Given the general population prevalence rates of obsessive compulsive disorder (OCD) and the affective disorders, one would expect the co-occurrence of these syndromes to be rare. Yet findings by our group and others have revealed extremely high rates of comorbidity in OCD with both depressive disorders (DD; 50%) and bipolar disorder (BPD; 10%). The current investigation sought to further clarify the role affective disorder comorbidity—particularly that with BPD—may play in the clinical expression of OCD.Method
A total of 605 individuals with OCD were evaluated with the Structured Clinical Interview for DSM-IV. The sample included three groups: BPD (bipolar I or II; N = 79, 13.1%), DD (major depression or dysthymia; N = 388, 64.1%), and NAD (no affective disorder comorbidity; N = 138, 22.8%). Group-wise comparisons were conducted on comorbidity patterns, impairment measures, and clinical features of OCD.Results
Analyses revealed a graded severity pattern, with the BPD group as the most severe, followed by the DD group, and finally the NAD group. Severity was reflected by the total number of Axis I disorders (P<.01), the number of psychiatric hospitalizations (P<.001), impairment measures (Ps<.05), and OCD symptoms (P<.01). It is worth noting that the impairment and OCD symptom severity findings were not attributable to the higher level of nonmood disorder comorbidities in the BPD and DD groups.Results
Those individuals with comorbid affective disorders, particularly BPD, represent a clinically severe group compared to those without such comorbidity. Clarifying the phenomenological features of OCD-affective disorder comorbidity has important etiological and treatment implications. Depression and Anxiety 0:1–8, 2011. © 2011 Wiley Periodicals, Inc.