Concurrent and simultaneous polydrug use: latent class analysis of an Australian nationally representative sample of young adults

Situational assessment and epidemiology of HIV, HBV and HCV among people who use and inject drugs in Ghana

INTRODUCTION

People who inject drugs (PWID) and people who use drugs (PWUD) are an important population group that remain under-served in Ghana. Though PWID and PWUD are among the key populations most-at-risk to acquire sexually transmitted or blood-borne diseases, they are among those with the least access to human immunodeficiency (HIV), hepatitis B (HBV) and hepatitis C (HCV) viruses' prevention, care and treatment services in Ghana due to lack of data on them. We provide a rapid assessment of the PWUD and PWID situation in Ghana.

METHODS

This rapid cross-sectional design undertook consultative meetings between the study team and relevant stakeholders, including Civil Society Organizations (CSO) working with PWUD/PWID. The assessment considered a representative sample of PWID and PWUD. It was conducted in four (4) selected regions of Ghana (Greater Accra, Ashanti, Western, and Northern). Overall, 323 participants were interviewed using respondent-driven sampling (RDS) approach. Information obtained from participants were demographics, HIV risk behaviors, human immunodeficiency (HIV) and sexually transmitted infections (STI)-related knowledge HIV/HCV/HBV screening, attitude, and practices among others. Analyses were conducted using Stata version 17 and RDSAT version 7.1.46 software.

FINDINGS

Drug use was found to be more prevalent among the youth with a median age of 37 years. Majority of the respondents were males (86%). About 28% of the female respondents identified themselves as sex workers, while about 74% have been involved in transactional sex. The median age at which respondents started using and injecting drugs was 20 and 22 years respectively. Majority (68%) of the respondents consume drugs through smoking, with 20% through snorting, inhaling or swallowing and 12% through injection. The drug mostly used among the respondents was heroin (52%). The most commonly injected drug was cocaine (55%). About 64.7% of respondents reported mixing two or more drugs. HIV prevalence among respondents was 2.5%, 12.3% among women and 17.7% among women engaged in sex work, highlighting the overlap vulnerability. The prevalence of hepatitis C was 6.0%, and Hepatitis B was 4.5%. Access to care is limited, with 63% of the respondents never been tested for HIV.

CONCLUSION

These rapid assessment findings reveal the challenging conditions for people who use and inject drugs coupled with a relatively high prevalence of HIV and Hepatitis C compared to the general population. However, it also reveals that Ghana has a window of opportunity to prevent an exponential spread of HIV and Hepatitis in this population. Therefore, there is the need to implement prevention and treatment programs for HIV and hepatitis among people who use and inject drugs including essential strategies for an enabling environment in Ghana.

Simultaneous Substance Use With Alcohol in a Community-Based Sample of Young Adults

Objective: Simultaneous substance use is associated with worse outcomes than concurrent use. Further investigations into simultaneous use are warranted because there is limited knowledge about the co-use of substances other than alcohol and cannabis. Study aims were to examine: (1) the prevalence of simultaneous use of substances with alcohol, (2) the extent to which use patterns are related to key correlates (i.e., psychological functioning, sensation seeking), and (3) differences by college status. Methods: Participants were 623 young adult drinkers who were recruited online to complete a one-time survey. Results: Cannabis (54.3%), tobacco (53.7%), and stimulants (46.5%) were most frequently used with alcohol. Moderation analyses showed the positive association between simultaneous use and psychological distress was stronger for students whereas the positive association with sensation seeking was stronger for nonstudents. Conclusions: Results highlight the need for future research and intervention efforts that consider the link between simultaneous use and psychological wellbeing while acknowledging that educational attainment may differentially influence these factors.

A latent class analysis of mental disorders, substance use, and aggressive antisocial behavior among Swedish forensic psychiatric patients

BACKGROUND

Patients in the forensic mental health services (FMHS) with a mental disorder, a co-occurring substance use disorder (SUD), and high risk of aggressive antisocial behavior (AAB) are sometimes referred to as the 'triply troubled'. They suffer poor treatment outcomes, high rates of criminal recidivism, and increased risk of drug related mortality. To improve treatment for this heterogeneous patient group, more insight is needed concerning their co-occurring mental disorders, types of substances used, and the consequent risk of AAB.

METHODS

A three-step latent class analysis (LCA) was used to identify clinically relevant subgroups in a sample of patients (n = 98) from a high-security FMHS clinic in Sweden based on patterns in their history of mental disorders, SUD, types of substances used, and AAB.

