Phenotypic characteristics of Obsessive-Compulsive Disorder ascertained in adulthood

Over the past decade, the increased awareness and knowledge of Obsessive-Compulsive Disorder (OCD) has allowed the in-depth study of its phenotypic characteristics. The largest studies to date have described the symptom and syndrome characteristics of treatment-seeking patients. While usefully homogeneous with regard to their current state, the clinical characteristics of patients seeking treatment may only partially represent the OCD population. We report findings from 100 self-selected volunteers at various stages of their OCD illness who were participating in a genetic study. Many similarities with past reports were found, including high rates of mood disorder, significantly more mood disorder in females as compared with males, and increased social impairment among males despite an equal amount of time in episodes of disorder. On the other hand, mean age of onset in this nontreatment seeking population was younger. Lifetime rates of obsessions and compulsions in this population were substantially higher than previous reports, suggesting that the content of obsessions and compulsions shifted over time, and evolved into a lifetime repertoire. Furthermore, a separate analysis of the age of clinically significant O-C symptom onset without impairment revealed that males and females did not differ, suggesting that previous reports of earlier onset age in males may actually reflect earlier onset of impairment. Future genetic studies may benefit from the analysis of both significant O-C symptom onset, as well as the onset of full-syndromal OCD. These findings may suggest phenotypic characteristics that define homogeneous subgroups of patients with OCD.