Grant Sara

The global epidemiology and burden of psychostimulant dependence: Findings from the Global Burden of Disease Study 2010

AIMS To estimate the global prevalence of cocaine and amphetamine dependence and the burden of disease attributable to these disorders. METHODS An epidemiological model was developed using DisMod-MR, a Bayesian meta-regression tool, using epidemiological data (prevalence, incidence, remission and mortality) sourced from a multi-stage systematic review of data. Age, sex and region-specific prevalence was estimated for and multiplied by comorbidity-adjusted disability weightings to estimate years of life lost to disability (YLDs) from these disorders. Years of life lost (YLL) were estimated from cross-national vital registry data. Disability-adjusted life years (DALYs) were estimated by summing YLDs and YLLs in 21 regions, by sex and age, in 1990 and 2010. RESULTS In 2010, there were an estimated 24.1 million psychostimulant dependent people: 6.9 million cocaine and 17.2 million amphetamines, equating to a point prevalence of 0.10% (0.09-0.11%) for cocaine, and 0.25% (0.22-0.28%) for amphetamines. There were 37.6 amphetamine dependence DALYs (21.3-59.3) per 100,000 population in 2010 and 15.9 per 100,000 (9.3-25.0) cocaine dependence DALYs. There were clear differences between amphetamines and cocaine in the geographic distribution of crude DALYs. Over half of amphetamine dependence DALYs were in Asian regions (52%), whereas almost half of cocaine dependence DALYs were in the Americas (44%, with 23% in North America High Income). CONCLUSION Dependence upon psychostimulants is a substantial contributor to global disease burden; the contribution of cocaine and amphetamines to this burden varies dramatically by geographic region. There is a need to scale up evidence-based interventions to reduce this burden.

The P300 ERP component: an index of cognitive dysfunction xin depression?

A number of measures of brain function have suggested that depression is associated with cerebral hypoactivity. This study examines the late components of the event-related potential (ERP), in particular the P300 component, in depression. The P300 component is thought to index the updating of neurocognitive models which are concerned with the prediction of future events. Cognitive theories of depression include the proposition that depression may be characterized by abnormalities in the prediction of future events. The P300 component may therefore provide one neurophysiological index of cognitive dysfunction in depression. Twenty-seven subjects (14 medicated, 13 drug-free) fulfilling DSM-III criteria for Major Depression were compared to 27 age- and sex-matched normal controls. The amplitudes and latencies of N100, P200, N200 and P300 ERP components, reaction time and task accuracy were recorded during a standard auditory discrimination task. No significant differences were found in any ERP component measure or in reaction-time between the groups. Depressed subjects performed the experimental task significantly less accurately than normal controls, but this was not reflected in the ERPs.

In the eye of the beholder: Processing body shape information in anorexic and bulimic patients

Previous body image studies have suggested that dieting-disordered patients (anorexia and bulimia nervosa) differ from normal subjects in their estimation of body size and desired body shape. It was hypothesized that overconcern with body shape in these patients would be reflected in their visual analyses of specific parts of their bodies. This hypothesis was investigated using a system that combines an infrared light source, video camera, dedicated microprocessor, and computer to monitor eye-gaze direction at 50 times per second. Fifteen dieting-disordered patients and 10 control subjects were examined in this way while simultaneously being shown a picture of themselves on a TV screen. Preliminary results suggest that the patients tend to focus on those parts of their body with which they are dissatisfied, while normal subjects scan their whole body shape. Objective assessment of areas of specific bodily concern among dieting-disordered patients, as well as the examination of voluntary and involuntary processing of self-referential stimuli, is offered by the use of such technology.

Crystalline methamphetamine use and methamphetamine-related harms in Australia

INTRODUCTION AND AIMS Concerns about crystal methamphetamine use and harm have increased in multiple countries. This paper describes how changes in the availability and use of crystal methamphetamine have impacted on methamphetamine-related harms in Australia. DESIGN AND METHODS Data on methamphetamine use were obtained from population-level surveys, health service data and surveys of drug use among sentinel groups of ecstasy users and people who inject drugs. Data were obtained on seizures, arrests, clandestine laboratory detections, hospital separations, mental health unit admissions, drug telephone helpline calls and drug treatment episodes. Segmented linear regression models were fitted to identify changes in these series using log-transformed data where appropriate. RESULTS The availability of crystal methamphetamine has increased as evidenced by increased laboratory detections, domestic seizures and purity of the seized drug. Population surveys do not report an increase in the number of people who used at least once in the past year. However, more users report using crystal methamphetamine rather than lower-purity powder methamphetamine and more regular use. Indicators of methamphetamine-related harms have increased in parallel with this change. Amphetamine-related helpline calls, drug treatment, arrests and hospital admissions for amphetamine disorders and psychosis all peaked in the mid-2000s, declined for several years and have increased steeply since 2010. DISCUSSION AND CONCLUSIONS The increased availability and use of crystal methamphetamine have been associated with increased regular use and harms. Treatment is required for those experiencing problems and the capacity of health services to provide care needs to be enhanced.[Degenhardt L, Sara G, Connor JP, McKetin R, Roxburgh A, Dobbins T, Farrell M, Burns L, Hall WD. Crystalline methamphetamine use and methamphetamine-related harms in Australia. Drug Alcohol Rev 2017;36:160-170].

