The efficacy of acceptance and commitment therapy (ACT) in psychosis has been reported but not for medication-resistant psychosis.

To test the efficacy of ACT in a sample of community-residing patients with persisting psychotic symptoms. (Australian New Zealand Clinical Trials Registry: ACTRN12608000210370.)

The primary outcome was overall mental state at post-therapy (Positive and Negative Syndrome Scale –total); secondary outcomes were psychotic symptom dimensions and functioning. In total, 96 patients were randomised to ACT (n = 49) or befriending (n = 47). Symptom, functioning and process measures were administered at baseline, post-therapy and 6 months later.

There was no group difference on overall mental state. In secondary analyses the ACT group showed greater improvement in positive symptoms and hallucination distress at follow-up: Cohen's d = 0.52 (95% CI 0.07–0.98) and 0.65 (95% CI 0.24–1.06), respectively.

Improvements reflected the treatment focus on positive symptoms; however, absence of process-measure changes suggests that the ACT intervention used did not manipulate targeted processes beyond befriending. Symptom-specific therapy refinements, improved investigation of process and attention to cognitive functioning and dose are warranted in future research.

To evaluate the effect of N-acetylcysteine (NAC) on substance use in a double-blind, placebo-controlled trial of NAC in bipolar disorder. It is hypothesised that NAC will be superior to placebo for reducing scores on the Clinical Global Impressions scale for Substance Use (CGI-SU).

Participants were randomised to 6-months of treatment with 2 g/day NAC (n = 38) or placebo (n = 37). Substance use was assessed at baseline using the Habits instrument. Change in substance use was assessed at regular study visits using the CGI-SU.

Amongst the 75 participants 78.7% drank alcohol (any frequency), 45.3% smoked tobacco and 92% consumer caffeine. Other substances were used by fewer than six participants. Caffeine use was significantly lower for NAC-treated participants compared with placebo at week 2 of treatment but not at other study visits.

NAC appeared to have little effect on substance use in this population. A larger study on a substance using population will be necessary to determine if NAC may be a useful treatment for substance use.

To evaluate the effect of N-acetylcysteine (NAC) on substance use in a double-blind, placebo-controlled trial of NAC in bipolar disorder. It is hypothesised that NAC will be superior to placebo for reducing scores on the Clinical Global Impressions scale for Substance Use (CGI-SU).

Participants were randomised to a 6-months of treatment with 2 g/day NAC (n = 38) or placebo (n = 37). Substance use was assessed at baseline using a Habits instrument. Change in substance use was assessed at regular study visits using the CGI-SU.

Among the 75 participants 78.7% drank alcohol (any frequency), 45.3% smoked tobacco and 92% consumed caffeine. Other substances were used by fewer than six participants. Caffeine use was significantly lower for NAC-treated participants compared to placebo at week 2 of treatment but not at other study visits.

NAC appeared to have little effect on the participants who were using substances. A larger study on a substance-using population will be necessary to determine if NAC may be a useful treatment for substance use.

To date evidence of the relationship between cognition and Aβ amyloid during the early stages of Alzheimer's Disease (AD) has been inconsistent. This study aimed to describe the nature and magnitude of the relationship between Aβ amyloid and cognitive performance of individuals without dementia.

Composite cognitive measures were developed from the Australian Imaging Biomarkers and Lifestyle study neuropsychological test battery using data from 768 healthy older adults and 133 adults with mild cognitive impairment (MCI). A subgroup of this sample (174 healthy, 53 MCI) underwent neuroimaging for Aβ amyloid.

Within the MCI group individuals with high Aβ amyloid showed selective impairment for memory compared with those with low Aβ amyloid; however, this difference was not evident in the healthy group.

The current findings provide further evidence of the relationship between Aβ amyloid and cognition, with memory impairment being the primary symptom of the underlying disease during the prodromal phases of AD.