Psychobiology of Somatoform Disorders
Winfried Rief and Cornelia Exner
SYMPTOMS AND THE HEALTH CARE SYSTEM
Unexplained physical symptoms are one of the major problems of the health care system. Depending on the medical setting under investigation, between 15% and 80% of doctor visits are due to persons with physical symptoms which cannot be accounted for by a clear organic cause. Most common symptoms are pains and aches, gastrointestinal complaints, and cardiovascular symptoms. Kroenke and Mangelsdorff (1989) demonstrated that only about 16% of the most common physical symptoms can be explained by a clear organic pathology. In their longitudinal study, patients with multiple unexplained physical symptoms and with an illness duration of more than four months had the worst prognosis. As will be shown below, unfortunately this is the most frequent combination of features in patients with somatoform disorders. Accordingly, this group of patients is one of the most expensive subgroups in the health care system. Fink (1992) analysed a subgroup of high utilizers of the health care system who had had at least ten inpatient treatments during the last eight years. He found that about 20% of these frequent hospitalizations were due to unexplained physical symptoms.
Some experts believe that illness behaviour is the most typical feature of somatization. Typical features of illness behaviour are frequent doctor visits, wandering around from doctor to doctor and from treatment unit to treatment unit, taking unnecessary medication, urging doctors to do unnecessary investigations which may lead to complications, avoidance behaviour and reduction of social activities, a high number of sick-leaves, and reduced social functioning. Health anxiety is a frequent, but not a necessary condition for the development and maintenance of unexplained physical symptoms. It is unclear whether these features are consequences of the disorder or else maintaining factors, or even the cause of additional physical problems.
Patients with somatoform disorders are also characterized by a specific cognitive-perceptual style. Barsky et al. (1993) emphasized that patients with hypochondriasis and somatoform symptoms have an over-exclusive concept of being healthy. They conceive health as a state of perfect physical well-being without any physical discomfort. However, physical discomfort is a common sensation even to healthy persons. Therefore persons with somatoform disorders are concerned about normal bodily perceptions; they focus their attention on bodily processes, which leads to an amplified perception of physical changes. This can encourage the interpretation of physical discomfort as illness symptoms.
While Barsky's concept of somatosensory amplification (Barsky and Wyshak, 1990) related primarily to patients with hypochondriasis, our own group demonstrated that patients with somatization syndromes without hypochondriasis also tend to catastrophize their perception of physical processes (Rief et al., 1998). Patients with somatization syndromes have a bias to interpret minor physical
Figure XX.1 Somatization from a cognitive–psychobiological perspec-
tive (Rief and Nanke, 1999)
changes (e.g., heart beat acceleration while taking a hot bath) as a possible sign of a severe illness (e.g., cardiomyopathy). This cognitive–perceptual style leads to the behavioural consequences described above. Moreover, the cognitive and behavioural features of somatization interact with biological properties of the disorder and maintain a vicious circle (see Figure XX. 1). Affective consequences such as demoralization, negative affectivity, or depression might present a negative feedback loop that helps to maintain the problem.
AND THEIR CLASSIFICATION
The common feature of the somatoform disorders is the presence of physical symptoms which are not fully explained by a general medical condition, by the direct effect of a substance, or by another mental disorder. The symptoms must cause clinically significant distress or impairment in social functioning. Seeking medical help or para-medical consultation is very frequent. Historically, these syndromes have been labelled 'hysteria', a term which is presendy less used because of stigmatizing effects.
Despite the fact mat single physical complaints are very common, persons with multiple physical complaints represent the most serious subgroup for the health care system. The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994) suggests the diagnosis of somatization disorder for polysymptomatic pictures of somatization. The disorder starts typically before age 30 years, extends over a period of years and is characterized by a