Aj Matthews

Alcohol Use and Risk Taking Among Regular Ecstasy Users

We examine alcohol use in conjunction with ecstasy use and risk-taking behaviors among regular ecstasy users in every capital city in Australia. Data on drug use and risks were collected in 2004 from a national sample of 852 regular ecstasy users (persons who had used ecstasy at least monthly in the preceding 6 months). Users were grouped according to their typical alcohol use when using ecstasy: no use, consumption of between one and five standard drinks, and consumption of more than five drinks (“binge” alcohol use). The sample was young, well educated, and mainly working or studying. Approximately two thirds (65%) of the regular ecstasy users reported drinking alcohol when taking ecstasy. Of these, 69% reported usually consuming more than five standard drinks. Those who did not drink alcohol were more disadvantaged, with greater levels of unemployment, less education, higher rates of drug user treatment, and prison history. They were also more likely than those who drank alcohol when using ecstasy to be drug injectors and to be hepatitis C positive. Excluding alcohol, drug use patterns were similar between groups, although the no alcohol group used cannabis and methamphetamine more frequently. Binge drinkers were more likely to report having had three or more sexual partners in the past 6 months and were less likely to report having safe sex with casual partners while under the influence of drugs. Despite some evidence that the no alcohol group were more entrenched drug users, those who typically drank alcohol when taking ecstasy were as likely to report risks and problems associated with their drug use. It appears that regular ecstasy users who binge drink are placing themselves at increased sexual risk when under the influence of drugs. Safe sex messages should address the sexual risk associated with substance use and should be tailored to reducing alcohol consumption, particularly targeting “heavy” alcohol users. The studys limitations are noted.

Can the Severity of Dependence Scale Be Usefully Applied to ‘Ecstasy’?

Background/Aims: Although use of ‘ecstasy’ (drugs sold as containing 3,4-methylenedioxymethamphetamine) is prevalent, it is typically infrequent, and treatment presentations involving ecstasy as a principal problem drug are relatively rare. Human case reports and animal literature suggest dependence potential, although there may be some unique aspects to this syndrome for ecstasy in comparison to other substances. The Severity of Dependence Scale (SDS) was examined to determine whether this could usefully identify ‘dependent’ ecstasy consumers. Methods: We conducted a cross-sectional survey of 1,658 frequent (at least monthly) ecstasy consumers across Australia, assessing drug use, associated harms and risk behaviours. Dependence was evaluated with the SDS, using a cut-off of ≥4 to identify potential ‘dependence’. Results: One fifth of the participants were screened as potentially dependent. These individuals used ecstasy more frequently, in greater amounts, engaged more extensively in risk behaviours and reported greater role interference than other participants. These findings were independent of methamphetamine use or dependence. The underlying structure of the ecstasy SDS was bifactorial. Conclusions: The SDS has demonstrated construct validity as a screening tool to identify ecstasy users at elevated risk of experiencing adverse consequences, including features of dependence. The underlying structure of dependence symptoms differs for ecstasy compared to other drug classes, and some dependent consumers use the drug infrequently. The unique neurotoxic potential and entactogenic effects of ecstasy may require a distinct nosological classification for the experience of dependence associated with the drug.

Factors associated with driving under the influence of alcohol and drugs among an Australian sample of regular ecstasy users

The aim of the present study was to investigate factors associated with driving under the influence (DUI) of alcohol and other drugs (ecstasy, cannabis and methamphetamine) among a group of regular ecstasy users. Participants were those who participated in the Australian Ecstasy and related Drug Reporting System (EDRS) in 2007 and had recently driven a motor vehicle (n=573). Participants were administered a semi-structured face-to-face interview which included questions about ecstasy and other drug use, associated health-related issues, and risk behaviours. Close to half of those who were current consumers of ecstasy, cannabis, and methamphetamine had recently driven under the influence of these drugs, while two-fifths of current alcohol users reported recent drink driving. Frequency of use for each substance was the most significant correlate of DUI of alcohol, cannabis, and methamphetamine, suggesting that interventions targeting high frequency and problematic drug use may be useful in reducing the occurrence of DUI for these substances. Low perception of the likelihood of having an accident was the most significant correlate of DUI of ecstasy and also related significantly to DUI of other substances. Perceptions of low likelihood of being apprehended by police and demographic characteristics such as younger age and male sex were also weakly associated with DUI. Together these findings have important implications for targeted interventions aimed at reducing the occurrence of DUI among regular drug users.

The rise of new psychoactive substance use in Australia.

