Mental health in chronic pain
MORE THAN 90 million Americans suffer with chronic pain; it is the most frequent cause of disability in the United States (Okifuji, Turk, & Kalauokalani, 1999). Chronic pain is a complex phenomenon, varying in incidence, prevalence, scope, and nature. Not only does it adversely affect a person’s physical health status, but it also leads to substantial declines in social, emotional, occupational, and economic functioning. Assessing and managing pain has long been a core nursing responsibility. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO)has now issued new guidelines requiring accredited facilities all over the country to develop policies and procedures that formalize this nursing responsibility. The commitment to the study and treatment of pain is also shown in the recent passage of a law by the U.S. Congress designating the period 2001 to 2011 as “The Decade of Pain Control and Research.”
Although chronic pain is one of the clearest examples of the complex relationship between the mind, body, spirit, and environment, many continue to hold beliefs from earlier decades perpetuating the view that pain is either in the body or in the mind. The recognition that psyche and soma do not function as isolated entities has been one of the most important advances in thought about pain. Nowhere is this more evident than with chronic pain sufferers, and working with these patients can be very challenging as their symptoms are complex. Questions related to the multidimensional nature of pain frequently arise and nurses must grapple with these issues. After decades of research, a growing body of evidence supports the importance of certain psychological factors in the chronic pain experience. It is important that nurses understand, not only the organic basis of symptoms, but also the range of psychological factors that modulate nociception and influence the pain experience.
Evolution of pain theory
Historically, pain has been dichotomized as either a psychological or a sensory phenomenon. For instance, Aristotle viewed pain as an emotion, and the Stoic philosophers taught that pain could be overcome by “rational repudiation,” e.g., logic and reasoning (Turk & Rudy, 1986). In contrast, the work of vonFrey in 1895 set forth the basic premises of the specificity theory of pain. This theory was highly regarded well into the 20th century, and viewed pain as a simple sensory event with its own central and peripheral neural mechanism, e.g., a direct-line communication from peripheral pain receptors (nociceptors) through the spinal cord to the pain center in the brain (Muller, 1942).
In 1965, with the introduction of the gate control theory of pain (Melzack & Wall, 1965), a paradigm shift occurred influencing the way pain was viewed and studied. This theory synthesized features of prevailing research and clinical phenomena, and attempted to explain the neural mechanisms underlying the transmission of nociceptive information. A major contribution of this theory is that pain became acknowledged as a complex, multidimensional experience entailing not just aversive sensory and affective experiences, but also behavioral changes and adjustment in motivation, mood, and cognition. The importance of psychological factors in mediating the pain experience, in exacerbating pain problems, and influencing pain behavior were identified as important components of the total pain experience.
Another model to have a major impact in chronic pain research and treatment is the operant conditioning model (Fordyce, 1976). Because pain is not directly observable, all that can be known about pain is grounded in behavioral manifestations, either, verbal or nonverbal, from the pain sufferer. Pain behaviors elicit responses from others, e.g., attention, permission to avoid undesirable activities; these responses reinforce and increase the likelihood of such behaviors being displayed, even in the absence of nociceptive information. According to this model, pain behaviors, rather than “pain per se,” are the targets of treatment interventions. The operant approach radically departs from the traditional sensory view of pain; nociception is viewed as neither a necessary or sufficient condition. It also departs from the gate control theory by ignoring affective, cognitive, and sensory components of the pain experience, and focuses mainly on motivational aspects.
Today, the most widely accepted framework for understanding pain is the biopsychosocial model, which integrates important components of both the gate control theory of pain and the operant conditioning model. Unlike the biomedical perspective, which provides explanations for pain in purely physiological terms, or the psychogenic view, which suggests that pain is a physical manifestation of underlying psychological difficulties, the biopsychosocial model views pain as a reciprocal, dynamic process between biological, psychological, and sociocultural variables. The complex interaction of these variables shapes the persons’ pain experience. Nociception serves as the starting point for a series of events that culminate in the person’s perception of pain and overt pain behaviors. In the process, the pain experience is influenced by physical factors involved in the pain signal transmission, psychological and emotional factors involved in the interpretation of pain signals, and environmental factors that provide incentives or disincentives for recovery (Turk & Okifuji, 2002).
Depression and chronic pain: antecedent or consequence?
Although pain is usually described in terms of its physical characteristics, there is little dispute that it also has an affective component. In fact, the International Association for the Study of Pain (International Association for the Study of Pain, 1979) formalized the coexistence of sensory and affective features of pain into their definition of pain, stating “pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage … Pain is always subjective … If [they] regard their experience as pain and if [they] report it in the ways as pain caused by tissue damage, it should be accepted as pain” (p. 250). In a framework conceptualizing these dual defining features of pain, Fernandez, Clark, & Rudick-Davis (Fernandez, Clark, & Rudick-Davis, 1999) describe the boundaries between pain sensation and affect as being fluid and having “reciprocal determinism.” This implies that pain sensation and affect influence each other reciprocally, but not necessarily in a proportional way. Pain sensation and affect also function as a system, change in one has the capacity to change the other, as well as changing the whole.
Tags: Chronic pain