Cannabis use and misuse prevalence among people with psychosis

Background: Increasing attention has been given by researchers to cannabis use in individuals with psychosis. As psychoses are relatively low-prevalence disorders, research has been mostly been restricted to small-scale studies of treatment samples.The reported prevalence estimates obtained from these studies vary widely. Aims: To provide prevalence estimates based on larger samples and to examine sources of variability in prevalence estimates across studies. Method: Data from 53 studies of treatment samples and 5 epidemiological studies were analysed. Results: Based on treatment sample data, prevalence estimates were calculated for current use (23.0%), current misuse (11.3%),12-month use (29.2%),12-month misuse (18.8%), lifetime use (42.1%) and lifetime misuse (22.5%). Epidemiological studies consistently reported higher cannabis use and misuse prevalence in people with psychosis. Conclusions: The factor most consistently associated with increased odds of cannabis prevalence was specificity of diagnosis. Factors such as consumption patterns and study design merit further consideration.

Natural recovery from cannabis use in people with psychosis: A qualitative study

- Objective There is rapidly growing evidence of natural recovery from cannabis use in people with psychosis, but little is known about how it occurs. This qualitative study explores what factors influence the decision to cease cannabis use, maintain cessation, and prevent relapse. - Methods Ten people with early psychosis and lifetime cannabis misuse, who had been abstinent for at least a month, were recruited from public adult mental health services. These six men and four women participated in a semi-structured qualitative interview assessing reasons for addressing cannabis use, effective change strategies, lapse contexts, and methods used to regain control. Interpretative phenomenological analysis was used to identify themes in their responses. - Results Participants had a mean age of 23 years (SD = 3.7), started using cannabis at age 13.7 (SD = 1.6), began daily use at 17 (SD = 3.1), and had abstained from cannabis for 7.9 months (SD = 5.4). Awareness of the negative impact of substance use across multiple domains and the presence of social support for cannabis cessation were seen as vital to sustained success, as was utilization of a combination of coping strategies. The ability to address pressure from substance-using peers was commonly mentioned. - Conclusions Maximally effective treatment may need to focus on eliciting a range of benefits of cessation and control strategies and on maximizing both support for change and resistance to peer pressure. Further research might focus on comparing perceived effective strategies between individuals who obtain sustained cessation versus those who relapse.

Demographic and clinical correlates of comorbid substance use disorders in psychosis : multivariate analyses from an epidemiological sample

Background: While there has been substantial research examining the correlates of comorbid substance abuse in psychotic disorders, it has been difficult to tease apart the relative importance of individual variables. Multivariate analyses are required, in which the relative contributions of risk factors to specific forms of substance misuse are examined, while taking into account the effects of other important correlates. Methods: This study used multivariate correlates of several forms of comorbid substance misuse in a large epidemiological sample of 852 Australians with DSMIII- R-diagnosed psychoses. Results: Multiple substance use was common and equally prevalent in nonaffective and affective psychoses. The most consistent correlate across the substance use disorders was male sex. Younger age groups were more likely to report the use of illegal drugs, while alcohol misuse was not associated with age. Side effects secondary to medication were associated with the misuse of cannabis and multiple substances, but not alcohol. Lower educational attainment was associated with cannabis misuse but not other forms of substance abuse. Conclusion: The profile of substance misuse in psychosis shows clinical and demographic gradients that can inform treatment and preventive research.

Does the addition of integrated cognitive behaviour therapy and motivational interviewing improve the outcomes of standard care for young people with comorbid depression and substance misuse?

Background: The high rates of comorbid depression and substance use in young people have been associated with a range of adverse outcomes. Yet, few treatment studies have been conducted with this population. Objective: To determine if the addition of Motivational Interviewing and Cognitive Behaviour Therapy (MI/CBT) to standard alcohol and other drug (AOD) care improves the outcomes of young people with comorbid depression and substance use. Participants and Setting: Participants comprised 88 young people with comorbid depression (Kessler 10 score of > 17) and substance use (mainly alcohol/cannabis) seeking treatment at two youth AOD services in Melbourne, Australia. Sixty young people received MI/CBT in addition to standard care (SC) and 28 received SC alone. Outcomes Measures: Primary outcome measures were depressive symptoms and drug and alcohol use in the past month. Assessments were conducted at baseline, 3 and 6 months follow up. Results and Conclusions: The addition of MI/CBT to SC was associated with a significantly greater rate of change in depression, cannabis use, motivation to change substance use and social contact in the first 3 months. However, those who received SC had achieved similar improvements on these variables by 6 months follow up. All young people achieved significant improvements in functioning and quality of life variables over time, regardless of the treatment group. No changes in alcohol or other drug use were found in either group. The delivery of MI/CBT in addition to standard AOD care may offer accelerated treatment gains in the short-term.

