Obsessive Compulsive Disorder at Johns Hopkins

OCD family Study consists of two phases. In the first phase of the project, the major goal was to determine whether OCD occurs more frequently in certain families. We have concluded this first stage of the research project. Over 1100 individuals and 180 families participated in this phase. The major findings are:

    OCD occurs more frequently in certain families. Relatives of people with OCD are six times more likely to have OCD than are relatives of people without OCD. This finding, which is to be published in the Archives of General Psychiatry, provides strong evidence that OCD is familial and provides impetus for the scientific community to pursue genetic studies to identify potential genes for this disorder.

    OCD has an early age at onset; in fact, few individuals had an onset of symptoms after age 18. This is important for people to recognize so that children may be helped as soon as possible.

    People with OCD have anxiety and depression more often than individuals in the general population. These difficulties are amenable to treatment and should not be ignored.

Data from the interviews and questionnaires collected during the first phase of the project contributed to the publication of several scientific papers, which advances our knowledge and understanding of OCD. Summaries of several recently published papers are provided below.

   Hoarding in OCD
Hoarding is defined as excessive collecting or saving. This symptom was found to occur in about 30% of individuals with OCD, and in twice as many males as females. Differences were found between those who hoard and those who do not. Individuals who hoard tend to have a greater number of obsessions and compulsions. They tend to be at a younger age when they experience their first OCD symptoms. They are more likely to experience obsessions and compulsions involving counting, ordering, and the precise lining up of objects. Individuals with OCD who hoard are more likely to also experience excessive grooming difficulties, such as nail biting, hair pulling, and especially skin picking. We also found differences in the families of those who hoard and those who do not. Individuals who hoard were more likely to have close relatives who hoard and/or experience tics or uncontrollable muscle spasms. Overall, the results showed that hoarding appears to run in some families with OCD, and it may be involved in a particular subtype of the disorder.

   OCD, Anxiety, and Depression in Families
We found that close relatives of individuals with OCD were more likely to suffer from certain anxiety disorders and depression than in families without OCD. Some of these conditions, such as depression and panic attacks, may develop because of having OCD. For example, a person may get depressed because of feeling demoralized from living with OCD symptoms. Or someone may develop panic attacks that are related to the high anxiety of their obsessions. Therefore, it is important that OCD be identified and treated early so that the person is less likely to develop additional emotional difficulties. Two anxiety disorders were found to be unrelated to living with OCD symptoms and appear to run in families with OCD. These are generalized anxiety disorder (excessive worrying) and agoraphobia (avoiding places or not leaving home due to fears). Because these types of anxiety disorders run in families with OCD, it may be that anxiety is involved in the genes that make families vulnerable to OCD.

   A Major Gene for OCD?
Results from the OCD Family Study have provided strong evidence that a major gene is involved in the inheritance of OCD among family members. The gene is likely “dominant”, meaning only on parent needs to possess the gene in order for it to be passed on to a child. It also seems that females who possess the gene are more likely than males to actually develop OCD.

The second phase of this research project is actively in progress. We are asking families in which two or more individuals are affected by OCD to participate. This second phase began in 2000, and we plan to continue recruiting families to participate in this important part of the project. To date, over 500 families have volunteered to be interviewed and provide a sample of blood. The goal of this phase is to find genes that are associated with the development of OCD.

The third phase of the OCD Family Study has begun. Based on the blood samples of 300 families, we have conducted an initial DNA scan and have found regions on several chromosomes that are promising for finding genes that may predispose a person to OCD. This is still very initial work, and a lot of additional efforts are needed to hone in on a more specific gene or genes (It is important to recognize that no gene or marker for OCD has been identified as yet, and therefore no test has been developed; however, this is our future goal.) In order to facilitate this work, we continue to recruit eligible families. We believe that the larger the number of participating families, the higher the likelihood of finding something worthwhile. We share a hope with the participants that finding particular genes associated with the disorder will lead to better treatment approaches and prevention.