Symptom subtypes of obsessive-compulsive disorder: are they relevant for treatment?

Several symptom subtypes of obsessive-compulsive disorder (OCD) have been identified on the basis of the predominant obsessions and compulsions. The objectives of the present article were to review the literature on the relationship between OCD symptom subtypes and treatment response and to suggest strategies that might assist with the choice of treatment and improve treatment outcome in patients with various subtypes. An extensive literature search was performed, relevant studies were identified, and their results reported. Overt compulsions were generally associated with a relatively good response to the behaviour therapy technique of exposure and response prevention (ERP) and with poorer response to serotonin re-uptake inhibitors (SRIs). Washing/cleaning and checking compulsions tend to respond well to ERP, whereas the majority of studies show that washing/cleaning compulsions are associated with a poorer response to SRIs. Most studies suggest that patients with the symmetry, ordering and arranging subtype do not fare worse with ERP and SRIs than patients with other symptom subtypes. Some studies suggested that obsessions might respond to SRIs somewhat better than to ERP. In the majority of the studies, hoarding and the subtype characterized by sexual or religious obsessions and absence of overt compulsions ('pure obsessions') have been associated with poor response to ERP and SRIs. It was concluded that treatment strategies cannot be precisely tailored to OCD symptom subtypes. Many other factors influence the outcome of treatment and need to be considered along with the symptom subtypes when making decisions about treatment. While ERP and SRIs remain the mainstay of treatment regardless of the symptom subtype, the addition of cognitive therapy techniques and/or antipsychotic medications may enhance treatment response in the presence of certain features discussed in the article.