Pain is one of the most complex of human experiences. It is the most common reason for which patients seek medical care. More than 80% of all physician visits are due to pain. Pain accounts for over $70 billion annually in health care costs and lost productivity. It is defined by the International Association for the Study of Pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage.” Accordingly, the perception of pain is not only a sensory experience, but also an emotional experience. It is important to distinguish between acute and chronic pain. The distinction between the two is not simply a matter of duration: (1) Acute pain is biologically useful; it serves as the body’s alarm of an underlying medical condition, whereas chronic pain loses this function. (2) The etiology of acute pain is almost always identifiable, whereas the complex interaction of physical and emotional factors in chronic pain make the etiology murky. (3) Cure and relief are almost always attainable in acute pain, but is often not possible with chronic pain; the goal in chronic pain treatment is to improve functionality. (4) Acute pain may lead to anxiety, whereas chronic pain is often associated with depression.
The first psychological model of chronic pain was the psychodynamic approach, which emphasized the psychological etiology of pain. Freud viewed pain as a symptomatic expression of an unconscious conflict seeking awareness. In 1965, Melzack and Wall revolutionized the way we think about pain with their “gate control” theory. For the first time, pain theory incorporated higher brain functions such as cognition and affect. The theory postulated the existence of a “spinal gate” in the dorsal horn of the spinal column, which modulates transmission cells influenced by inhibitory and facilitative fibers. Quite significantly, the theory postulated that cognitive and affective states can help open or close the gate. Although the theory has been revised due to new physiological discoveries, its basic premises remain.
Behavioral models, particularly operant conditioning, proposed by William Fordyce in the 1970s became popular. Fordyce proposed that the behavioral expression of pain, pain behavior, is the result of positive and negative reinforcers from the patient’s environment such as social reinforcement from family and friends, medications from physicians, financial incentives, or avoidance of activities. Subsequently, cognitive-behavioral models of pain became more popular, and remain the prevailing theory with regard to the assessment and treatment of chronic pain. The cognitive—behavioral model theorizes that the experience of pain is a reciprocal interaction of thoughts, feelings, physiology, and behavior.
The traditional medical model of chronic pain was that pain had either a physical basis or a psychological one. It is now well accepted that chronic pain is the end product of physiological, psychological, and social processes. These biopsychosocial determinants of chronic pain interact with one another: Neurophysiologies responses to noxious stimuli can trigger psychologies responses, whereas psychologies states such as depression or anxiety can affect the neurophysiologies system by enhancing or inhibiting the transmission of noxious signals. Social factors such as stress, environments reinforcers of pain (such as an overly attentive spouse), or financial compensation (such as through disability or litigation) can significantly influence a patient’s perception of pain. Many patients with chronic pain, particularly if pain resulted from an accident at work, will go on disability because they cannot or will not return to work. The disability system, however, often works against the best interests of the patient and the goals of pain management by offering compensation comparable to work, by promoting activity restrictiveness, by leading to extensive delays in medical and psychological authorizations, and by the not offering light duty work or trial return-to-work periods.
The most prevalent psychological characteristic of chronic pain patients is depression. Depression and chronic pain occur together so frequently that it is often difficult to determine whether the depression is a precipitant of the pain or a consequence of living with intractable pain. Levels of depression can range from minor mood state disturbances to major clinical depressions with active suicidal ideation. Other characteristics of patients with “chronic pain syndrome” include increased dependency on others, increased illness behaviors (such as grimacing), overreliance on medications, increased health care utilization, and family dysfunction (spouses may display clinically significant levels of emotional distress).
The multidisciplinary evaluation and treatment approach to the patient suffering with chronic pain is widely practiced and considered to be the standard of care. The psychological evaluation and assessment of chronic pain patients has evolved from unidimensional to multidimensional models. Since the formation of the first multidisciplinary pain center in 1961 by John Bonica at the University of Washington, there are over 350 such centers. A multidisciplinary pain center is a facility in which comprehensive treatment is provided by a team of health care professionals including physicians, psychologists, physical therapists, occupational therapists, and nurses. A major advantage of the team approach is that a broad base of knowledge and expertise is available, which can facilitate a team analysis of the etiology of pain and the appropriate treatment approach.
