Seven somatoform disorders are listed in the text revision of the fourth edition of the
Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR): (1) somatization disorder, characterized by many physical complaints affecting many organ systems; (2) conversion disorder, characterized by one or two neurological complaints; (3) hypochondriasis, characterized less by a focus on symptoms than by patients’ beliefs that they have a specific disease; (4) body dysmorphic disorder, characterized by a false belief or exaggerated perception that a body part is defective; (5) pain disorder, characterized by symptoms of pain that are either solely related to, or significantly exacerbated by, psychological factors; (6) undifferentiated somatoform disorder, which includes somatoform disorders not otherwise described that have been present for 6 months or longer; and (7) somatoform disorder not otherwise specified, which is the category for somatoform symptoms that do not meet any of the somatoform disorder diagnoses mentioned previously (
Table 14-1).
The term somatoform derives from the Greek soma for body, and the somatoform disorders are a broad group of illnesses that have bodily signs and symptoms as a major component. These disorders encompass mind-body interactions in which, in ways not well understood, signals within the brain give rise to a patient’s awareness of a serious problem in the body. In addition, minor or as yet undetectable changes in neurochemistry, neurophysiology, and neuroimmunology may result from unknown mental or brain mechanisms that cause illness.
SOMATIZATION DISORDER
Somatization disorder is an illness of multiple somatic complaints in multiple organ systems that occurs over a period of several years and results in significant impairment, treatment seeking, or both. Somatization disorder is the prototypic somatoform disorder and has the best evidence of any of the somatoform disorders for being a stable and reliably measured entity over many years in individuals with the disorder. Somatization disorder differs from other somatoform disorders because of the multiplicity of the complaints and the multiple organ systems (e.g., gastrointestinal and neurological) that are affected. The disorder is chronic and is associated with significant psychological distress, impaired social and occupational functioning, and excessive medical-help-seeking behavior.
Somatization disorder has been recognized since the time of ancient Egypt. An early name for somatization disorder was hysteria, a condition incorrectly thought to affect only women. (The word hysteria is derived from the Greek word for uterus, hystera.) In the 17th century, Thomas Sydenham recognized that psychological factors, which he called “antecedent sorrows,” were involved in the pathogenesis of the symptoms. In 1859, Paul Briquet, a French physician, observed the multiplicity of symptoms and affected organ systems and commented on the usually chronic course of the disorder. Because of these clinical observations, the disorder was called Briquet’s syndrome until the term somatization disorder became the standard in the United States.
Epidemiology
The lifetime prevalence of somatization disorder in the general population is estimated to be 0.2 to 2 percent in women and 0.2 percent in men. Women with somatization disorder outnumber men 5 to 20 times, but the highest estimates may be because of the early tendency not to diagnose somatization disorder in male patients. Nevertheless, it is not an uncommon disorder. With a 5:1 female-to-male ratio, the lifetime prevalence of somatization disorder among women in the general population may be 1 or 2 percent. Among patients in the offices of general practitioners and family practitioners, as many as 5 to 10 percent may meet the diagnostic criteria for somatization disorder. The disorder is inversely related to social position and occurs most often among patients who have little education and low incomes. Somatization disorder is defined as beginning before age 30 years; it usually begins during a person’s teenage years.
Several studies have noted that somatization disorder commonly coexists with other mental disorders. About two thirds of all patients with somatization disorder have identifiable psychiatric symptoms, and up to half have other mental disorders. Commonly associated personality traits or personality disorders are those characterized by avoidant, paranoid, self-defeating, and obsessive-compulsive features. Two disorders that are not seen more commonly in patients with somatization disorder than in the general population are bipolar I disorder and substance abuse.
Etiology
Psychosocial Factors.
The cause of somatization disorder is unknown. Psychosocial formulations of the cause involve interpretations of the symptoms as a social communication whose result is to avoid obligations (e.g., going to a job a person does not like), to express emotions (e.g., anger at a spouse), or to symbolize a feeling or a belief (e.g., a pain in the gut). Strict psychoanalytic interpretations of symptoms rest on the hypothesis that the symptoms substitute for repressed instinctual impulses.
A behavioral perspective on somatization disorder emphasizes that parental teaching, parental example, and ethnic mores may teach some children to somatize more than others. In addition, some patients with somatization disorder come from
unstable homes and have been physically abused. Social, cultural, and ethnic factors may also be involved in the development of symptoms.
Biological Factors.
Some studies point to a neuropsychological basis for somatization disorder. These studies propose that the patients have characteristic attention and cognitive impairments that result in the faulty perception and assessment of somatosensory inputs. The reported impairments include excessive distractibility, inability to habituate to repetitive stimuli, grouping of cognitive constructs on an impressionistic basis, partial and circumstantial associations, and lack of selectivity, as indicated in some studies of evoked potentials. A limited number of brain-imaging studies have reported decreased metabolism in the frontal lobes and the nondominant hemisphere.
GENETICS.
Genetic data indicate that in at least some families, the transmission of somatization disorder has genetic components. Somatization disorder tends to run in families and occurs in 10 to 20 percent of the first-degree female relatives of patients with this disorder. Within these families, first-degree male relatives are susceptible to substance abuse and antisocial personality disorder. One study also reported a concordance rate of 29 percent in monozygotic twins and 10 percent in dizygotic twins, an indication of a genetic effect. The male relatives of women with somatization disorder show an increased risk of antisocial personality disorder and substance-related disorders. Having a biological or adoptive parent with any of these three disorders increases the risk of developing antisocial personality disorder, a substance-related disorder, or somatization disorder.
CYTOKINES.
Cytokines are messenger molecules that the immune system uses to communicate within itself and with the nervous system, including the brain. Examples of cytokines are interleukins, tumor necrosis factor, and interferons. Some preliminary experiments indicate that cytokines contribute to some of the nonspecific symptoms of disease, such as hypersomnia, anorexia, fatigue, and depression. The hypothesis that abnormal regulation of the cytokine system may result in some of the symptoms seen in somatoform disorders is under investigation.
Diagnosis
For the diagnosis of somatization disorder, DSM-IV-TR requires onset of symptoms before age 30 years (
Table 14-2). During the course of the disorder, patients must have complained of at least four pain symptoms, two gastrointestinal symptoms, one sexual symptom, and one pseudoneurological symptom, none of which is completely explained by physical or laboratory examinations.
Clinical Features
Patients with somatization disorder have many somatic complaints and long, complicated medical histories. Nausea and vomiting (other than during pregnancy), difficulty swallowing, pain in the arms and legs, shortness of breath unrelated to exertion, amnesia, and complications of pregnancy and menstruation are among the most common symptoms. Patients frequently believe that they have been sickly most of their lives. Pseudoneurological symptoms suggest, but are not pathognomonic of, a neurological disorder. According to DSM-IV-TR, they include impaired coordination or balance, paralysis or localized weakness, difficulty swallowing or lump in throat, aphonia, urinary retention, hallucinations, loss of touch or pain sensation, double vision, blindness, deafness, seizures, or loss of consciousness other than fainting.
Psychological distress and interpersonal problems are prominent; anxiety and depression are the most prevalent psychiatric conditions. Suicide threats are common, but actual suicide is rare. If suicide does occur, it is often associated with substance abuse. Patients’ medical histories are often circumstantial, vague, imprecise, inconsistent, and disorganized. Patients classically (but not always) describe their complaints in a dramatic, emotional, and exaggerated fashion, with vivid and colorful language; they may confuse temporal sequences and cannot clearly distinguish current from past symptoms. Female patients with somatization disorder may dress in an exhibitionistic manner. Patients may be perceived as dependent, self-centered, hungry for admiration or praise, and manipulative.
Somatization disorder is commonly associated with other mental disorders, including major depressive disorder, personality disorders, substance-related disorders, generalized anxiety disorder, and phobias. The combination of these disorders and the chronic symptoms results in an increased incidence of marital, occupational, and social problems.
Differential Diagnosis
The three features that most suggest a diagnosis of somatization disorder instead of another medical disorder are (1) the involvement of multiple organ systems, (2) early onset and chronic course without development of physical signs or structural abnormalities, and (3) absence of laboratory abnormalities that are characteristic of the suggested medical condition. In the process of diagnosis, the astute clinician considers other medical disorders that are characterized by vague, multiple, and confusing somatic symptoms, such as thyroid disease, hyperparathyroidism, intermittent porphyria, multiple sclerosis, and systemic lupus erythematosus.
Mood and anxiety disorders often, but not always, have prominent somatic symptoms, which do not exist separately from the mood or anxiety disorder. Somatization disorder may be diagnosed, however, as a comorbid condition with mood and anxiety disorders. Schizophrenia and other psychotic disorders with multiple somatic delusions need to be differentiated from the nondelusional somatic complaints of individuals with somatization disorder. Hallucinations can occur as pseudoneurological symptoms and must be distinguished from the typical hallucinations seen in schizophrenia. Somatization disorder symptoms are usually easier to distinguish from psychotic disorders than is the case for hypochondriasis, the disease fears of which can reach delusional quality.
Course and Prognosis
Somatization disorder is a chronic, undulating, and relapsing disorder that rarely remits completely. It is unusual for the individual with somatization disorder to be free of symptoms for greater than 1 year. Research has indicated that a person diagnosed with somatization disorder has approximately an 80 percent chance of being diagnosed with this disorder 5 years later. Although patients with this disorder consider themselves to be medically ill, good evidence is that they are no more likely to develop another medical illness in the next 20 years than are people without somatization disorder.
Treatment
Somatization disorder is best treated when the patient has a single identified physician as primary caretaker. When more than one clinician is involved, patients have increased opportunities to express somatic complaints. Primary physicians should see patients during regularly scheduled visits, usually at monthly intervals. The visits should be relatively brief, although a partial physical examination should be conducted to respond to each new somatic complaint. Additional laboratory and diagnostic procedures should generally be avoided. Once somatization disorder has been diagnosed, the treating physician should listen to the somatic complaints as emotional expressions rather than as medical complaints. Nevertheless, patients with somatization disorder can also have bona fide physical illnesses; therefore, physicians must always use their judgment about what symptoms to work up and to what extent. A reasonable long-range strategy for a primary care physician who is treating a patient with somatization disorder is to increase the patient’s awareness of the possibility that psychological factors are involved in the symptoms until the patient is willing to see a mental health clinician. In complex cases with many medical presentations, a psychiatrist is better able to judge whether to seek a medical or surgical consultation because of his or her medical training; however, a nonmedical mental health professional can explore the psychological antecedents of the disorder as well, especially if he or she consults closely with a physician.
Psychotherapy, both individual and group, decreases these patients’ personal health care expenditures by 50 percent, largely by decreasing their rates of hospitalization. In psychotherapy settings, patients are helped to cope with their symptoms, to express underlying emotions, and to develop alternative strategies for expressing their feelings.
Giving psychotropic medications whenever somatization disorder coexists with a mood or anxiety disorder is always a risk, but psychopharmacological treatment, as well as psychotherapeutic treatment, of the coexisting disorder is indicated. Medication must be monitored because patients with somatization disorder tend to use drugs erratically and unreliably. Few available data indicate that pharmacological treatment is effective in patients without coexisting mental disorders.
