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MEDICAL BIOLOGY: ON OBSESSIVE-COMPULSIVE DISORDER

The following points are made by Michael A. Jenike (New Engl. J. Med. 2004 350:259):

1) Consider the following case: A 33-year-old woman has a seven-year history of hand washing for two to six hours a day, as well as urges to check doors and stoves extensively before leaving her home. Her life is restricted, and her family members are upset about her behavior.

2) The above description is that of a typical patient with an anxiety disorder called "obsessive-compulsive disorder" (OCD), which affects 2 to 3 percent of the world's population.(1) The patient has a general sense that something terrible may occur if a particular ritual is not performed, and the failure to perform a ritual may lead immediately to severe anxiety or a very uncomfortable, nagging feeling of incompleteness. In addition to checking and washing rituals, patients with OCD often present with persistent intrusive thoughts, extreme slowness or thoroughness, or doubts that lead to reassurance-seeking rituals. Patients with OCD commonly seek care from physicians other than psychiatrists. For example, in one study, 20 percent of patients who visited a dermatology clinic had OCD, which had been previously diagnosed in only 3 percent.(2)

3) The mean age at the onset of OCD ranges from 22 to 36 years, with the disorder developing in only 15 percent of patients older than 35 years.(3) Men tend to have an earlier age at onset than women, but women eventually catch up, and roughly 50 percent of adults with OCD are women.(3) OCD is typically a chronic disorder with a waxing and waning course.(3) With effective treatment, the severity of symptoms can be reduced, but typically some symptoms remain.(3) On average, people with OCD see three to four doctors and spend more than nine years seeking treatment before they receive a correct diagnosis. It takes an average of 17 years from the onset of OCD to obtain appropriate treatment.

4) OCD tends to be underdiagnosed and undertreated. Patients may be secretive or lack insight about their illness. Many health care providers are not familiar with the symptoms or are not trained in providing treatment. Some people may not have access to treatment, and sometimes insurance plans do not cover behavioral therapy, although the situation is improving. This lack of access or coverage is unfortunate, since earlier diagnosis and proper treatment can help patients to avoid the suffering associated with OCD and lessen the risks of related problems, such as depression, marital difficulties, and problems related to employment.(4)

5) OCD may have a genetic basis.(5) Concordance for OCD is greater among pairs of monozygotic twins (80 to 87 percent) than among pairs of dizygotic twins (47 to 50 percent). The prevalence of OCD is increased among the first-degree relatives of patients with OCD, as compared with the relatives of control subjects, and the age at onset in the proband (the patient, the index case) is inversely related to the risk of OCD among the relatives.(5) There is evidence of a dominant or codominant mode of transmission of OCD.

6) In rare cases, a brain insult such as encephalitis, a streptococcal infection (in children), striatal lesions (congenital or acquired), or head injury directly precedes the development of OCD. There is some evidence of a neurologic basis for OCD. For example, patients with OCD have significantly more gray matter and less white matter than normal controls, suggesting a possible developmental abnormality. Neuroimaging studies have documented consistent differences in regional brain activity between patients with OCD and control subjects, and the abnormal activity in patients with OCD shifts toward normal after either successful treatment with serotonin-reuptake inhibitors or effective behavioral therapy.

References (abridged):

1. Diagnostic and statistical manual of mental disorders, 4th ed.: DSM-IV. Washington, D.C.: American Psychiatric Association, 1994

2. Fineberg NA, O'Doherty C, Rajagopal S, Reddy K, Banks A, Gale TM. How common is obsessive-compulsive disorder in a dermatology outpatient clinic? J Clin Psychiatry 2003;64:152-155

3. Maj M, Sartorius N, Okasha A, Zohar J, eds. Obsessive-compulsive disorder. 2nd ed. Chichester, England: John Wiley, 2002

4. The Expert Consensus Panel for Obsessive-Compulsive Disorder. Treatment of obsessive-compulsive disorder. J Clin Psychiatry 1997;58:Suppl 4:2-72

5. Pauls DL, Alsobrook JP II, Goodman W, Rasmussen S, Leckman JF. A family study of obsessive-compulsive disorder. Am J Psychiatry 1995;152:76-84

New Engl. J. Med. http://www.nejm.org

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