Despite the increasing recognition of the importance of appropriate pain control, as evidenced by the formation of national professional societies such as the American Pain Society and the recently revised accreditation criteria of the Joint Commission on Accreditation of Hospitals mandating pain evaluations of every hospitalized patient, pain is often undertreated. Lack of knowledge on the part of health care professionals regarding the appropriate evaluation and treatment of pain, as well as poor attitudes, particularly the unwarranted fear of addiction on the part of both patient and provider, hamper proper pain control efforts. Appropriate pain control therefore continues to be a significant challenge for the patient, the patients family, and health care providers.
Although the treatment of a patient with chronic pain mandates a comprehensive evaluation of the medical as well as psychological contributors to the etiology, maintenance, and exacerbation of pain, evaluating and treating chronic pain patients with a unimodal, strictly medical approach still occurs. Relying solely on radiographic results of the spine, which have been shown to be unreliable indices of pain, to explain a patient’s pain can lead to failed surgical interventions. Additionally, significant spinal abnormalities are found in patients who are not experiencing back pain. Other detrimental effects of a strictly medical approach to chronic pain include not evaluating chronic pain patients for maladaptive behaviors, such as drug-seeking behaviors or addictive personality traits, which can lead to inappropriate pharmacologic management. Another example of psychological issues that can be overlooked without a comprehensive psychological evaluation are patterns of somatization, which can lead to repeated medical interventions by all-too-willing pain specialists, and further contribute to medical and psychological morbidity. Therefore, the Commission on Accreditation of Rehabilitation Facilities (CARF) only accredits chronic pain programs that are interdisciplinary in both their evaluation and treatment of patients and require as part of the core pain team a psychologist or psychiatrist.
Psychological Assessment of the Chronic Pain Patient
The objectives of the psychological evaluation of the patient with chronic pain are as follows: (1) To determine the degree of psychological adaptation to chronic pain, including mood state, coping skills, effect on family, and level of physical functioning. (2) To evaluate the patient’s psychological state before his or her pain began, which would include personality factors that may influence pain etiology. (3) To determine the role of psychological factors in terms of the etiology, maintenance, and exacerbation of pain. (4) To identify environmental reinforcers of chronic pain and illness behaviors such as family, litigation status, and disability insurance status. (5) To evaluate the likelihood of the development of a chronic pain-related disability. (6) To predict outcome of invasive procedures such as surgical implantation of spinal cord stimulators or continuous infusion pumps.
The standard pain center evaluation protocol utilizes a pain questionnaire, a structured clinical interview, pain assessment measures (including pain intensity rating scales and the McGill Pain Questionnaire), and a psychological evaluation of the patient.
The pain questionnaire should be designed to yield objective clinical outcome measures, and include information such as demographic characteristics, pain descriptors such as throbbing or gnawing, what makes the pain better and worse, whether there is interference with sleep, and circumstances related to the onset of pain. Also included typically are a review of prior nonpharmacologic interventions and their efficacy, specific current and past medication use to treat symptoms, litigation and compensation status, job status, job satisfaction, and specific occasions when pain interferes with quality of life.
The clinical interview should review the patient’s pain complaints, onset of pain and relationship to trauma, prior medical and psychiatric history, prior alcohol and drug usage, current marital and family environment, current functional level, utilization of coping skills, disability status, motivational level to return to work, the possibility of secondary gain issues, ability to experience restful sleep at night, and beliefs and cognitions about his or her pain.
Measures of psychological status typically include a measure of mood state such as the Beck Depression Inventory (BDI). The BDI, a 20-item test using a 0-3 rating scale for each item, is one of the most widely used tests with chronic pain patients because it is a relatively quick measure of depression, a mood state closely linked with chronic pain. The Minnesota Multiphasic Personality Inventory (MMPI, MMPI-2), one of the most widely used and researched tests, is used quite extensively with chronic pain patients. The MMPI is a 566-question true-false test that evaluates the presence of psychopathology through three validity scales (the degree to which respondents may be trying to distort their true persona), and 10 clinical scales: Hypochondriasis, Depression, Hysteria, Psychopathic Deviance (history of antisocial behavior and nonconformance), Paranoia, Psychasthenia (obsessive—compulsive tendencies and other expressions of anxiety), Schizophrenia, Hypomania, Masculinity-Femininity, and Social Introversion. Other measures include the Symptom Checklist 90-Revised (SCL-90R), a commonly used assessment of psychological symptom patterns, which evaluates nine symptom dimensions: somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, and psychoticism.
