April 27, 2000 -- If you have obsessive-compulsive disorder (OCD), there is a good chance that someone else in your family has it and that your own children are at higher risk for getting it, too.
OCD is a psychiatric disorder in which a person experiences obsessions or recurrent, persistent thoughts or images that are intrusive and inappropriate and cause distress. They are not simply worries about real-life problems.
Troubling thoughts, such as being contaminated after shaking hands, are usually accompanied by compulsions -- repetitive behaviors, like washing hands or checking that your front door is locked -- that a person with OCD feels driven to perform in response to the thoughts. OCD can be a very disabling disorder and is vastly different from many people's common, mild desire to check things, like whether they turned the stove or the iron off before leaving the house.
A study published in the April 2000 issue of the journal Archives of General Psychiatry shows that OCD occurs much more commonly among relatives of OCD sufferers than relatives of people without OCD. The researchers concluded that they have enough evidence to suggest that OCD is a familial disorder.
The study's authors write in the study that the role of heredity in OCD, which has long been suspected by clinicians, has been supported by several studies that included twins, but results from other family studies have been inconsistent.
Lead author Gerald Nestadt, MD, MPH, says that in addition to finding that OCD runs in families, the study showed "the earlier individuals develop these symptoms, the more likely they are to have a familial type of this condition. That is, there is more reason to suspect a stronger genetic basis if you have an earlier age at onset." Nestadt is an associate professor of psychiatry and behavioral sciences at Johns Hopkins School of Medicine.
"It looks to be a pretty good study," Robert Hudak, MD, tells WebMD. "The findings [that OCD is a familial disorder] are not unexpected and it has been my experience too." He says he finds it very interesting that the younger the person is when they start manifesting symptoms, the higher the risk that family members will have it too.
This shows that, "early age of onset ... indicates there is a really strong genetic biologic component." Hudak, an assistant professor of psychiatry at the University of Pittsburgh Medical School, reviewed the study for WebMD.
In the study, researchers selected patients with OCD in the Baltimore and Washington, D.C., areas and compared them with people who did not have OCD. They then contacted family members and used various rating scales to determine if the study participants' relatives were affected, too.
The occurrence of OCD was almost five times higher among relatives of patients than among relatives of people who did not have OCD.
In addition, when the researchers looked at the age when symptoms occurred, they found that when the age of onset was 5 to 17 years, the occurrence of OCD in relatives was 13.8%, but it was 0% in patients whose symptoms began between ages 18 to 41.
"If we want to find a cause -- and we don?t have any clear cut causes for this condition -- we have to look somewhere," says Nestadt. "If we [can] show this is a familial condition, and hence derive the conclusion that it is a genetic condition, we [can] study genes and may find a gene or genes that may be causing this."
"The second thing is that families who suffer from this condition want to know if their children are going to have it." Because treatments are available for the condition, he adds, "... related to that, if you are a relative of someone with OCD and if you start exhibiting obsessional-like or compulsive-like behaviors, you may be more in tune with it or more ready to get treatment," he says.
"My opinion -- and we have already submitted grants to do this -- is that we ought to go out there and start looking at genes," says Nestadt. "There may be people that disagree with me."
Not Hudak. "I think the next step, and studies are going on now, is taking a look at specific genes," he says. "Studies like this are extremely helpful."