There is a significant body of research supporting the efficacy and effectiveness of CBT incorporating exposure and response prevention (ERP) for the treatment of OCD as a single disorder [760-768], including two reviews – one systematic and one meta-analysis [769, 770]. Research has found that the effect sizes for ERP are as large as pharmacological treatments [765], with lower rates of relapse [766, 771, 772]. As such, CBT incorporating ERP is recommended as a first line of treatment for single disorder OCD by clinical practice guidelines [773-775].
ERP involves repeated, prolonged and systematic confrontation with certain objects or situations that trigger obsessional responses (exposure), and resisting the compulsive urges that arise in response to the triggers (response prevention) [776]. The nature of the exposure therapy can be in vivo (i.e., physically touching a light switch) or in the imagination (i.e., confronting images of loved ones dying). ERP concurrently weakens the association between the obsessional triggers and anxiety arousal, and compulsive rituals and anxiety reduction (i.e., ERP seeks to weaken the idea that anxiety will only reduce once compulsions are performed [777]). Additional cognitive therapy can help clients address thought patterns that may be underlying their obsessional fear [776]. Although ERP is considered to be the treatment of choice for OCD [775, 778], it has been suggested that the efficacy is highly dependent on ERP being delivered consistent with clinical guidelines [778].
The UK NICE guidelines recommend that low intensity CBT with ERP (i.e., consisting of up to 10 practitioner hours per client) be offered to clients with mild functional impairment and those who express a preference for a low intensity approach [775]. Low intensity treatments may include brief individual CBT with ERP, using structured self-help materials; brief individual CBT with ERP by telephone; or group CBT. Those with mild functional impairment who are unable to engage in low intensity CBT, or have a proven inadequate response to low intensity treatment, should be offered a choice of either a course of SSRI or more intensive CBT with ERP (i.e., more than 10 practitioner hours per client), as these treatments have been shown to have comparable efficacy. Similarly, the UK NICE guidelines recommend that people with OCD with moderate functional impairment should be offered a choice between SSRIs or more intensive CBT with ERP [775]. Despite evidence of its efficacy, ERP is not always the first line of treatment provided to clients with OCD. This is likely due to a combination of factors, including the ease with which medication is prescribed and is available over ERP; the fact that many workers are either unfamiliar with, or reluctant to perform ERP; and the reluctance of some people with OCD to engage with ERP due to the anxiety-evoking nature of the treatment [769].
There are currently no integrated treatments for co-occurring OCD and AOD use disorders and only one RCT has examined the concurrent treatment of OCD among people attending residential rehabilitation for their AOD use [779]. Clients who received concurrent ERP for their OCD remained in treatment longer, and had lower OCD symptom severity and higher abstinence rates during treatment and at the 12-month follow-up, compared to those who received AOD treatment alone or AOD use plus progressive muscle relaxation. Based on the evidence provided from this RCT [779], and evidence pertaining to the treatment of OCD and AOD use as single disorders, Klostermann and Fals [759] recommend five steps for treating people with comorbid OCD and AOD use. The five steps include:
- Assessment of both OCD and AOD use: This can be difficult if clients are attempting to conceal their symptoms for fear of embarrassment, and OCD can often be confused with other psychiatric illnesses (e.g., phobia, depression, and psychosis).
- Assessment of symptom type and quality using validated assessment tools: For example intrusive thoughts, feelings and behaviours, detailed description of the anxiety-provoking stimuli typically experienced, and the ritualistic behaviours performed in response.
- Psychoeducational therapy.
- Creation of a stimulus hierarchy: Listing obsessions, compulsions and anxiety-provoking stimuli, which are then rated based on the amount of anxiety generated.
- Treatment: Concurrent delivery of ERP and AOD use treatment.
Although the findings of Fals-Stewart and Schafer [779] are promising, more evidence is clearly needed. In particular, the cyclical nature between OCD and AOD use suggests there is a need for the development of integrated treatments that simultaneously address both disorders [769, 780]. Stewart and O’Connor [780] suggest that such an integrated approach may consist of psychoeducation to explore the cyclical relationship between OCD symptoms and AOD use; targeting AOD use during ERP treatment if it is identified as a safety behaviour (a behaviour that temporarily relieves the distress associated with obsessions); and therapeutic work focused on increasing self-efficacy, in order to help the client believe they can cope without AOD use [780].