Stimulant use disorders in people with psychosis: A meta-analysis of rate and factors affecting variation

Objective: Stimulant abuse and dependence often complicate the care of people with psychotic disorders. This study systematically reviews the prevalence estimates reported for stimulant abuse and dependence in people with psychotic disorders, and examines personal, clinical, regional and methodological factors which explain variation in these rates. Methods: PsychINFO, EMBASE and MEDLINE (1946–2013) were searched systematically for studies reporting on stimulant drug use disorders in representative samples of people with psychotic disorders. Random effects models estimated the pooled rate of a stimulant use disorder, defined to include stimulant abuse and stimulant dependence. Study characteristics associated with heterogeneity in rates of stimulant use disorder were examined by subgroup analyses for categorical variables, by meta-regression for continuous independent variables and by multiple meta-regression. Results: Sixty-four studies provided 68 estimates of lifetime or recent stimulant use disorders in 22,500 people with psychosis. The pooled rate of stimulant use disorder was 8.9% (95% CI 7.4%, 10.5%). Higher rates of stimulant use disorders were reported in studies of affective psychosis, studies from inpatient settings, studies from the USA and Australia, and studies with higher rates of cannabis disorder; in multiple meta-regression analysis these factors explained 68% of between-study variance. Rates of stimulant use disorder were stable over time, and unrelated to age, sex, stage of psychosis, type of stimulant drug or study methodology factors. Conclusions: Reported rates of stimulant use disorder in people with psychosis are much higher than in the general population but vary widely and are associated with regional, service setting and clinical differences between studies. It is likely that stimulants contribute to the overall burden of psychosis, and that social and environmental factors combine with drug and illness-related factors to influence stimulant use in psychosis.

Stimulant and other substance use disorders in schizophrenia: Prevalence, correlates and impacts in a population sample

Objectives: Stimulants may worsen psychotic symptoms but there is limited evidence about the impact of stimulant abuse in people with schizophrenia. This study examined the prevalence and correlates of stimulant and other drug disorders in a population-based sample of people with schizophrenia, examining associations with frequent service use, physical health comorbidities and accommodation instability. Methods: New South Wales (NSW) hospital, community mental health and emergency department data were used to examine health service contact over 5 years in 13,624 people with a diagnosis of schizophrenia. Associations of stimulant disorders were examined with multinomial logistic regression, comparing people with no substance disorders to those with cannabis disorders, stimulant disorders or both. Results: Of people with schizophrenia, 51% had substance disorders, including 14% with stimulant disorders. Stimulant disorders were more common in young adults and in urban areas, less common in migrants, and unrelated to initial social disadvantage. More than 80% of those with stimulant disorders also had cannabis disorders. Service use and harms were most common in this group, including frequent mental health admissions (59%), frequent emergency department presentations (52%), admissions with injury or self-harm (44%), infectious disease diagnoses (22%), multiple changes of residence (61%), movement to more disadvantaged locations (42%) and periods of homelessness (18%). People with stimulant disorders alone had higher rates of self-harm, infectious disease and non-mental health admissions than people with cannabis disorders alone. Conclusions: Stimulant disorders occur in people with schizophrenia and in first-episode psychosis at rates more than 10 times that of the broader population. Stimulant disorders are likely to worsen the burden of psychosis, and strategies are needed to engage and support the highly disadvantaged group of people with schizophrenia who have cannabis and stimulant disorders.

Stimulant use disorders: characteristics and comorbidity in an Australian population sample.

