Obsessive-compulsive symptoms in a randomized, double-blind study with olanzapine or risperidone in young patients...

The prevalence of obsessive-compulsive symptoms (OCS) in patients with schizophrenia is relatively high. Antipsychotics have been found to influence OCS.

To determine whether induction or severity of OCS differs during treatment with olanzapine or risperidone in young patients with early psychosis.

One hundred twenty-two patients with a Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition diagnosis of schizophrenia, schizoaffective disorder, or schizophreniform disorder were randomized in a double-blind design to groups of 6 weeks' treatment with olanzapine (n = 59) or risperidone (n = 63), with a mean dose of 11.3 mg olanzapine and 3.0 mg risperidone at 6 weeks. Primary outcome measures were the mean baseline-to-endpoint change in total score on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS).

Treatment with olanzapine was associated with greater decreases in Y-BOCS total score than treatment with risperidone in total group (N = 122: -2.2 vs -0.3, z = -2.651, P < 0.01), in patients with baseline Y-BOCS total score greater than 0 (n = 58: -5.1 vs -0.4, z = -2.717, P < 0.01), and in patients with baseline Y-BOCS total score greater than 10 (n = 29: -7.1 vs -0.6, z = -2.138, P = 0.032).

In this randomized, 6-week, double-blind trial, we found a significant and clinically relevant difference in decrease in Y-BOCS scores favoring olanzapine compared with risperidone.