therapy difficult.

CONCLUSIONS

Psychiatry is the field of medicine where practitioners have the most experience with emotional states and personality, and is the only field where they have specialized skills in the diagnosis and treatment of psychiatric disorders. Psychiatry has much to offer in chronic pain management and chronic pain management teams should include a psychiatrist. This conclusion has resourcing and training implications.

Treatment planning in pain medicine. Integrating medical, physical, and behavioral therapies

This article addresses a systematic approach to the treatment of chronic pain. The first section presents a biopsychosocial model of pain. The second section presents an application of the biopsychosocial approach to the clinical assessment and management of clinical cases with chronic pain.