Lifetime comorbidity of obsessive-compulsive disorder and sub-threshold obsessive-compulsive symptomatology in the community: impact, prevalence, socio-demographic and clinical characteristics

OBJECTIVE: This study aims to expand the available knowledge on Obsessive Compulsive Disorder (OCD)-comorbidity by investigating the prevalence and clinical impact on a group of individuals with OCD or subthreshold OC syndrome (OCS), prospectively followed-up over an extended period. METHODS: A stratified sample of the general population of the canton of Zurich, Switzerland (n = 591), participated in a series of seven interviews over a 30-year period. Clinically significant comorbid subgroups of OCD/OCS were compared to cases of OCD/OCS without respective comorbidity, in order to determine differences in socio-demographic and other clinical characteristics. RESULTS: Lifetime rates of psychiatric comorbidity were high and increased in prevalence across the OC severity spectrum. Bipolar affective disorder was significantly associated with OCD whereas unipolar major depression and both alcohol and drug misuse disorders were not. Most forms of comorbidity increased distress and impacted negatively on family and work relationships, though disorder-specific effects were observed. Thus, agoraphobia and GAD were associated with increased OCD-severity; bipolar disorder was associated with suicidal acts and panic disorder increased treatment-seeking behaviour. CONCLUSIONS: Despite the statistical limitations imposed by the small sample-size, our findings highlight the negative impact of psychiatric comorbidity on health and psychosocial function.