Substance use and misuse in burn patients: testing the classical hypotheses of the interaction between posttraumatic symptomatology and substance use

Background: We aimed to test whether the three classical hypotheses of the interaction between posttraumatic symptomatology and substance use (high risk of trauma exposure, susceptibility for posttraumatic symptomatology, and self-medication of symptoms), may be useful in the understanding of substance use among burn patients. Methods: We analysed substance use data (nicotine, alcohol, cannabis, amphetamines, cocaine, opiates, and tranquilizers) and psychopathology measures among burn patients admitted to a Burns Unit and enrolled in a longitudinal observational study. Lifetime substance use information (n = 246) was incorporated to analyses aiming to test the high risk hypothesis. Only patients assessed for psychopathology in a six months follow-up (n = 183) were included in prospective analyses testing the susceptibility and self-medication hypotheses. Results: Regarding the high risk hypothesis, results show a higher proportion of heroin and tranquilizer users compared to the general population. Furthermore, in line with the susceptibility hypothesis, higher levels of symptomatology were found in lifetime alcohol, tobacco and drug users during recovery. The self-medication hypothesis could be tested partially due to the hospital stay “cleaning” effect, but severity of symptoms was linked to caffeine, nicotine, alcohol and cannabis use after discharge. Conclusions: We found that the three classical hypotheses could be used to understand the link between traumatic experiences and substance use explaining different patterns of burn patient’s risk for trauma exposure and emergence of symptomatology.

Cannabis use and related harms in the transition to young adulthood: a longitudinal study of Australian secondary school students

The current study documents the changing rates of cannabis use, misuse and cannabis-related social harms among Australian adolescents as they grow into young adulthood. It utilised data from a longitudinal study of young people at ages 15, 16, 17, and 19. The rates of cannabis use were found to increase as participants aged; past year use increased from 7.5% at age 15 to 29.8% at age 19. Further, at ages 17 and 19, cannabis use was more prevalent among males than females. Among those who reported cannabis use, the rates of cannabis-related harms were low to moderate, and did not increase with age in the same manner as rates of cannabis use. The most prevalent self-reported cannabis-related harm was anxiety/depression; affecting between 20–30% of the cannabis users at each age. These findings may assist in understanding the extent of cannabis-related problems among youth, and in planning relevant services.

Course of substance misuse and daily tobacco use in first-episode psychosis

Background: Study of the course of substance misuse and daily tobacco use in first-episode psychosis may enhance detection and treatment of these substance-related problems. Methods: This 15-month follow-up study examined the course of substance misuse and daily tobacco use in 103 individuals treated for first-episode psychosis. Results: Three-quarters (72.6%) of patients with lifetime substance misuse, or half (51.5%) of all patients, continued substance misuse (primarily cannabis) during the 15-month follow-up period. There was a significant reduction in the rate of any substance misuse (70.9% versus 53.4%) but not daily tobacco use (76.7% versus 75.7%) between baseline and 15-month follow-up. Patients who continued substance misuse showed a significant reduction in the severity and frequency of substance use between baseline and follow-up. Patients who continued substance misuse were more likely to be younger, male and single, less likely to have completed secondary school, and more likely to have had more severe cannabis use prior to entry to treatment compared to patients who ceased substance misuse. Discussion: A significant proportion of young patients treated for first-episode psychosis are at risk of mental and physical health problems associated with substance misuse and/or regular tobacco use. (c) 2005 Elsevier B.V. All rights reserved.

Current evidence on integrated treatment for serious mental disorder and substance misuse

Substance misuse in people with serious mental disorders is common and has a wideranging negative impact. The multiplicity of problems suggests that this comorbidity is better conceptualized as a type of complex disorder than by ‘dual diagnosis’. Problems with sequential and parallel treatments have led to the development of integrated approaches, with one practitioner or team addressing both the substance use and mental disorder. These treatments are typically characterized by motivation enhancement, minimizing treatment-related stress, emphasizing harm reduction as well as abstinence, and assertive outreach. A review of published randomized trials demonstrates that superior effects to controls are rarely consistent across treatment foci and over time. While motivational interventions assist engagement, more intervention is usually required for integrated treatment programs to improve long-term outcomes more than control conditions. More intensive case management does not consistently improve impact, but extended cognitive-behavioral therapies have promise. Suggestions for maximizing treatment effects and improving research evidence are provided.

