Information on the following diseases can be found in the Related Disorders section of this report:

• Obsessive-Compulsive personality disorder
• Anorexia nervosa
• Bulimia
• Schizophrenia
• Manic Depression (Bipolar Disorder)
• Tourette syndrome
• .

Obsessive compulsive disorder is characterized by recurrent obsessive thoughts and compulsive actions. Obsessions are persistent, repetitive ideas, thoughts, impulses, or images that the affected individual knows are senseless. Examples may include thoughts of violence (e.g., repeated impulses to hurt another person), contamination (e.g., persistent concerns regarding the potential for infection from shaking another person's hand), or doubt (e.g., overwhelming concern regarding whether a particular action has been performed, such as whether a door has been locked). Attempts are made to ignore or suppress such thoughts or impulses, or to counteract them with other thoughts or actions. Although the affected individual recognizes that the obsessions are the product of his or her own mind, he or she still finds them difficult to resist.

Compulsions are repetitive, purposeful, and intentional behaviors that are performed in response to an obsessive thought, according to certain rules, or in a stereotyped fashion. The behavior is designed to neutralize obsessive thoughts and/or to avoid some dreaded, anticipated event or situation. However, either the activity is not connected in a realistic way with what it is designed to neutralize or prevent, or it is clearly excessive. Compulsions are usually accompanied by a desire to resist the compulsion (at least initially). Although adults affected with this disorder recognize that their behavior is excessive or unreasonable, affected children may not recognize this fact. Affected individuals do not derive pleasure from carrying out the activity, although doing so provides a release of tension. The most common compulsive actions include excessive hand-washing and repeated counting, checking, and/or touching.

When an individual with obsessive compulsive disorder attempts to resist a compulsion, he or she experiences a sense of mounting tension that can be immediately relieved by yielding to the compulsion. In the course of the illness, after repeated failure at resisting compulsions, the person may yield to them and no longer experience a desire to resist such impulses.

Depression and anxiety are commonly associated with this disorder. Many affected individuals attempt to avoid situations that tend to trigger obsessive thought patterns. For example, a person with obsessions concerning unsanitary conditions may avoid using public restrooms and shaking hands with strangers, and he or she may take several showers each day.

Obsessive compulsive disorder may occur in a mild, moderate, or severe form. In rare cases, actions dictated by obsessive thoughts may monopolize an affected individual's daily routine, significantly interfering with necessary daily functions (school, work, social interactions, etc.). Obsessive compulsive disorder is usually chronic, with waxing and waning of symptoms.

The exact cause of obsessive compulsive disorder is not known. In March 2006, scientists at the National Institutes of Health's (NIH) National Institute on Alcohol Abuse and Alcoholism (NIAAA) reported that they have identified a previously unknown gene variant that doubles an individual's risk for obsessive-compulsive disorder. The new variant (allele) is a component of the serotonin transporter gene (SERT), site of action for the selective serotonin reuptake inhibitors (SSRIs) that are today's mainstay medications for OCD, other anxiety disorders and depression.

Several researchers have thought that the disorder may have a genetic component because it tends to occur in more than one member of a family. Studies have indicated that patients with this disorder have abnormally fast metabolism in certain areas of the brain. The findings point to the basal ganglia including their component, the caudate nuclei.

Some researchers at the National Institutes of Health have suggested that Group A beta hemolytic Streptococcus (a bacteria that causes strep throat and rheumatic fever) may provide an environmental trigger in genetically susceptible obsessive compulsive disorder families. They suspect that an immunological reaction set off by the bacteria may contribute to the onset of obsessive compulsive disorder. These findings are very preliminary and more studies are needed to determine the exact nature of this possible relationship.

OCD usually begins during adolescence or early adulthood. It affects males and females in equal numbers. The mild form of this disorder is relatively common; it is estimated that as many as five million Americans may have this disorder, but only a very small percentage of them are impaired significantly enough to warrant treatment.

