A Cochrane review [947] of RCTs examining psychosocial treatments for co-occurring severe mental illness (predominantly psychotic spectrum disorders) and AOD use concluded that there is no clear evidence supporting the use of any one approach to psychological treatment over standard care, with many studies reporting mixed findings. The authors note, however, that it is difficult to draw any firm conclusions from the current evidence base due to methodological differences between studies. The only clear finding was an association between MI and greater reductions in alcohol use relative to standard care [947].
Barrowclough and colleagues [948] suggest that MI techniques may need to be adapted for clients with psychotic disorders because disorganised thoughts and speech may make it difficult for AOD workers to understand what the client is trying to say, and psychotic symptoms (combined with AOD use and heavy medication regimes) may impair clients’ cognitive abilities. For this reason, it is recommended that therapists:
- Make use of more frequent and shorter reflections to clarify meaning.
- Use frequent and concise summaries to draw together information.
- Avoid emotionally salient material that is likely to increase thought disorder.
- Provide sufficient time for the client to respond to reflections and summaries.
- Ask simple open questions and avoid multiple choices or complicated language.
While acknowledging the lack of robust evidence, in addition to MI, the Royal Australian and New Zealand College of Psychiatry (RANZCP) guidelines for the management of schizophrenia and related disorders nonetheless recommend the use of integrated therapies that combine CBT, lifestyle interventions and case management for the treatment of co-occurring schizophrenia and AOD use [444].
CBT for psychosis is a well-recognised evidence-based treatment for symptoms of psychosis [444]. Several studies have examined the efficacy of CBT on symptoms of psychosis and AOD use [949, 950]; again, evidence regarding the efficacy of CBT in treating co-occurring psychotic disorders and AOD problems is mixed. Naeem and colleagues [950] found that although CBT led to better outcomes for symptoms of psychopathology, there were no differences between CBT and treatment as usual groups on AOD use outcomes. Similarly, Edwards and colleagues [949] found no significant differences between the CBT and psychoeducation groups for the key outcomes of cannabis use or psychopathology.
Recent research has identified assertive community outreach as one integrated approach that may be particularly beneficial for clients with co-occurring psychosis and AOD use. Assertive community outreach utilises specialised outreach teams to provide integrated and intensive treatment within a community setting (e.g., the client’s home), and includes mental health treatment, housing support, and rehabilitation [951]. Several studies examining the effectiveness of assertive community outreach for people with co-occurring psychosis and AOD use have found improvements in psychotic symptoms [952, 953], reduced frequency of AOD use [954], improved housing stability [952, 955, 956], fewer hospital readmissions [952, 957], improved psychological wellbeing [955], and general functioning [956] relative to baseline and treatment as usual control conditions.
Recent research has also demonstrated that, relative to standard care for psychosis and co-occurring AOD use, skills-based training and peer supported social activities delivered alongside standard care, leads to improved outcomes in relation to symptoms of psychosis, AOD use, as well as functional outcomes [958]. Cognitive remediation therapy has also been found to be beneficial in addressing cognitive and functional deficits (e.g., relating executive function, attention, memory, social cognition) among people with psychotic disorders [959] and shows promise as an adjunctive treatment for people receiving AOD treatment [960]; however, research among people experiencing both conditions is in its infancy [961].
Contingency management may also be a useful adjunct to other treatments for psychotic spectrum disorders and AOD use. As discussed in Chapter B6, contingency management involves the use of reinforcement to encourage particular behaviours (and discourage undesired behaviours). A metaanalysis examining the effect of contingency management for people with co-occurring psychotic and AOD use disorders concluded that contingency management improves abstinence from AOD use, although effects on psychotic symptoms were not examined [962]. These findings are consistent with a review of earlier research [963].
The popularity of mindfulness-based interventions has increased in recent years. To date, however, no studies have evaluated mindfulness in the context of co-occurring psychosis and AOD use. Studies of single disorder psychosis have found mindfulness beneficial in reducing both negative [964, 965] and positive psychotic symptoms [965]; and mindfulness has been found to reduce the frequency and amount of AOD use, AOD-related problems [966], cravings [754, 966], and depressive symptoms [754], relative to control groups (which included treatment as usual, CBT, and support groups), among people with AOD use disorders as single disorders. Together these findings suggest that mindfulness may be beneficial for people experiencing both conditions.