Concomitant obsessive-compulsive disorder and schizotypal personality disorder

Despite advances in the management of patients with obsessive-compulsive disorder, some remain refractory to treatment. The authors retrospectively examined characteristics of 43 treatment-resistant obsessive-compulsive patients and found that those with concomitant schizotypal personality disorder had an extremely high rate of treatment failure. Of the 29 treated nonschizotypal patients, 26 (90%) improved at least moderately; only one of 14 (7%) schizotypal patients improved. In addition, the number of schizotypal features in each patient was strongly negatively correlated with treatment outcome.