RESULTS

A four-class model best fit our data: class 1 (42%) had a high probability of SUD, psychosis, and having used all substances; class 2 (26%) had a high probability of psychosis and cannabis use; class 3 (22%) had a high probability of autism and no substance use; and class 4 (10%) had a high probability of personality disorders and having used all substances. Both polysubstance classes (1 and 4) had a significantly more extensive history of AAB compared to classes 2 and 3. Class 3 and class 4 had extensive histories of self-directed aggression.

CONCLUSIONS

The present study helps disentangle the heterogeneity of the 'triply troubled' patient group in FMHS. The results provide an illustration of a more person-oriented perspective on patient comorbidity and types of substances used which could benefit clinical assessment, treatment planning, and risk-management among patients in forensic psychiatric care.

Understanding the complexity, patterns, and correlates of alcohol and other substance use among young people seeking help for mental ill-health

PURPOSE

Use of alcohol and other substances is a multifaceted issue impacting young people across multiple life domains. This paper aims to elucidate patterns of substance use and associated demographic and clinical factors among young people seeking treatment for their mental health.

METHODS

Young people (12-25 years old) were recruited from five youth-specific primary mental health ("headspace") services in Australia. Self-reported substance use and harms in the past 3 months were measured using WHO-ASSIST. Network analyses were conducted to evaluate interrelationships between use and harms associated with different substances. Subgroups were then identified based on whether participants reported using high centrality substances, and associated demographic and clinical factors were assessed with multinomial logistic regression.

RESULTS

1107 youth participated. 70% reported use of at least one substance in the past 3 months, with around 30% of those reporting related health, social, legal or financial problems. Network analysis highlighted substantial interconnections between use and harm indicators for all substances, with amphetamine-type stimulants (ATS) and cannabis being high central substances. Higher levels of substance use and harms were reported in subgroups with ATS or cannabis use and different risk factors were associated with these subgroups.

CONCLUSIONS

Findings highlight the importance of screening for substance use in youth primary mental healthcare settings, offering a key opportunity for early intervention. Clinicians should be aware of the inner connections of use and harms of different drugs and the role of cannabis and amphetamine use as a marker for more substance use profiles.

Multiple Substance Use Patterns and Its Relationship with Imprisonment in a High-Risk Group of Iranian Adults

BACKGROUND

Substance use is recognized as an important factor associated with many diseases and premature deaths and the main risk factor for disability worldwide. This study aims to identify subgroups of substance use in adults and detect the effect of imprisonment on the membership of participants in latent classes of substance use. Study Design: A cross-sectional study.

METHODS

This study was performed on 930 adult people who were referred to behavioral health counseling centers in Tehran province. All participants completed some checklists and questionnaires. Data analysis was performed using chi-square, Fisher's exact test, and latent class analysis (LCA).

RESULTS

Four latent classes were identified, including non-users (58%), cigarette smokers (11.6%), users of low stigma substances (27.4%), and drug users (3.1%). After adjusting for other studied variables, having a history of imprisonment increased the odds of membership in the cigarette smoker class (Odds ratio [OR]=5.82, 95%, confidence interval [CI]: 3.19-10.63) and drug user class (OR=53.59, 95% CI: 18.00- 159.52) compared to non-user class. Among all participants, 84 (9.0%) had a history of imprisonment.

CONCLUSION

Results from the present study indicate that 30.5% of the participants fell under the user of the low-stigma substance or drug user group. Focusing on increasing prisoner's knowledge of the dangers of using different substances and considering various programs for prisoners' leisure time may help reduce substance use prevalence.

Performance on Cognitive Screening Tests and Long-Term Substance Use Outcomes in Patients with Polysubstance Use Disorder

INTRODUCTION

Cognitive impairments among patients with substance use disorders are prevalent and associated with adverse treatment outcomes. However, knowledge of the predictive value of broad cognitive screening instruments on long-term treatment outcomes is limited. The present study aimed to examine the predictive value of measures from the Montreal Cognitive Assessment® (MoCA®), Wechsler Abbreviated Scale of Intelligence (WASI), and the Behaviour Rating Inventory of Executive Function - Adult version (BRIEF-A) on self-reported long-term substance use and abstinence in patients with polysubstance use disorders (pSUD).

