Although the specific symptoms may vary over time, hypochondriacal concerns last for at least 6 months despite appropriate medical evaluation and assurance. Elderly patients with hypochondriasis may also have one or more medical disorders, but these do not explain the nature or the severity of the reported symptoms. Despite significant similarities among the somatoform disorders, differentiation is usually straightforward. Somatization disorder and undifferentiated somatoform disorder differ in the number and types of symptoms and severity. Somatization disorder is characterized by multiple symptoms, whereas somatic pain disorder is focused on pain, usually in one location.
Hypochondriasis is distinguished by preoccupation with the underlying cause of the symptoms.
The somatoform disorders must be distinguished from a conscious or intentional attempt to appear physically ill, such as occurs in factitious disorder or malingering. In factitious disorder, which is extremely rare in the elderly, the conscious motivation is to assume the sick role and therefore obtain medical evaluation and treatment. In malingering, which is more common, external gain is experienced by rewards associated with remaining ill, such as financial compensation or avoidance of duty. Medical disorders are ruled out on the basis of the history, physical examination, and laboratory testing. Although extensive testing should be avoided, the physician must remember that the patient presenting with a somatoform disorder also may develop a serious medical disorder.