These disorders involve physical symptoms and preoccupation with physical symptoms for which no medical explanation can be found. It is significant (and humbling) to remember, however, that 40% of patients diagnosed with conversion disorder, a somatoform disorder, in one series ended up having an organic cause ultimately found for their symptoms. Somatoform disorders tend to affect women more than men, with the exception of hypochondriasis, which affects men and women equally. Conversion disorder is limited to neurological signs and symptoms, whereas somatization disorder must by definition affect multiple organ systems.
Body Dysmorphic Disorder
Conversion Disorder consists of the apparent loss of one or more neurological functions (such as paralysis of an arm or numbness over half of one's body). Conflict and stress precede the onset of symptoms which do NOT appear to be consciously or intentionally produced. No medical or other explanation exists for the deficit, and it must cause significant social or occupational impairment. Patients with conversion disorder often have la belle indifference, or an inappropriately cavalier attitude toward the deficit. "Oh, yeah, I guess my arm is paralyzed."
Hypochondriasis is preoccupation with the fear of having a serious illness. (Think Woody Allen.)
Body Dysmorphic Disorder involves preoccupation with some imagined defect in one's appearance and is likely related to obsessive-compulsive disorder and the body distortions of anorexia nervosa.
Somatization Disorder must begin before age 30 (the first symptoms usually arise in the teenage years but the illness does not become full blown until the 30s and 40s), and cause significant impairment in social, occupational, or other important areas of functioning. Women are diagnosed with this disorder much more than men. To make this diagnosis, you must have:
4 pain symptoms;
2 gastrointestinal symptoms;
1 sexual symptom;
1 pseudoneurological symptom.
These symptoms cannot be accounted for by a medical condition or by drugs or medications, or if there is a possible medical cause, the symptoms must be grossly in excess of what would be expected from the history and physical examination.
Note that somatization disorder is unconscious; the patients are not deliberately attempting to deceive their providers. They would most likely pass a polygraph examination. This is to be contrasted with two other disorders in which there is a conscious production of symptoms: