According to the National Institutes of Health, about 2.2 million people in the United States have OCD, although it tends to be underreported, under-recognized, and under-treated. Patients may not be correctly diagnosed for many years. About one-third of adults suffering from OCD report that their symptoms began in childhood.

The cause of OCD is unknown. Some genetic research, however, suggests that there may be an inherited tendency to develop OCD because the development of childhood OCD seems to run in families. Neurobiologic studies suggest that OCD may be caused by abnormally low levels of serotonin. Other research suggests that some maladaptive behaviors are learned from the patient’s environment, and some controversial research suggests OCD may be linked to group A beta-hemolytic streptococcus infection. Some studies suggest the possibility of brain lesions. In addition, major depression, organic brain syndrome, and schizophrenia may occur with OCD. Some researchers find that depression may occur when the individual is no longer able to cope with his symptoms of OCD. Some authorities think that OCD is closely related to some eating disorders. Symptoms usually are noticed between ages 20 and 30, with 75% of patients displaying symptoms before age 30.

The psychiatric history of a patient with OCD may reveal the presence of obsessive thoughts, words, or mental images that persistently and involuntarily invade the consciousness. The patient recognizes that the obsessions are a product of his own mind and they interfere with normal daily activities.

Some common obsessions include:

• thoughts of violence (such as stabbing, shooting, maiming, or hitting)

• thoughts and fears of contamination (images of dirt, germs, or feces)

• repetitive doubts and worries about a tragic event

• repeating or counting images, words, or objects in the environment

• recurrent rituals

• thoughts about maintaining symmetry in his environment.

The patient’s history may also reveal the presence of compulsions—irrational and recurring impulses to repeat a certain behavior. Common compulsions include:

• repetitive touching and arranging of objects, sometimes combined with counting

• doing and undoing (for instance, opening and closing doors or rearranging things)

• excessive washing (especially of hands)

• repetitive checking of the environment (to be sure no tragedy has occurred since the last time he checked)

• constant demanding of reassurance.

In many cases, the patient’s anxiety is so strong that he’ll avoid the situation or the object that evokes the impulse. When the obsessive-compulsive phenomena are mental, observation may reveal no behavioral abnormalities. However, compulsive acts may be observed. Feelings of shame, nervousness, or embarrassment may prompt the patient to hide his behavior and limit these acts to his own private time.

• Impaired functioning in work and school

• Impaired family relationships

• Impaired social functioning

• Depression

• Suicide attempt

• Substance and alcohol abuse in attempt to self-medicate his anxiety and distress

• Physical complications from compulsive behaviors (for example, dermatitis from excessive handwashing)

There are no laboratory tests to diagnose OCD. For characteristic findings in patients with this condition, see Diagnosing obsessive-compulsive disorder, page 108.

Be sure to evaluate the impact of obsessive-compulsive phenomena on the patient’s normal routine. He’ll typically report moderate to
severe impairment of social and occupational functioning.