New Psychoactive Substances are now a feature of Australias recreational drug market. Little is known, however, about the prevalence of use, the characteristics of people who use them and the relationship between the NPS and ecstasy markets. This study examined the prevalence and correlates of NPS use amongst a group of regular ecstasy users in Australia. Participants were recruited if they had used ecstasy at least six times in the previous six months, lived in a capital city and were over 16 years of age. Purposive sampling was used, recruiting through universities and colleges, word of mouth and street press. 654 participants were recruited in 2013. Respondents who had used an NPS in the past six months were compared to those who had not. NPS were used by 44% of the total sample. In 2013 2C-I (14%) and 2C-B (8%) were the most prevalent NPS. Respondents in the NPS group were younger and reported more frequent use of more types of drugs. They were also more likely to rate the purity of ecstasy as low relative to those in the no NPS group. NPS are now an established part of Australias recreational drug scene and NPS with hallucinogenic effects are now used most commonly. Monitoring systems need to develop capacity to monitor this highly dynamic market.

Neural correlates of performance trade-offs and dual-task interference in bimanual coordination: an ERP investigation.

Previous behavioural studies have provided a framework for understanding coordination dynamics using traditional dual-task methodology. The central cost associated with stabilising bimanual coordination patterns has been inferred from performance trade-offs during the concurrent performance of a probe reaction time (RT) task. The present study aimed to provide a direct measure of central cost by assessing electrophysiological correlates of performance trade-offs under dual-task conditions. Event-related potentials (ERPs) were recorded from 16 participants while an anti-phase bimanual coordination task and a visual three-stimulus task were performed under single task conditions and under dual-task conditions in which either task was prioritised. The visual task required a foot response to low probability target stimuli, while low probability distracter and high probability standard stimuli were ignored. Consistent with previous research, there was a performance trade-off between pattern stability and RT to visual targets when the coordination task was prioritised relative to when the visual task was prioritised. This was accompanied by a significant reduction in central P3a amplitude elicited by distracter stimuli and parietal P3b amplitude elicited by target stimuli. These findings indicate that prioritisation and thus stabilisation of the motor task reduced the amount of central/perceptual and automatic attentional resources available to perform the visual task providing insight into CNS mechanisms that constrain the coordination of movement through the allocation of attentional resources.

Drug detection dogs in Australia: more bark than bite?

INTRODUCTION AND AIMS Canines are often used by police for drug detection and deterrence. However, their effectiveness has been questioned. This paper aims to describe the experience of regular illicit drug users when in contact with drug detection dogs. DESIGN AND METHODS Regular ecstasy users (n = 2127) were interviewed across Australia between 2008 and 2010 as part of the Ecstasy and Related Drugs Reporting System. RESULTS Over the 3 year period, there was increased visibility of drug detection dogs by regular ecstasy users. New South Wales was the jurisdiction with the most reported sightings, mainly occurring at festivals or live music events. Despite this police presence, however, detection and deterrence rates remained low. Approximately two-thirds of participants who had seen the drug detection dogs had drugs in their possession at the most recent sighting, yet less than 7% were positively identified by dogs. Further, the majority of participants in possession of drugs took no actions after sighting the dogs, whereas a small group hastily consumed the drugs. DISCUSSION AND CONCLUSIONS The low proportion of reported positive notifications from the dogs by the participants who had drugs on them at the time of sighting questions the accuracy and effectiveness of this procedure. Despite the increased visibility of police drug detection dogs, regular ecstasy users continue to use and be in possession of illicit drugs in public, suggesting a limited deterrence effect. The hasty consumption of drugs upon sighting the dogs also raises health concerns.

The effects of single-dose lorazepam on memory and behavioural learning.

To assess the influence of lorazepam on memory and behavioural learning, a non-clinical sample of undergraduate psychology students (n= 24), received lorazepam (2.5 mg) or placebo orally. Pre-drug and post-drug neuropsychological assessment comprised the Rey auditory verbal learning test, verbal fluency test, digit span and word stem completion. Relative to placebo, lorazepam induced a marked deficit in delayed free-recall, perceptual priming, and written word fluency, with preservation of digit span. Behavioural learning was assessed on a computer-aided vicarious exposure treatment for obsessive–compulsive disorder, administered post-drug, and repeated 1 week later, drug free. Compared to placebo, lorazepam treated participants enacted 51% less exposure activity on the behavioural learning task post-drug. Whilst both groups enacted increased exposure at the drug-free session, exposure activity was 49% less in the lorazepam group, indicating a carryover effect of the impaired learning under drug 1 week before. There were no significant differences between lorazepam and placebo on indices of overall activity on the program. These results suggest lorazepam-induced impairment in the ability to learn behavioural strategies, possibly due to impaired acquisition of information into long-term episodic memory. These findings suggest caution in the co-prescribing of benzodiazepines in people undergoing behavioural therapies in clinical populations.