METHODS

A cohort (N = 164) of patients with pSUD who started a new treatment sequence in the Stavanger University Hospital catchment area were recruited and followed prospectively for 5 years. Participants completed neurocognitive testing with the MoCA®, WASI, and BRIEF-A at inclusion and were categorized as cognitively impaired or non-impaired according to recommended cut-off values. The sum score of the items from the Drug Use Disorders Identification Test Consumption scale (DUDIT-C) was used as a measure of substance use outcome 1 and 5 years after inclusion. We defined substance abstinence (DUDIT-C = 0) and heavy substance use (DUDIT-C ≥7) to determine whether cognitive impairments measured by the respective instruments were associated with and could predict abstinence and heavy substance use 1 and 5 years after baseline.

RESULTS

At the 1-year follow-up, 54% of the total sample reported total abstinence from substances. Conversely, 31% presented heavy substance use. At 5 years, 64% of the total sample reported abstinence from substances, while 25% presented heavy substance use. The results showed a statistically significant association between cognitive impairment defined from MoCA® and higher continuous scores on DUDIT-C at 1-year follow-up. There were no differences in substance abstinence or heavy substance use between patients with and without cognitive impairment at the 1- and 5-year follow-ups. Furthermore, cognitive impairment did not explain substance abstinence or heavy substance use at the 1- and 5-year follow-ups.

CONCLUSION

Generally, individuals with pSUD may be burdened and lack psychosocial resources to such an extent that cognitive functioning plays a subordinate role in long-term recovery. The present study suggests that results on screening tools assessing broad cognitive domains at treatment initiation have limited clinical value in predicting long-term substance use outcomes. There is a need to establish clinically viable instruments to assess cognitive functions with well-established clinical and ecological validity in the SUD population.

Psychiatric Symptomatology is Associated with Polydrug Use and School Violence in Early Adolescence

This study investigated the association between psychiatric symptoms and polydrug use, school violence, and sociodemographic factors among Brazilian early adolescents. Using the baseline data collection from the effectiveness evaluation of PROERD, a school-based drug use prevention program, implemented in 30 public schools in São Paulo (n = 2316, M age = 12.3 years, 48.5% girls), multinomial logistic regressions were performed using Strengths and Difficulties Questionnaire (SDQ) subscales as response variables, and polydrug use, school violence, and sociodemographic characteristics as explanatory variables. In most SDQ subscales, girls and older students were more likely to have psychiatric symptoms. A positive association was identified between polydrug use and psychiatric symptoms. It was found that those who suffered and perpetrated physical violence had a greater likelihood of presenting psychiatric symptoms. Preventive interventions should consider the greater vulnerability related to the mental health of girls, older students, and those who suffer and perpetrate physical violence at school.

Polysubstance Use Patterns among Outpatients Undergoing Substance Use Disorder Treatment: A Latent Class Analysis

Substance Use Disorders (SUDs) pose significant challenges to both individuals and society at large. The primary focus of existing research with clinical SUD populations has been on individual substances, but research is required to better understand the profiles of individuals who use different substances simultaneously. The purpose of the current study was, therefore, to identify patterns of use among subjects (n = 1025) who reported using multiple substances by adopting a Latent Class Analysis (LCA) methodology. The Addiction Severity Index (ASI-lite) was included as a measure of substance misuse, we performed LCA to identify patterns of substance use through the administration of the ASI-Lite. Responses were collected from the following substances: alcohol, cannabis/cannabinoids, opioids and heroin, and cocaine. Results identified two latent classes: (1) alcohol use dominant, and (2) poly-abuser use dominants. Class 1 represented 60.0% of the sample and refers to individuals with the dominant use of alcohol, of those a higher proportion (47%) reported low-frequency use (1 to 7 days per month) and 26% reported a frequency of use of 24 to 30 days per month. Furthermore, 18% used alcohol in combination with cocaine. Class 2 represents 40.0% of the sample. This class is characterized by low-frequency and high-frequency users of several substances. The results obtained highlight the importance of deepening the study of the concomitant use of substances in individuals with SUDs to better understand the health risk of the combined use of two or more substances.

