Aripiprazole in Schizophrenia Patients With Comorbid Obsessive-Compulsive Symptoms: An Open-Label Study of 15 Patients

Background: Approximately 15% of patients with schizophrenia also meet DSM-IV criteria for obsessive-compulsive disorder (OCD) at some point in their illness, a rate considerably higher than in the general population. This study examined aripiprazole treatment of patients with comorbid schizophrenia and obsessive-compulsive symptoms (OCS) that did not meet full criteria for OCD.

Method: Physically healthy adults aged 18 to 65 years with DSM-IV schizophrenia and a minimum score of 16 on the Yale-Brown Obsessive Compulsive Scale (YBOCS) were eligible to participate in this 6-week, open-label, flexible-dose trial of aripiprazole monotherapy. Patients currently taking another antipsychotic medication were concurrently down-titrated from their current antipsychotic and up-titrated with aripiprazole, starting with 15 mg/day. Coadministration of the 2 medications lasted from 7 to 14 days, until a stable therapeutic dose of 10 to 30 mg/day was reached. Subjects were recruited into the study, which was conducted at the Schizophrenia Clinic of Stanford University School of Medicine, between January 2005 and December 2006.

Results: Of 15 eligible patients, 7 completed the trial. All 7 had at least minimal improvement on the YBOCS, the Clinical Global Impressions (CGI) scale, and the Positive and Negative Syndrome Scale (PANSS). At week 6, the mean CGI-Improvement scale score was 2.3 (much improved). Mean PANSS scores decreased from 75 to 56, a mean decrease of 21%, (p < .05). On the YBOCS, 6 of 7 completers showed a change of greater than 35% from baseline to week 6.

Conclusion: These results suggest that aripiprazole monotherapy can modestly improve the outcome for some schizophrenia patients with obsessive-compulsive symptoms. Further studies with aripiprazole under controlled conditions are indicated for this population of patients. Overall, even modest improvement in global functioning due to an improvement in an OCS component may be clinically meaningful for this difficult-to-treat subset of schizophrenia patients.