Obsessive Compulsive Disorder - Types Of Anxiety Disorders: Mental Health

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Obsessive-compulsive disorder

The experience: A graduate student, age 26, has thoughts every day that he can't get out of his head. He worries that he'll get sick from germs on his computer keyboard. He washes his hands repeatedly and keeps rearranging objects on his desk and in the bathroom in an attempt to relieve the anxiety he feels about contamination. He has experienced tension with his fiancée because of this problem. He realizes that his fears are farfetched and that he spends too much time washing his hands and rearranging things, but if he tries to stop, he becomes tense and anxious. At his fiancée's insistence, he sees a psychiatrist, who diagnoses obsessive-compulsive disorder (OCD).

Symptoms: OCD is characterized by obsessions (distressing thoughts, worries, or urges that are involuntary and occur repeatedly) and compulsions (ritualized behaviors that the individual uses in an attempt to feel safe). The most common obsessions involve persistent thoughts of becoming contaminated, having neglected to do something (such as turn off the oven), having done something terrible (such as harm someone), or needing to have objects in a particular order. Aggressive impulses and pornographic thoughts are also common. Compulsions can include handwashing, repeatedly checking something (for example, that the door is locked or that the stove is off), or mental acts such as praying, counting, or repeating words.

Obsessive thoughts or compulsive behaviors do not necessarily mean you have OCD. Such thoughts are normal when you are under stress or worried about changes in your life. Many people are obsessed with forgetting something, which drives them to compulsively make lists of things to buy or do. Obsessive organization can be useful to lawyers, doctors, and others with demanding occupations. Many sports fans are obsessed with the standings of their favorite teams and feel compelled to check the newspaper or Internet frequently for the latest scores. What sets these symptoms apart from OCD is their frequency and the level of distress they cause.

People with OCD have obsessions, compulsions, or both for more than an hour a day. These thoughts or actions often cause significant distress and can interfere with the individual's ability to function at work, in relationships, or in any normal routine. Unlike children, many adults with OCD eventually realize that their obsessions or compulsions are unreasonable. But their attempts to eliminate the compulsive behavior usually fail because doing so causes unbearable anxiety. Obsessions and compulsions can be so distracting that an individual can't concentrate on normal tasks. Although the symptoms are driven by a desire to do something perfectly, their force often derails the person's ability to even complete a task.

Cause: OCD has a strong genetic basis; about 20% of the close relatives of a person with the disorder will also have OCD, and many other family members will have some of the symptoms. Brain imaging scans of people with OCD show abnormal nerve cell activity in the basal ganglia, an area of the brain that controls motor function. One theory is that damage to this region during childhood or even before birth increases the risk for OCD. This disorder is also common among individuals with conditions linked to dysfunction in the basal ganglia, such as Tourette's syndrome (a condition marked by repeated sounds and movements). However, experts don't fully understand how abnormalities of the basal ganglia might promote the repetitive thoughts and rituals of OCD.

Low levels of serotonin and high levels of dopamine also seem to play a role in some cases. About 60% of people with this disorder respond to SSRIs, which increase serotonin levels in the brain. Those who don't respond to SSRIs alone tend to improve when given a second agent, such as a tricyclic antidepressant. Finally, some patients improve when given buspirone or another medication that increases serotonin and blocks dopamine. However, it's unlikely that the serotonin and dopamine systems are solely responsible for OCD because many patients don't respond favorably to any of the drugs that affect these neurotransmitters. In fact, some become worse.

OCD may be related to a common type of infectious disease — the group A beta-hemolytic streptococcal infections, which include strep throat and scarlet fever. Antibodies recruited by the immune system to defeat these bacteria can attack the body's own tissues, damaging the heart and inflaming the joints. There are signs that, especially in children, these antibodies can also infiltrate the brain — the basal ganglia, in particular — causing what is awkwardly named "pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections," or PANDAS. The symptoms of this controversial diagnosis include obsessional thinking and compulsive behavior.

There is additional evidence that these symptoms can appear soon after a streptococcus infection. In a study of children ages 4–13 that compared healthy children with those who had OCD, Tourette's syndrome, and tic disorders, researchers found a high rate of strep infections in the three months before symptoms of these conditions appeared. A child who suffered several infections of the group A beta-hemolytic streptococcal type had nearly 14 times the average risk of developing OCD or related disorders in the following year.

In some people, OCD is a complication of encephalitis or a head trauma. In such cases, the disorder can be temporary or permanent. It's also common among adults with other anxiety disorders, major depression, and eating disorders. In children, it may be linked to learning disorders. In all likelihood, these disorders share many of the same brain abnormalities.

Prevalence: About 1% of the population has OCD, and the lifetime rate is about 2.5%. It affects an estimated 1 in 50 adults and 1 in 200 children.

Who's at risk: Some studies show that OCD affects equal numbers of men and women; other studies indicate a slight predominance among men. It's clear, however, that the disorder is most common among adolescents and young adults, although it sometimes begins in childhood. In males, the disorder usually starts about age 6–15; in females, about age 20–29. People who've had an injury or infection of the brain are at greater risk for OCD.

Effective treatments: SSRIs are a first-line treatment for this condition. While some patients respond better to one SSRI than to another, their symptoms usually don't disappear completely. Often, they're cut by less than half. Therefore, many people need to combine an SSRI with another drug, such as a tricyclic antidepressant or benzodiazepine, or with cognitive behavioral therapy or exposure therapy. The combination of SSRIs and therapy is often more effective than either used alone.

In most cases, OCD is a lifelong disorder. A 40-year follow-up study of patients with OCD admitted to hospitals, published in 2004, found that more than 80% improved but only 20% made a complete recovery. Most of the improvement occurred early in the course of the illness, and about 50% continued to have OCD for more than 30 years, although they often learned to cope with the symptoms.

In very rare cases and as a last resort, neurosurgery can be performed on individuals who don't respond to medications or to behavioral therapy. There are several such procedures, but all aim to sever some of the brain circuitry from the basal ganglia, which is thought to influence repetitive, ritualistic behavior. Only a few medical centers use this procedure, and it's too early to know the long-term outcomes.

Last updated:	September 05, 2008