Polydrug Definition and Assessment: The State of the Art

Polydrug use is a very common phenomenon and represents an important public health problem. The definition of the term has varied since its inception, and consequently so have forms of self-report evaluation. The aim of this review is to offer an overview of how the concept has evolved and its forms of evaluation through self-reporting. A search of the term polydrug was conducted on the PubMed portal up to August 2022, with a total of 2076 publications detected containing the word polydrug in their title, abstract or keywords. This includes publications that represent an advance in the definition and assessment of this construct through self-reports, which may be useful for researchers carrying out future studies in the field. The importance of distinguishing between concurrent and simultaneous polydrug use and the need to employ comparable measures in parameters for the frequency, magnitude and combination of psychoactive substances involved in polydrug use are two of the main recommendations emerging from this review.

College students mandated to substance use courses: Age-of-onset as a predictor of contemporary polysubstance use

Objective: College campuses report alcohol and other drug policy violations as the most frequent reason students receive disciplinary referrals and, thus, are mandated to programming. This study sought to determine predictors of mandated students' alcohol use frequency, and the likelihood of early-onset alcohol using college students enrolled in mandated programming engaging in current polysubstance use. Methods and participants: Employing a purposive sampling method, n = 822 participants were recruited from a pool of students who violated their university's alcohol policy between October 2019 and July 2021. Results: Data analysis revealed early-onset alcohol use (p < .001), gender ID (p < .01), Greek Affiliation (p < .001), ethnicity (p < .05), and perceived norms (p < .001) significantly predicted alcohol frequency. Analysis also revealed engaging in early-onset alcohol use significantly predicted current participation in polysubstance use (p < 0.01), outside of controls. Conclusions: University programs should consider exploring polysubstance use targeted interventions to mitigate these harmful behaviors and associated negative consequences.

Examining the heterogeneity of polysubstance use patterns in young adulthood by age and college attendance

Substance use in young adulthood and polysubstance users (PSU), in particular, pose unique risks for adverse consequences. Prior research on young adult PSU has identified multiple classes of users, but most work has focused on college students. We examined PSU patterns by age and college attendance during young adulthood in two nationally representative samples. Using National Epidemiological Survey on Alcohol and Related Conditions (NESARC) Wave 1 and NESARC-III data sets, multigroup latent class analysis (MG-LCA) was employed to examine PSU patterns based on age (18-24 vs. 25-34) and determine whether solutions were similar (i.e., statistically invariant) by college attendance/graduation. Classes were estimated by binary past-year use of sedatives, tranquilizers, opioids/painkillers, heroin, amphetamines/stimulants, cocaine, hallucinogens, club drugs, and inhalants, and past-year frequency of alcohol, cigarette, and cannabis use. PSU patterns are largely replicated across waves. Model fit supported 3-class solutions in each MG-LCA: Low frequency-limited-range PSU (alcohol, cigarettes, and cannabis only), medium-to-high frequency limited-range PSU (alcohol, cigarettes, and cannabis only), and extended-range PSU (ER PSU; all substances). Apart from one model, MG-LCA solutions were not invariant by college attendance/graduation, suggesting important differences between these groups. Except for alcohol, cannabis, and cigarette use frequency, results showed that probabilities of illicit and prescription drug use declined in the older age group. Findings also supported examining college and noncollege youth separately when studying PSU. ER PSU may be uniquely vulnerable to coingesting substances, particularly for nongraduates, warranting future research to classify patterns of simultaneous PSU and identify predictors and consequences of high-risk combinations (e.g., alcohol and opioids). (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Test-retest reliability of a new assessment to detect detailed temporal patterns of polysubstance use

OBJECTIVE

While polysubstance use is highly prevalent among people who use drugs, the field lacks a reliable assessment that can detect detailed temporal patterns of polysubstance use. This study assessed the test-retest reliability of the newly developed Polysubstance Use-Temporal Patterns Section (PSU-TPS).

METHODS

Participants who used cocaine plus alcohol and/or marijuana at least once in the past 30 days (n = 48) were interviewed at baseline and approximately 7 days later (retest) using the Substance Abuse Module and the PSU-TPS. Reliability of PSU-TPS measures of quantity, frequency, and duration of polysubstance use was examined using intra-class correlation coefficients (ICCs) and kappa tests.

RESULTS

Excellent reliability was observed for frequencies of concurrent polysubstance use patterns in the past 30 days (ICC range: 0.90-0.94) and quantity of alcohol use (ICC = 0.83), and fair to good reliability was observed for duration of substance use (ICC range: 0.52-0.73).

CONCLUSION

Detailed information regarding cocaine, alcohol, and marijuana polysubstance use in the past 30 days can be reliably measured with the PSU-TPS. Data on the order and timing of polysubstance use at the hourly level will improve our understanding of the implications of sequential and simultaneous use patterns, which can help inform treatment and prevention efforts.