Symptoms of the following disorders may resemble those of obsessive compulsive disorder. Comparisons may be useful for a differential diagnosis:

Obsessive-compulsive personality disorder (OCPD) is a psychiatric condition that is often confused with obsessive compulsive disorder. OCPD, which typically becomes apparent in early adulthood, is not characterized by obsessions and compulsions, as is the case with obsessive compulsive disorder. Rather, affected individuals exhibit a rigid, inflexible need for control, orderliness, and perfection in every situation, ultimately interfering with task completion, leisure activities, and friendships. For example, individuals with obsessive-compulsive personality disorder tend to demonstrate exacting attention to procedures, rules, and lists, exhibit excessive care over unnecessary details, and repeatedly check the same areas for mistakes, to the point where they neglect the intended purpose of the task. Leisure activities are approached with the same standards--i.e., as serious tasks requiring control, rigid organization, and perfection. A failure to achieve perceived perfection and control over personal activities, work assignments, or financial situations may result in extreme uncertainty, anxiety, and/or anger.

Anorexia nervosa is an illness of self-starvation resulting in marked weight loss. It is characterized by a disturbed sense of body image and anxiety about weight gain. Women with this disorder may also experience absence of menstrual periods. The self-starvation is not a true compulsion because the person may wish to resist it only because of its harmful consequences. (For more information on this disorder, choose "Anorexia Nervosa" as your search term in the Rare Disease Database.)

Bulimia is a psychiatric disorder consisting of binge eating, often followed by self-induced vomiting or purges with the use of laxatives and diuretics. The majority of patients are female. Persons with this disorder commonly fear they will be unable to stop eating voluntarily. In a calm, concerned, stable environment, and with supportive psychotherapy, patients can acquire a better self-image and develop more stable eating patterns. (For more information on this disorder, choose "Bulimia" as your search term in the Rare Disease Database.)

Some excessive activities such as aberrant sexual behavior, pathological gambling, and alcohol and drug dependence or abuse may be referred to as "compulsive." However, the activities are not true compulsions because the person derives pleasure from the particular activity and may wish to resist it only because of harmful secondary consequences.

In schizophrenia, compulsive behavior is common, but it is usually due to delusions rather than to true compulsions. A person with a true delusion usually has a fixed conviction that cannot be shaken, while a person with an obsession usually recognizes the senselessness of the urge. However, in some cases of obsessive compulsive disorder, there may be bizarre delusions and other symptoms unrelated to the disorder that justify the additional diagnosis of schizophrenia.

Bipolar manic depression is a mental illness marked by intense mood swings with possible remissions and recurrences. Depression may be most common and may last at least a full day and perhaps several weeks or longer. Manic symptoms involve hyperactivity and feelings of invincibility, happiness, and restlessness. During a major depressive episode, obsessive brooding about potentially unpleasant circumstances or about possible alternative actions is common. However, these symptoms are usually not experienced as senseless but as meaningful, although possibly excessive. Therefore, these are not true obsessions. (For more information on this disorder, choose "Bipolar Manic Depression" as your search term in the Rare Disease Database.)

Obsessive compulsive disorder may be associated with the following disorder as a secondary characteristic. It is not necessary for a differential diagnosis:

Tourette syndrome is a neurological movement disorder that tends to begin in childhood between the ages of two and 16. The disorder may be characterized by involuntary muscular movements (tics) and uncontrollable vocal sounds. In some cases, affected individuals may exhibit compulsive behavior and/or vocalize inappropriate words. Tourette syndrome and obsessive compulsive disorder tend to occur in more than one member of the same family. Females in Tourette families tend to exhibit obsessive compulsive disorder while males tend to display more severe Tourette syndrome. (For more information on this disorder, choose "Tourette" as your search term in the Rare Disease Database.)

OCD is considered an anxiety disorder. The two types of treatment available for anxiety disorders are medication and psychotherapy.