Objective: To describe the correlates of stimulant use disorders (abuse, dependence) in an Australian population sample, to compare the characteristics of stimulant users with and without stimulant use disorders and to describe the patterns of service use and help-seeking in people with stimulant use disorders. Methods: Data were drawn from the 2007 National Survey of Mental Health and Wellbeing, which sampled 8841 residents of private dwellings in Australia in 2007. Lifetime DSM-IV substance use and mental disorder diagnoses were obtained from interviews conducted by lay interviewers, using the Composite International Diagnostic Interview (CIDI). Socio-demographic, socio-economic and clinical correlates of stimulant use disorders were identified using binary logistic regression models. Stimulant users with and without stimulant use disorders were compared to non-stimulant users via multinomial logistic regression models. Results: Compared to Australians without stimulant use disorder, people with stimulant use disorders were younger, more likely to be male, of non-heterosexual orientation and born in Australia, but were not more socially disadvantaged. Lifetime comorbidity rates were high: 79% of persons with stimulant use disorders had a lifetime alcohol use disorder, 73% a lifetime cannabis use disorder, and more than one third a lifetime mood or anxiety disorder. Stimulant use disorders were associated with a family history of substance use, affective disorders and psychosis. One in five people with lifetime stimulant use disorders had been imprisoned, homeless or hospitalised for substance or mental health problems, and 13% reported at least one symptom of psychosis. Nearly half had sought help for substance or mental health problems, primarily from General Practitioners (GPs), psychologists or psychiatrists. Conclusions: Stimulant use disorders in a representative population sample are associated with significant comorbidity and harm. Many persons with stimulant use disorders had sought care and found this helpful. There is scope for screening and intervention in this group.

A brief measure of vocational activity and community participation: development and reliability of the Activity and Participation Questionnaire.

Objectives: Social and economic marginalization are significant problems for many people living with mental illness. Clinicians and policy-makers have increased their focus on these aspects of recovery. Current outcome measures, however, do not support this focus, and detailed functional measures are not suitable for routine clinical use. This report describes the development and test–retest reliability of the Activity and Participation Questionnaire (APQ6); a self-report measure of vocational activity and social participation for routine use in community mental health services. Method: The APQ6 was developed from concepts of the Australian Bureau of Statistics Labour Force Surveys and Census. Field testing and consumer consultation were undertaken in New South Wales (NSW) mental health rehabilitation services. Test–retest reliability trials were conducted simultaneously by research teams in NSW and Queensland. Results: Pairs of short-cycle test–retest reliability interviews were obtained from 129 mental health service consumers. Consumer feedback and test–retest reliability results at question and item levels indicate good construct validity. The measure has utility as both a telephone and a personal interview in community mental health settings. Conclusions: The reported psychometric properties support the proposed use of the APQ6 as a recovery-orientated measure focusing on vocational activity and community participation. The APQ6 is being introduced for routine use by NSW mental health services.

The Impact of Cannabis and Stimulant Disorders on Diagnostic Stability in Psychosis

BACKGROUND Substance abuse adds to diagnostic uncertainty in psychosis and may increase the risk of transition from brief and affective psychoses to schizophrenia. This study examined whether comorbid substance disorder was associated with diagnostic instability and progression from other psychosis diagnoses to schizophrenia and whether effects differed for cannabis and stimulant-related disorders. METHOD We identified 24,306 individuals admitted to hospital with an ICD-10 psychosis diagnosis between 2000 and 2011. We examined agreement between initial diagnosis and final diagnosis over 2-5 years and predictors of diagnostic change toward and away from a final diagnosis of schizophrenia. RESULTS Nearly half (46%) of participants with initial brief, atypical, or drug-induced psychoses were later diagnosed with schizophrenia. Persisting illicit drug disorders did not increase the likelihood of progression to schizophrenia (OR = 0.97; 95% CI, 0.89-1.04) but increased the likelihood of revision of index psychosis diagnosis away from schizophrenia (OR = 1.55; 95% CI, 1.40-1.71). Cannabis disorders predicted an increased likelihood of progression to schizophrenia (OR =1.12; 95% CI, 1.01-1.24), while stimulant disorders predicted a reduced likelihood (OR = 0.81; 95% CI, 0.67-0.97). Stimulant disorders were associated with greater overall diagnostic instability. CONCLUSIONS Many people with initial diagnoses of brief and affective psychoses are later diagnosed with schizophrenia. Cannabis disorders are associated with diagnostic instability and greater likelihood of progression to schizophrenia. By contrast, comorbid stimulant disorders may be associated with better prognosis in psychosis, and it may be important to avoid premature closure on a diagnosis of schizophrenia when stimulant disorders are present.

Meta-analysis of self-reported substance use compared with laboratory substance assay in general adult mental health settings.

An accurate assessment of substance use is necessary to make a correct psychiatric diagnosis and to provide appropriate treatment. This study uses meta‐analysis to establish the strength of the association between self‐reported substance use and the results of laboratory substance assay including the testing for specific substances and screening for any substance use in psychiatric hospitals and in community mental health settings.