Alterations in white matter microstructure in alcohol and alcohol‐polydrug dependence: Associations with lifetime alcohol and nicotine exposure

Evidence suggests that alcohol dependence (AD) is associated with microstructural deficits in white matter, but the relationship with lifetime alcohol exposure and the impact of polydrug dependence is not well understood. Using diffusion tensor magnetic resonance (MR) imaging, we examined white matter microstructure in relation to alcohol and polydrug dependence using data from the Imperial College Cambridge Manchester (ICCAM) platform study. Tract‐based spatial statistics were used to examine fractional anisotropy (FA) in a cohort of abstinent AD participants, most of whom had a lifetime history of dependence to nicotine. A further subgroup also had a lifetime history of dependence to cocaine and/or opiates. Individuals with AD had lower FA throughout the corpus callosum, and negative associations with alcohol and nicotine exposure were found. A group‐by‐age interaction effect was found showing greater reductions with age in the alcohol‐dependent group within corpus callosum, overlapping with the group difference. We found no evidence of recovery with abstinence. A comparison of alcohol‐only‐ and alcohol‐polydrug‐dependent groups found no differences in FA. Overall, our findings show that AD is associated with lower FA and suggest that these alterations are primarily driven by lifetime alcohol consumption and cigarette smoking, showing no relationship with exposure to other substances such as cocaine, opiates or cannabis. Reductions in FA across the adult lifespan are more pronounced in AD and offer further support for the notion of accelerated ageing in relation to alcohol dependence. These findings highlight there may be lasting structural differences in white matter in alcohol dependence, despite continued abstinence.

Prevalence and sociodemographic factors associated with polysubstance use: analysis of a population-based survey in Jamaica

BACKGROUND

In Latin America and the Caribbean, there is a dearth of research exploring polysubstance use. This study aims to determine the prevalence, varying combinations and associated sociodemographic characteristics of polysubstance use in Jamaica.

METHODS

This study involved a secondary data analysis of the Jamaica National Drug Prevalence Survey 2016 dataset where 4,623 participants between the age of 12 and 65 years from each household were randomly selected as respondents. Statistical analysis was performed to determine the prevalence and the sociodemographic correlates of polysubstance use among Jamaicans.

RESULTS

19.6% of respondents used two or more drugs in their lifetime. Of this amount 68.7% reported past year use and 61.9% reported past month use. Bivariate analyses reported polysubstance use was statistically significantly higher amongst males (U = 54,579, p = 0.000), those living in rural areas (U = 91,892, p = 0.003), non-Christian (U = 89,514, p = 0.014), and married persons (U = 74,672, p = 0.000). Past month polysubstance use was statistically significantly higher among employed persons than unemployed persons were (U = 81,342, p = 0.001). Surprisingly, there was a lack of significant differences between education level, household income and past month concurrent polysubstance use (p = 0.609; p = 0.115 respectively). Logistic regression model indicated males were 3.076 times more likely than females to report past month polysubstance use than females. Also, when compared to those 55-65 years old, participants 35-54 years were 2.922 times more likely and those 18-34 years were 4.914 times more likely to report past month polysubstance use. Additionally, those living in rural areas were 1.508 times more likely than participants living in urban areas to report past month polysubstance use. As it relates to occupational status, when compared to armed forces, skilled workers were 4.328 times more likely and unskilled workers were 7.146 times more likely to report past month polysubstance use.

CONCLUSIONS

One in five Jamaicans identified as polysubstance users, predominated by marijuana as the most common factor amongst the polysubstance combinations examined, signalling the need for early marijuana interventions.

A Scientometric Visualization Analysis for Molecular Mechanisms of Substance Abuse and Its Neurotoxicity From 1997 to 2021

Substance abuse has become a global problem due to drug-induced addiction and neurotoxicity, which causes a huge physical, social, and financial burden. Various kinds of drugs can hijack the users’/abusers’ behavior and associated neurocircuitry. To summarize recent scientific advances on drug abuse, we reviewed relevant publications to analyze research progress and such trends through bibliometric ways. Based on retrieval strategies, a total of 681 scientific records published from 1997 to 2021 were screened and included in the Web of Science (WoS) database. Further scientometric analysis revealed that annual publication output increased across this period, with the United States of America (USA) contributing a significant number of reasons. Research has focused on neurotransmitter, oxidative stress, mitochondrial system injury, and other neurotoxic mechanisms. Neuroimmune, neurotoxic targets, and new psychoactive substances have been hot topics in recent years, which deserve continued research in the future. Specific research on molecular mechanisms has progressed across this period, with an emphasis on the root cause of toxicity and molecular targets for therapy. Moreover, collaborations of international multi-disciplinary research teams have been efficient and need to be encouraged for addiction research and the development of appropriate therapeutic processes.