The Coping Strategies Questionnaire, a 48-item questionnaire using a 7-point Likert-type scale, assesses six cognitive coping responses and two behavioral responses to pain: catastrophizing, ignoring sensations, reinterpreting pain sensations, coping self-statements, diverting attention, praying and hoping, increasing behavioral activity, and increasing pain behaviors. It is an extensively used measure designed to evaluate how pain patients cope with their pain. Coping techniques have been well researched and found to be important mediators of pain perception and functionality. Active coping strategies such as staying busy, ignoring pain, and distraction have been associated with less pain, whereas passive coping strategies such as restricting activities, wishful thinking, and depending on others tend to lead to more pain. Specific coping strategies such as “catastrophizing” correlate strongly in a negative manner with a pain patients prognosis.
As pain management has become more technologically sophisticated and aggressive in its approach, one of the more common uses of the psychological evaluation has been to determine the appropriateness of a potential candidate for an interventional technique. A meta-analysis of the literature on this topic concluded that patients should be excluded from implantable spinal cord stimulators if they have active psychosis, suicidality, untreated major depression, somatization disorder, alcohol or drug dependency, compensation/litigation disincentive to recovery, lack of social supports, or cognitive deficits (severity and type unspecified). Additional considerations for exclusion include unusual pain ratings, significant personality disorders, physical incongruence, a high elevation on the Depression scale of the MMPI, or elevations on four or more MMPI scales.
The clinician needs to take the results from the pain questionnaire, clinical interview, and psychological assessment measures, and with sound clinical judgment formulate a diagnosis and treatment plan that is individually geared to each patient. To paraphrase Sir William Osier, “It is not the type of disease that a patient has that is as important as the type of patient that has the disease.”
Psychological Management of Pain
The psychological intervention with the patient who has chronic pain is an integral part of a multidisciplinary approach to pain management. The overall goal of pain management centers is to return the patient to a more optimal level of functioning. Improved functionality rather than cure of pain is often the focus of pain management. The most commonly utilized psychological approach is the cognitive-behavioral modality. The general objective of cognitive-behavioral treatment strategies is to assist the patient in reconceptualizing his or her belief about pain as an uncontrollable medical symptom to a belief that the patient s response to pain can be under his or her control. The initial step is educating the patient about the mind-body relationship. The effectiveness of this step depends on the patient s defensiveness, level of knowledge about the mechanism of pain, and attitudes about the mind-body relationship. The mainstay of this approach is relaxation training, which helps patients to redirect their focus away from pain, reduce autonomic reactivity, and enhance a sense of self-control. Relaxation training can be accomplished through guided imagery, progressive muscular relaxation, biofeedback, and hypnosis. Relaxation seems to work through reduction of muscle tension, distraction of the patient from his or her pain and body, and a feeling of enhanced control over the body.
Guided imagery has the patient focus on a multisensory imaginary scene. Typically, the image is elicited from the patient, and the psychotherapist guides the patient through the image, substituting sensations such as warmth or numbness for pain. Diaphragmatic breathing is an important part of the relaxation experience, distracting the patient even further.
In progressive muscular relaxation, patients are taught to alternately tense and relax individual muscle groups throughout the body. Only nonpainful muscle groups and body locations are used. Patients learn to recognize and differentiate feelings of tension and relaxation.
Biofeedback is a particularly effective modality for teaching chronic pain patients relaxation as well as self-regulation of physiological processes. Biofeedback monitors ongoing physiological processes such as muscle tension, heart rate, temperature, and even brain waves (called electroencephalographic neurofeedback) and provides the patient with visual and auditory feedback. Body sensors attached to a computer enables the patient to achieve relaxation, which can increase pain tolerance, decrease emotional distress, and even relax specific muscle spasms. Physiological self-control leads to a sense of control, better coping skills, and hopefulness. Pain syndromes with which biofeedback is most effective include headaches, transmandibular joint dysfunction, myofascial pain syndrome, fibromyalgia, and pain exacerbated by stress or anxiety.
Hypnosis is another particularly effective therapeutic technique with pain patients. It not only teaches patients relaxation, but also enables them to experience an analgesic reinterpretation of their pain, experiencing numbness, for example, instead of pain. In one study, women with metastatic breast carcinoma pain undergoing weekly group therapy with self-hypnosis had significantly lower pain ratings over 1 year than a control group.
In addition to education and relaxation training, an essential part of the cognitive-behavioral approach is cognitive restructuring. With this technique, patients are taught to identify maladaptive negative thoughts that pervade their thinking and to replace them with more constructive and adaptive positive thoughts. The maladaptive thoughts often take the form of statements about oneself or ones illness that are negative, and can include overgeneralizing or catastrophizing. Maladaptive thoughts patients with chronic pain typically have include “Pain signifies something is terribly wrong,” “Pain means I need more surgery,” and “No one can help me, it’s hopeless.”