Verbal Learning and Memory in Cannabis and Alcohol Users: An Event-Related Potential Investigation

Aims: Long-term heavy use of cannabis and alcohol are known to be associated with memory impairments. In this study, we used event-related potentials to examine verbal learning and memory processing in a commonly used behavioral task. Method: We conducted two studies: first, a small pilot study of adolescent males, comprising 13 Drug-Naive Controls (DNC), 12 heavy drinkers (HD) and 8 cannabis users (CU). Second, a larger study of young adults, comprising 45 DNC (20 female), 39 HD (16 female), and 20 CU (9 female). In both studies, participants completed a modified verbal learning task (the Rey Auditory Verbal Learning Test, RAVLT) while brain electrical activity was recorded. ERPs were calculated for words which were subsequently remembered vs. those which were not remembered, and for presentations of learnt words, previously seen words, and new words in a subsequent recognition test. Pre-planned principal components analyses (PCA) were used to quantify the ERP components in these recall and recognition phases separately for each study. Results: Memory performance overall was slightly lower than published norms using the standardized RAVLT delivery, but was generally similar and showed the expected changes over trials. Few differences in performance were observed between groups; a notable exception was markedly poorer delayed recall in HD relative to DNC (Study 2). PCA identified components expected from prior research using other memory tasks. At encoding, there were no between-group differences in the usual P2 recall effect (larger for recalled than not-recalled words). However, alcohol-related differences were observed in a larger P540 (indexing recollection) in HD than DNC, and cannabis-related differences were observed in a smaller N340 (indexing familiarity) and a lack of previously seen > new words effect for P540 in Study 2. Conclusions: This study is the first examination of ERPs in the RAVLT in healthy control participants, as well as substance-using individuals, and represents an important advance in methodology. The results indicate alterations in recognition memory processing, which even if not manifesting in overt behavioral impairment, underline the potential for brain dysfunction with early exposure to alcohol and cannabis.

Is khat use disorder a valid diagnostic entity

AIMS This study aimed to validate the presence of a khat use disorder syndrome using DSM-5 criteria and to examine its relationship with increased experience of harms. DESIGN Cross-sectional, purposive sample of current khat-chewers, recruited from khat markets and cafes. SETTING Participants were recruited from the general community and from Adama Science and Technology University in Ethiopia. PARTICIPANTS A total of 400 current khat consumers aged 16 and above were recruited between September 2014 and January 2015 MEASURES: Survey comprising current clinical symptoms (using a modified Alcohol Use Disorder and Associated Disabilities Interview Schedule-IV), and validated measures of health, psychological distress, quality of life and academic functioning. FINDINGS A third [35.5% 95% confidence interval (CI) = 31.0-40.3] of respondents reported daily khat use and a quarter (25.4% 95% CI = 21.4-30.0) using three times or more per week. Using DSM-5 criteria, 10.5% (95% CI = 7.9-13.9) were categorized as experiencing mild, 8.8% (95% CI = 6.4-12.0) moderate and 54.5% (95% CI = 49.6-59.3) severe khat use disorder. Confirmatory factor analysis demonstrated a good fit of symptoms to a single underlying construct, consistent with other substance use disorders. Individuals categorized as experiencing khat use disorder demonstrated significantly greater frequency [odds ratio (OR) = 45.29; 95% CI = 10.97-19.01) and quantity of khat use (OR = 2.35; 95% CI = 1.29-4.29). They also demonstrated increased financial problems associated with use, greater problems with academic functioning and higher rates of self-reported mental health problems, higher psychological distress and poorer quality of life. Treatment access was poor, with only one-third (32.9%) of individuals with khat use disorder reporting life-time access, near-exclusively related to help-seeking from friends and relatives. CONCLUSION The construct of a substance use disorder syndrome for khat using DSM-5 criteria appears valid and performs in a manner consistent with other substances of dependence. Individuals with khat use disorder experience substantial problems in association with khat use. Despite this, there are low levels of help-seeking for these problems.

An Investigation of Factors Associated with Depressive Symptoms among a Sample of Regular Ecstasy Consumers

Aims/Objectives: Methylenedioxymethamphetamine affects the central serotonergic system, and there is some evidence for an association between ecstasy use (drugs sold as methylenedioxymethamphetamine) and depression. The aim of the present study was to investigate the incidence of self-reported depression and associated help-seeking among a sample of regular ecstasy users. A further aim was to examine the correlates of depressive symptomatology in this population. Materials and Methods: 100 regular ecstasy consumers (at least monthly use) were interviewed as part of the Ecstasy and Related Drug Reporting System in Tasmania, Australia. Participants were also administered epidemiological measures of depression (Center for Epidemiological Studies Depression Scale) and psychological distress (Kessler Psychological Distress Scale). Results: One quarter (23%) of participants self-reported recent experience of depression, a rate notably greater than the general population. However, only one third of these participants had attended a health professional for this issue. A range of drug use factors (e.g. frequency and quantity of ecstasy use, frequent cannabis or methamphetamine use, intravenous drug use, polydrug use, binge drug use, harmful alcohol use, and elevated psychological dependence scores for ecstasy and methamphetamine) were associated with high levels of depressive symptomatology. Conclusion: These findings are consistent with an association between depressive symptomatology and ecstasy and other drug use. Harm reduction strategies which target drug use factors such as those identified in this study may also aid in the reduction of the experience of depression. Considering the low levels of help-seeking among this population, improving awareness and access to information and treatment for depression may also be important.