Polysubstance Use in Early Adulthood: Patterns and Developmental Precursors in an Urban Cohort

Polysubstance use (i.e., simultaneous or sequential use of different psychoactive substances) is associated with increases in the risk of severe health problems and social impairments. The present study leverages community-representative, long-term longitudinal data from an urban cohort to assess: (a) the prevalence and continuation of polysubstance use between adolescence and early adulthood; (b) different patterns of polysubstance use (i.e., combinations of substances) in early adulthood; and (c) childhood risk factors for polysubstance use in early adulthood. At age 20 (n = 1,180), respondents provided comprehensive self-reported information on past-year substance use, including use of legal and illicit substances (e.g., cannabinoids, stimulants, and hallucinogens), and nonmedical use of prescription drugs (e.g., opioids, tranquilizers). In adolescence (ages 13-17), limited versions of this questionnaire were administered. In childhood (ages 7-11), potential risk factors, including individual-level factors (e.g., sensation-seeking, low self-control, aggression, and internalizing symptoms) and social-environmental factors (e.g., social stressors, exposure to others' substance use), were assessed. We fitted latent class models to identify classes of participants with different substance use profiles in early adulthood. The results show that polysubstance use increased between early adolescence and early adulthood. The continuation of polysubstance use was common (stability between all adjacent assessments: odds ratio >7). At age 20, more than one-third of participants reported polysubstance use (involving illicit substances, nonmedical use of prescription drugs, and cannabidiol). Four latent classes with polysubstance use were identified: (1) broad spectrum of substances; (2) cannabis and club drugs; (3) cannabis and the nonmedical use of prescription drugs; and (4) different cannabinoids. Risk factors for any polysubstance use included childhood sensation-seeking and exposure to others' substance use; some childhood risk factors were differentially associated with the four classes (e.g., low self-control in childhood was associated with an increased likelihood of being in the broad spectrum class). The classes also differed with regard to socio-demographic factors. This study revealed that polysubstance use is a widespread and multifaceted phenomenon that typically emerges during adolescence. To facilitate the design of tailored prevention mechanisms, the heterogeneity of polysubstance use and respective socio-demographic and developmental precursors need to be considered.

Trends in binge drinking, marijuana use, illicit drug use, and polysubstance use by sexual identity in the United States (2006-2017)

Background: National studies often examine associations between sexual identity and substance use at a single point in time and neglect to examine whether these associations change over time. The present study examines U.S. trends in the past-year prevalence of binge drinking, marijuana use, illicit drug use, and polysubstance use across sexual identity subgroups (gay, lesbian, bisexual and heterosexual). Methods: The data come from four independent, cross-sectional samples measured by the National Survey of Family Growth (2006-2010, 2011-2013, 2013-2015, and 2015-2017). Based on the consistency in the sampling procedures used over time, merging the four data sets was possible. The target population is men and women 15-44 years of age. Results: Lesbian women had the sharpest decline in past-year binge drinking over time, followed by heterosexual women. The prevalence of binge drinking for bisexual women did not change significantly over time and was higher in 2015-2017 than for any sexual identity subgroup. In contrast, there were no significant differences in the prevalence of binge drinking among men by sexual identity subgroup. Past-year abstinence from substance use was consistently lower among lesbian women, gay men, and bisexual women relative to other sexual identity subgroups. Polysubstance use was consistently more prevalent among bisexual women (e.g., 32.3% in 2015-2017) as compared to other sexual identity subgroups. Conclusion: This is the first study to examine U.S. national trends in alcohol, marijuana, illicit drug, and polysubstance use across sexual identity subgroups, and demonstrates that sexual identity subgroup differences were robust with relatively few changes in trends over time. The consistently high rates of binge drinking and polysubstance use among bisexual women deserve much closer attention based on the related health consequences.

