Obsessive-Compulsive Disorder (OCD)

What Is It?

In obsessive-compulsive disorder (OCD), a person is troubled by intrusive, distressing thoughts (obsessions) and feels the pressure to carry out repetitive behaviors (compulsions).

Neuroscientists believe that the brain pathways involved with judgment, planning and body movement are altered in OCD. Environmental influences, such as family relationships or stressful events, can trigger or worsen OCD symptoms.

OCD affects an estimated 2% to 3% of people in the United States. The percentage is about the same in Canada, Korea, New Zealand and parts of Europe. About two-thirds of people with OCD have the first symptoms before they are 25 years old. Only 15% develop their first symptoms after age 35. There is strong evidence that the illness has a genetic (inherited) basis, since about 35% of people with OCD have a close relative who also has the condition. Although 50% to 70% of patients first develop OCD after a stressful life event – such as a pregnancy, a job loss or a death in the family – experts still do not understand exactly how stress triggers the symptoms of this illness.

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