Harm avoidance in subjects with obsessive-compulsive disorder and their families.

Introduction: This study investigates the role of harm avoidance (HA) as a possible risk factor in the familiality of obsessive-compulsive disorder (OCD). HA is considered to be a genetically influenced personality trait with an increasingly understood neuroanatomical basis.
Method: 75 subjects with OCD from hospital sites and a community sample and their 152 first degree relatives and 75 age and sex matched controls with their 143 first degree relatives were evaluated with structured clinical interviews (DSM-IV). HA was assessed with Cloninger's Tridimensional Personality Questionnaire (TPQ).
Results: Subjects with OCD had higher scores of HA than controls (p<or=0.001). First degree relatives of OCD cases also showed higher HA than relatives of control subjects (p=0.001).These results remained stable when comparing only OCD subjects versus controls (p<or=0.001) and relatives of OCD cases versus relatives of controls (p=0.005) without current comorbid disorders.
Limitations: The investigation of HA alone does not allow to disentangle the transmission of biological versus psychological factors related to an elevated level of anxiety in families of OCD cases.
Conclusion: This is the first study to extent previous findings of elevated HA in OCD cases to their first degree relatives. Thus, HA may partially mediate the familial risk for OCD.