The average age of onset for OCD varies among men and women. Men may experience childhood onset, between ages 6 and 15, while women typically experience adult onset, between ages 20 and 30. Two-thirds of all adults with OCD had symptoms before age 15, 80 percent of whom also had symptoms of depression. Given the likelihood of early onset, it is alarming that the average age that a person seeks treatment is 27.
Although OCD usually develops gradually, psychosocial stressors like changes in living situations, relationship problems, or work problems can cause sudden onset. About 70% of people experience a chronic and lifelong course, with worsening and improving symptoms. About 5% have episodic symptoms with partial or complete remission between episodes.
Regardless of a person's age at onset, the content of obsessions does not determine prognosis. The factors associated with a good prognosis include the following:
- Milder symptoms
- Brief duration of symptoms
- Good functioning before full onset
Some people have only obsessions and do not behave compulsively. These people may attempt to suppress their disturbing, intrusive, or inappropriate thoughts by thinking healthy thoughts. This may lead to mental exhaustion, distraction, or concentration problems.