Psychiatrists or other physicians can prescribe medications for anxiety disorders. These physicians often work closely with psychologists, social workers, or counselors who provide psychotherapy.

Some of the newest antidepressants are the selective serotonin reuptake inhibitors (SSRIs). They tend to have fewer side effects than older antidepressants. SSRIs prescribed for OCD include fluoxetine, sertraline, fluvoxamine, paroxetine, and citalopram. SSRIs may be used to treat people who have a panic disorder in combination with OCD. In addition, the antidepressant clomapramine may be prescribed for OCD.

The Obsessive-Compulsive Foundation has published articles on OCD medications for adults and children. To contact the foundation, see the Resources section of this report.

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government website.

For information about clinical trials being conducted at the National Institutes of Health (NIH) in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:
www.centerwatch.com

As of Spring 2006, more than 35 trials were listed for OCD on the ClinicalTrials.gov web site. Additional listings of clinical trials may be found at www.centerwatch.com.

In March 2006, researchers from the National Institute on Alcohol Abuse and Alcoholism reported work in which they identified a previously unknown gene variant that doubles an individual's risk for OCD. It is thought that the gene variant creates too many serotonin transporters, causing disabling characteristics in individuals affected by OCD. Serotonin transporters are proteins that facilitate the communication of chemical messages between cells.

Listings on the www.clinicaltrials.gov web site include a Phase IV study of the drug Escitalopram for the treatment of obsessive compulsive disorder. This study is sponsored by Massachusetts General Hospital. Contact Mariko Jameson at (617) 726-9281 or mjameson@partners.org for information.

A study of transcranial magnetic stimulation (TMS) in treating obsessive compulsive disorder is being sponsored by the New York State Psychiatric Institute. For information, contact Antonio Mantovani, MD, at (212) 543-6081 or amantovani@hotmail.com.

For information on a study of deep brain stimulation and OCD, sponsored by the National Institute of Mental Health, contact the NIH Patient Recruitment Office listed above.

TEXTBOOKS
Beers MH, Berkow R., eds. The Merck Manual, 17th ed. Whitehouse Station, NJ: Merck Research Laboratories; 1999:1517.

Berkow R., ed. The Merck Manual-Home Edition.2nd ed. Whitehouse Station, NJ: Merck Research Laboratories; 2003:611-12.

Frances A., chmn. bd. eds. Diagnostic and Statistical Manual of Mental Disorders: DSM IV. 4th ed. American Psychiatic Association. Washington, DC; 1994:417-23.

Gabbard GO, ed. Treatment of Psychiatric Disorders. 2nd ed. American Pychiatric Association. Washington, DC; 1995:1477-98.

Kaplan HI, Sadock BJ, eds. Comprehensive Textbook of Psychiatry/V. 5th ed. William & Wilkins. Baltimore, MD; 1989:984-99.

REVIEW ARTICLES
Cottraux J, Bouvard MA, Milliery M. Combining pharmacotherapy with cognitive-behavioral interventions for obsessive-compulsive disorder. Cogn Behav Ther. 2005;34:185-92.

Abramowitz JS, Taylor S, MCKay D. Potentials and limitations of cognitive treatments for obsessive-compulsive disorder. Cogn Behav Ther. 2005;34:140-47.

Shih RA, Belmonte PL, Zandi PP. A review of the evidence from family, twin and adoption studies for a genetic contribution to adult psychiatric disorders. Int Rev Psychiatry. 2004;16:260-83.

Reinblatt SP, Walkup JT. Psychopharmacologic treatment of pediatric anxiety disorders. Child Adolesc Psychiatr Clin N Am. 2005;14:877-908.

Leonard HL, Ale CM, Freeman JB, et al. Obsessive-compulsive disorder. Child Adolesc Psychiatr Clin N Am. 2005;14:727-43.

FROM THE INTERNET
Obsessive-Compulsive Foundation (OCF)
www.ocfoundation.org