Pharmacotherapy in paediatric obsessive-compulsive disorder: a naturalistic, retrospective study.

BACKGROUND: Pediatric obsessive-compulsive disorder (OCD) can cause substantial impairment in academic, social and family functioning. Even though cognitive-behavioural therapy (CBT) is an effective treatment, the pharmacological option has to be taken into consideration. Effectiveness of serotonin reuptake inhibitors (SRIs) has been supported by several double-blind, placebo-controlled studies. OBJECTIVE: To report the response to pharmacotherapy in children and adolescents with OCD naturalistically followed up and treated with SRIs. METHODS: From a consecutive series of 257 patients (174 males and 83 females; mean age 13.6+/-2.7 years) diagnosed with OCD following a clinical interview according to DSM-IV criteria, 37 children improved significantly after psychotherapy and were excluded. The remaining 220 patients were included in the study. RESULTS: Eighty-nine patients (40.5%) were managed with SRI monotherapy and 131 with an SRI in combination with another medication. Compared with those who needed polypharmacy, patients managed with SRI monotherapy were younger at the time of the first consultation, had less severe symptoms at baseline, and more frequently presented with co-occurring anxiety and depressive disorders, while patients receiving polypharmacy presented with higher rates of bipolar disorder, tic disorder and disruptive behaviour disorders. 135 patients (61.4%) achieved a positive clinical response and were considered responders. When differences between responders and nonresponders at the end of follow-up were considered, irrespective of the pharmacological treatment (monotherapy or polypharmacy), responders had less severe disease at baseline, were younger at the time of the first consultation, more frequently presented with the contamination/cleaning phenotype and less frequently presented with the hoarding phenotype. Treatment refractoriness was associated with higher rates of conduct disorder and bipolar disorder, and lower rates of generalized anxiety disorder and panic disorder. Forty-three children received therapy with an atypical antipsychotic as an augmenting strategy, and 25 of these children (58.1%) became responders. Responders to augmentation were less severely impaired at baseline, while different subtypes of OCD were similar between responders and nonresponders, as were patterns of co-morbidity. CONCLUSION: Our study suggests that putative variables associated with response to pharmacological treatment of paediatric OCD can be defined, and can help improve treatment strategies.