Illness perceptions: a new paradigm for psychosomatics?

Typically, psychosomatic medicine has seen disease as an endpoint and has focused on the role of psychological factors in etiology or on the psychopathological consequences of illness. In contrast, the illness perception approach begins with the patient's experience of their illness and the main emphasis is on the patient's own model of their condition. Just as people construct representations of the external world to explain and predict events, patients develop similar cognitive models of the bodily changes that reflect either transient symptoms or more long-term illness. We believe that this approach has a widespread application in psychosomatic medicine, because all patients will construct working representations of their illness, and is therefore not limited to those who are regarded as having a pathological response to their condition. The illness perception approach can be best understood in the context of wider changes in psychology. Since the emergence of contemporary cognitive psychology about 40 years ago [1], the focus on cognition and cognitive approaches has dominated all areas of psychological research and theory. For example, social cognition theories have been extremely influential in social psychology [2] and cognitive behavioral methods are now predominant in clinical psychology [3, 4]. Similarly, social cognition models are central to much research in health psychology as a basis for understanding health related behavior [5]. At the core of the cognitive approach is the view that individuals construct models, internal representations, or schema, which reflect their pooled understanding of previous experiences and are used for interpreting new ones and planning their behavior. Early work on the perception of physical symptoms identified personal schema, selective attention, and the role of interpretive processes as important in making sense of both normal physiological changes [6] and the symptoms of illnesses such as diabetes [7]. Studies by Leventhal showed that patients' emotional response to changes in tumor size following chemotherapy for lymphoma were a function of their own personal cognitive model of the illness. From this and other studies Leventhal developed a self-regulatory model whereby patients construct their own representations or models which help them make sense of their experience and provide a basis for their own coping responses [8]. This representation contains core components, beliefs about the etiology of the illness, its symptoms and label, the personal consequences of the illness, how long it will last, and the extent to which the illness is amenable to control or cure. These components show logical interrelationships. For example, a strong belief that the illness can be cured or controlled is typically associated with a short perceived illness duration and relatively minor consequences. Patient models of their illness are, by their nature, private. In medical consultations patients are often reluctant to discuss their beliefs about their illness because they fear conflict with their doctor or risk being thought of as stupid or misinformed. Until recently, the assessment of illness perceptions has been by open-ended interviews designed to encourage patients to elaborate their own ideas about their illness. We have developed a new scale called the Illness Perception Questionnaire that can be used in a variety of physical illnesses and should make assessment more efficient for researchers [9]. Other recent developments have included scales for specific illnesses such as diabetes [10] and a scale to assess specific beliefs about medication [11]. In our work we have found patient models to vary widely across a number of chronic illnesses, even among individuals with the same disease severity [9]. For one person, diabetes may be seen as a relatively minor, time-limited condition caused by a diet high in sugar, whereas another with equivalent disease may see it as a genetic condition lasting for the rest of their life and with catastrophic consequences. From a clinician's perspective it may be very difficult to detect these differences in routine consultations, but they will become apparent in later responses to illness and compliance with treatment. Whereas most current research has focused