Predictors of cannabis use in men with and without psychosis

Background: Factors associated with cannabis use among people with psychosis are not well understood. ----- Aims: To examine whether people with psychosis and age-matched controls modified cannabis use in response to recent experiences. ----- Method: This study predicted 4 weeks of cannabis use prospectively, using expectancies derived from recent occasions of use. ----- Results: People with psychosis used cannabis less frequently than controls, but had more cannabis-related problems. More negative cannabis expectancies resulted in less frequent cannabis use over Follow-up. The psychosis group was more likely to moderate cannabis use after negative effects than controls. ----- Conclusions: Results offer optimism about abilities of people with psychosis tomoderate cannabis use in the short term.

A brief motivational intervention for substance misuse in recent-onset psychosis

Substance misuse is common in early psychosis, and impacts negatively on outcomes. Little is known about effective interventions for this population. We report a pilot study of brief intervention for substance misuse in early psychosis (Start Over and Survive: SOS), comparing it with Standard Care (SC). Twenty-five in-patients aged 18-35 years with early psychosis and current misuse of non-opioid drugs were allocated randomly to conditions. Substance use and related problems were assessed at baseline, 6 weeks and 3, 6 and 12 months. Final assessments were blind to condition. All 13 SOS participants who proceeded to motivational interviewing reported less substance use at 6 months, compared with 58% (7/12) in SC alone. Effects were well maintained to 12 months. However, more SOS participants lived with a relative or partner, and this also was associated with better outcomes. Engagement remained challenging: 39% (16/41) declined participation and 38% (5/13) in SOS only received rapport building. Further research will increase sample size, and address both engagement and potential confounds.

Reasons for cannabis use in men with and without psychosis

Psychoses are relatively low prevalence disorders that have a disproportionately negative impact on individuals and society. Cannabis use is one factor that can exacerbate the negative consequences associated with psychotic disorders. Relatively few studies have examined the effects or reasons for using cannabis self-reported by individuals with psychosis. The present study is the first known to compare directly such factors in individuals with and without psychosis, within a single study. At baseline and follow-up participants with psychosis most commonly reported using cannabis for positive mood alteration (36% and 42%), coping with negative affect (27% and 29%) and for social activity reasons (38% and 29%). The control group most commonly reported using cannabis for relaxation (34% and 43%) and social activity reasons (49% and 51%). Participants with psychosis were less likely to report relaxation as the most important effect after use (27%) or expect it at follow-up (49%) compared to the control group (53% and 70%). In both groups, addiction and positive affect enhancement were the composite variable scores correlated most consistently with concurrent amount and frequency of use.

Contrasting views and experiences of health professionals on the management of comorbid substance misuse and mental disorders

Objectives: To determine opinions and experiences of health professionals concerning the management of people with comorbid substance misuse and mental health disorders. Method: We conducted a survey of staff from mental health services and alcohol and drug services across Queensland. Survey items on problems and potential solutions had been generated by focus groups. Results: We analysed responses from 112 staff of alcohol and drug services and 380 mental health staff, representing a return of 79% and 42% respectively of the distributed surveys. One or more issues presented a substantial clinical management problem for 98% of respondents. Needs for increased facilities or services for dual disorder clients figured prominently. These included accommodation or respite care, work and rehabilitation programs, and support groups and resource materials for families. Needs for adolescent dual diagnosis services and after-hours alcohol and drug consultations were also reported. Each of these issues raised substantial problems for over 70% of staff. Another set of problems involved coordination of client care across mental health and alcohol and drug services, including disputes over duty of care. Difficulties with intersectoral liaison were more pronounced for alcohol and drug staff than for mental health. A majority of survey respondents identified 13 solutions as practical. These included routine screening for dual diagnosis at intake, and a range of proposals for closer intersectoral communication such as exchanging client information, developing shared treatment plans, conducting joint case conferences and offering consultation facilities. Conclusions: A wide range of problems for the management of comorbid disorders were identified. While solution of some problems will require resource allocation, many may be addressed by closer liaison between existing services.