Simultaneous use of marijuana and alcohol: Potential prevention targets among young adults who use alcohol

Simultaneous alcohol and marijuana use (SAM) such that their effects overlap has emerged as a behavior that is riskier than using either substance separately. It has been associated with high-risk binge drinking and driving while intoxicated during young adulthood, and it has been demonstrated to cause greater physical and mental impairment than use of alcohol or marijuana separately. To identify intervention and prevention targets specific to SAM, we examined the relationships between alcohol- and marijuana-specific beliefs and attitudes (risk factors) and self-reported SAM compared to non-simultaneous co-use (CAM) and alcohol use only in the past 30 days in a sample of young adults (n = 1,023, mean age = 23.17; SD = 0.43). Of those who reported drinking alcohol in the past 30 days, 20.7% reported SAM, 12.6% reported CAM, and 66.6% reported using only alcohol. Results from multinomial logistic regression analyses indicated that some marijuana-specific risk factors (e.g., belief that it is not at all wrong for someone their age to use marijuana) differentiated SAM or CAM from alcohol use only, but alcohol-specific risk factors generally did not. However, the perceptions that parents approved of their using marijuana or frequently drinking heavily were associated with a greater likelihood of SAM compared to CAM (OR ranged from 2.25 to 3.53). Findings point to the salience of individuals' attitudes and beliefs around marijuana use and their perception of parental approval of heavy drinking and marijuana use as potential targets for prevention programs targeting risk reduction among young adults.

Stress and Affect as Daily Risk Factors for Substance Use Patterns: an Application of Latent Class Analysis for Daily Diary Data

At the population level, use of multiple substances (or "co-use") is prevalent in young adulthood and linked with increased risk for experiencing substance-related harms. Less understood is the heterogeneity of substance use behaviors within individuals and across days, as well as the proximal predictors of these daily use patterns. The present study applied latent class analysis to daily diary data to identify daily substance use patterns and compare day-level class membership based on day-level stress and positive and negative affect among a higher-risk sample of young adult substance users. Participants (n = 152) completed up to 13 daily assessments of stress, affect, and substance use behavior. Among substance use days, five classes of days were identified: cannabis (some alcohol; 43% of days), alcohol-only (26%), vaping (some alcohol, cannabis; 24%), stimulant + alcohol (some cannabis, vaping; 4%), and cigarette-only (3%) days. Days with lower levels of perceived stress were significantly more likely to be alcohol-only Days relative to being days characterized by cigarette use, cannabis use, or multiple drug combinations. Days with higher levels of stress and negative affect were more likely to be cigarette-only days relative to cannabis and vaping days. Study findings document the wide range of substance use and co-use behaviors exhibited among young adults in daily life and highlight the importance of considering risk factors that correspond to days of problematic use patterns.

Illicit Drug Use and Associated Problems in the Nightlife Scene: A Potential Setting for Prevention

Illicit drug use is prevalent in the nightlife scene, especially at electronic dance music (EDM) events. The aim of the present study was to investigate illicit drug use patterns and consequences of drug use among frequent visitors of EDM events. Young adults (18-34 years old) who had visited at least six EDM events in Sweden during the past year participated in a web-based survey on drug use patterns and its consequences. Fifty-nine percent of participants had used illicit drugs during the past year, most often cannabis followed by ecstasy, cocaine, and amphetamine. Nightlife venues were identified as the main setting for the use of central stimulants, while cannabis was mostly used at home. Frequent alcohol and tobacco use was associated with illicit drug use. The most prevalent negative consequences of drug use were related to mental health, such as impairments in mood, sleep, and memory problems, but physical manifestations were also reported, such as palpitations and collapsing. These findings confirm that drug use is prevalent and associated with negative health effects among EDM nightlife attendees. The nightlife scene is a setting with promising potential to reach a high-risk target group with illicit drug use prevention interventions.

Symptoms of anxiety, depression, and borderline personality in alcohol use disorder with and without comorbid substance use disorder

OBJECTIVE

Alcohol use disorder (AUD) is highly comorbid with other substance use disorders (SUDs) as well as other psychiatric disorders, such as anxiety, depression, and Borderline Personality Disorder (BPD). However, studies of persons with AUD rarely account for its comorbidity with other SUDs. Some research suggests that BPD symptoms reflect an important connection between internalizing disorders and SUDs. The current study investigated: 1) the levels of trait anxiety and symptoms of depression and BPD in persons with an AUD as a function of comorbid SUDs (cannabis use disorder - CUD) and other substance use disorder (oSUD), and 2) the influence of BPD on the association between severity of overall lifetime SUD symptoms (AUD + CUD + oSUD) and both trait anxiety and symptoms of depression.