A National Institutes of Health technology assessment conference on the efficacy of mind-body approaches for the treatment of chronic pain and insomnia found “strong” to “moderate” evidence to support the use of relaxation techniques, hypnosis, cognitive-behavioral therapy, and biofeedback in reducing chronic pain. The American Psychological Association has specified that the psychological treatment of chronic pain is one of 25 areas for which there is empirical validation for psychological intervention.
Psychotherapy also plays an essential role in the psychological intervention with pain patients. This can include supportive psychotherapy, group therapy, psychoanalytic (dynamic) psychotherapy, and/or family therapeutic interventions.
Nevertheless, there are barriers to the integration of these psychological therapies into chronic pain management practice. These barriers include a continued overemphasis on the biomedical model, a lack of standardization of psychological techniques, physician reluctance to refer to psychologists (due to lack of awareness of benefits, and concern regarding patient feeling that the physician perceives their pain as imaginary or “in their head”), and poor insurance reimbursement.
In conclusion, the psychological evaluation of patients suffering with chronic pain is based on a comprehensive evaluation of them and their pain. The evaluation protocol typically uses a pain questionnaire, a structured clinical interview, pain assessment measures, and psychological testing of the patient. The psychological treatment of the patient with pain is most often a cognitive-behavioral approach, with relaxation training as the mainstay. The assessment and management of the patient with chronic pain underscore the important role of mental health care providers in their care.
References:
- Beck, A. T., Rush, A. J., Shaw, B. E, & Emery, G. (1979). Cognitive therapy of depression. New York: Guilford.
- Block, A. R., Kremer, E. E, & Fernandez, E. (Eds.). (1999). Handbook of pain syndromes—Biopsychosocial perspectives. Mahwah, NJ: Erlbaum.
- Bradley, L. A. (1996). Cognitive-behavioral therapy for chronic pain. In R. Gatchel & D. Turk (Eds.), Psychological approaches to pain management {pp. 00-00). New York: Guilford.
- Butcher, N. B., Dahlstrom, W. G., Graham, J. R., et al. (1989). MMPI-2, manual for administration and scoring. Minneapolis: University of Minnesota Press.
- Derogatis, L. R. (1977). The SCL—90R: Administration scoring and procedures manual I. Baltimore: Clinical Psychometrics Research.
- Flor, H., & Birbaumer, N. (1993). Comparison of the efficacy of EMG biofeedback, cognitive-behavior therapy, and conservative medical interventions on the treatment of chronic musculoskeletal pain. Journal of Consulting and Clinical Psychology, 61, 653—658.
- Fordyce, W. E. (1976). Behavioral methods in chronic pain and illness. St. Louis, MO: Mosby.
- Gatchel, R., & Turk, D. C. (Eds.) (1996). Psychological approaches to pain management—A practitioners handbook. New York: Guilford.
- Holzman, A. D., & Turk, D. C. (Eds.). (1986). Pain management—A handbook of psychological treatment approaches. New York: Pergamon.
- Keller, L. S., & Butcher, J. N. (Eds.). (1991). Assessment of chronic pain patients with the MMPI-2. Minneapolis: University of Minnesota Press.
- Lefkowitz, M., Lebovits, A. H., Wlody, D., & Rubin, S. (Eds.). A practical approach to pain management. Boston: Little Brown.
- Melzack, R. (1975). The McGill Pain Questionnaire: Major properties and scoring methods. Pain, 1, 277-299.
- Nelson, D. V., Kennington, M., & Novy, D. M. (1996). Psychological selection criteria for implantable spinal cord stimulators. Pain Forum, 5, 93-103.
- Romano, J. M., & Turner, J. A. (1985). Chronic pain and depression: Does the evidence support a relationship? Psychological Bulletin, 97, 18-34.
- Rosenstiel, A. K., & Keefe, F. J. (1983). The use of coping strategies in chronic low back pain patients: Relationship to patient characteristics and current adjustment. Pain, 17, 33-44.
- Spiegel, D., & Bloom, J. (1983). Group therapy and hypnosis reduce metastatic breast carcinoma pain. Psychosomatic Medicine, 45, 333-339.
- Turk, D. C., & Melzack, R. (2001). Handbook of pain assessment (2nd ed.). New York: Guilford.
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