The use of psychopharmacological agents in a sample of patients with obsessive-compulsive disorder and their relationship to symptoms

Background: Obsessive-compulsive disorder (OCD) is recognised as a heterogeneous disorder in which only 40 to 60% respond to pharmacological interventions [1]. Numerous factor analytic studies have supported the concept of symptom dimensions [2]. Furthermore, there is some evidence to suggest that OCD symptom may respond differently to treatment [3]. Objective: To report prescribing habits among doctors in Australia for a sample of patients with OCD and to ascertain whether prescribing habits were associated with specific symptoms of OCD. Method: 151 patients with OCD were asked what medication they were taking on entering the Nepean OCD Study. They also had their OCD symptoms assessed with the Yale- Brown Obsessive-Compulsive Scale (Y-BOCS) and the Vancouver Obsessive-Compulsive Inventory (VOCI). The severity of patients' illness was assessed with the Y-BOCS total score, Clinical Global Impression (CGI) score and Sheehan Disability Scale (SDS). Correlations and logistic regression were used to assess for prescribing patterns in association with symptom severity, disability, Y-BOCS symptom factors and VOCI symptom subscales. Results: More than half (60.5%, n = 91) of the sample were taking psychopharmacological agents. Of those taking psychopharmacological agents, selective serotonin reuptake inhibitors (SSRI) were prescribed in 58.2% (n = 53) of cases. Other psychopharmacological agents included: second generation antipsychotic medication 24.2% (n = 22); serotonin noradrenaline reuptake inhibitors (SNRI) 16.5% (n = 15); tricyclic antidepressants 16.5% (n = 15); and benzodiazepines 13.2% (n = 12). Of the antidepressants, the most commonly prescribed were: fluoxetine 14.3% (n = 13); clomipramine 12.1% (n = 11); sertraline 12.1% (n = 11); venlafaxine 12.1% (n = 11); escitalopram 9.9% (n = 9); fluvoxamine 8.9% (n = 8) and citalopram 7.7% (n = 7). Vitamins were taken by 47.3% (n = 43) of patients. Use of any psychopharmacological agent was associated with higher Y-BOCS scores (r = 0.235, p = 0.004), higher CGI scores (r = 0.351, p = 0.000), higher SDS work (r = 0.394, p = 0.000) and higher SDS social (r = 0.307, p = 0.000). The same pattern of association with OCD severity and disability was found for SSRIs and antipsychotics, but not clomipramine. SSRI use was associated with VOCI contamination symptom subscale scores (r = 0.194, p = 0.019) and VOCI obsessions subscale scores (r = 0.174, p = 0.036). The use of antipsychotics was correlated with VOCI obsessions subscale scores (r = 0.226, p = 0.006) and VOCI indecisiveness subscale scores (r = 0.169, p = 0.043). The VOCI hoarding symptom subscale was negatively correlated with psychopharmacological agents (r = −0.184, p = 0.027) and in particular clomipramine (r = −0.211, p = 0.011). This pattern was also seen with the Y-BOCS hoarding factor (OR = 0.74, p = 0.011). Conclusions: Patients with OCD are commonly prescribed antidepressants and second generation antipsychotics. Prescription of psychopharmacological agents was generally associated with more severe illness and a greater level of disability. OCD symptoms were associated with different patterns of psychopharmacological agent use. Hoarders were less likely to receive medication. Patients with more prominent obsessions appear to have been taking psychopharmacological agents and in particular antipsychotic agents more frequently. This study adds support to efforts to subtype OCD according to its symptoms.