METHOD

Trait anxiety and symptoms of depression and BPD were assessed in 671 young adults (351 men; 320 women; mean age 21 years) separated into four groups: Controls (n = 185), AUD-only (134), AUD + CUD (n = 210), and AUD + oSUD (n = 142).

RESULTS

Trait anxiety and symptoms of depression and BPD were elevated in all AUD groups compared with controls, and in the AUD + oSUD group compared with all other groups as well. Structural models also indicated that BPD symptoms accounted for all of the variance in lifetime SUD symptoms associated with Trait Anxiety, and a significant portion of the variance in lifetime SUD symptoms associated with depression symptoms.

CONCLUSION

Results indicate that when AUD is comorbid with oSUD, it is associated with more severe AUD symptoms and higher levels of trait anxiety and symptoms of both depression and BPD. The results also indicate that BPD symptoms account for the majority of the variance in SUD symptoms associated with both trait anxiety and depression, suggesting that a considerable amount of the internalizing symptomatology in AUD/SUDs is associated with BPD psychopathology.

Disparities in health behaviors and outcomes at the intersection of race and sexual identity among women: Results from the 2011-2016 National Health and Nutrition Examination Survey

The purpose of this study was to explore potential differences in health behaviors and outcomes of sexual minority women (SMW) of color compared to White SMW, heterosexual women of color, and White heterosexual women. Data from 4878 women were extracted from the 2011 to 2016 National Health and Nutritional Examination Survey. The four-category independent variable (SMW of color, White SMW, heterosexual women of color, and White heterosexual women) was included in binary and multinomial logistic regression models predicting fair/poor self-reported health status, depression, cigarette smoking, alcohol, cannabis, and illicit drug use. Compared to White heterosexual women, SMW of color and heterosexual women of color had significantly higher odds of fair/poor self-reported health and lower odds of being a current or former smoker, binge drinking or using alcohol in the past year, being a former cannabis user, and ever using illicit drugs. In contrast, White SMW had significantly greater odds of depression, current smoking and cannabis and illicit drug use. Results of post-hoc tests indicated that the adjusted ORs for SMW of color differed significantly from those of White SMW for all outcomes, and did not differ significantly from those for heterosexual women of color for any outcome other than no binge drinking (OR = 0.34 vs. 0.67, p < 0.01) and current cannabis use (OR = 0.93 vs. 0.44, p < 0.01). SMW of color are more similar to heterosexual women of color than to White SMW in terms of depression, substance use, and self-reported health.

Prevalence and Characteristics of Borderline Intellectual Functioning in a Cohort of Patients With Polysubstance Use Disorder

Objective: To determine the prevalence and associated demographic and clinical features of borderline intellectual functioning (BIF) among individuals with polysubstance use disorder (pSUD). Methods: We applied a cross-sectional analytical design to data from the Norwegian STAYER study (n = 162), a cohort study of patients with a pSUD from the Stavanger University hospital catchment area. We used Wechsler Abbreviated Scale of Intelligence Full Scale IQ (FSIQ) to define BIF (FSIQ = 70-85) and non-BIF (FSIQ = >85) and collected demographic and clinical data using semi-structured interviews and self-reports on the Symptom Checklist 90-Revised (SCL-90-R) and the Satisfaction With Life Scale (SWLS). Results: The prevalence of BIF was 18% in the present study. The presence of BIF was associated with higher SCL-90-R GSI scores than in the non-BIF group. There were no significant differences between the BIF and non-BIF groups regarding age, gender, participation in meaningful daily activity, years of work experience, years of education, satisfaction with life, level of care, treatment attempts, age at substance-use onset, years of substance use, history of injecting drugs, or age of onset of injecting drugs. Conclusion: The present study confirmed a higher prevalence of BIF among patients with pSUD than expected from the distribution of IQ scores in a general population. Elevated SCL-90-R GSI scores suggested that BIF is associated with increased psychological distress in patients receiving treatment for pSUD. Further studies on this association, and its effect on treatment procedure and outcomes are strongly warranted.

Examining the Utility of a General Substance Use Spectrum Using Latent Trait Modeling

BACKGROUND

Polysubstance use (PSU; lifetime use of multiple substances) is common among individuals with problematic alcohol/substance use and is associated with poor prognosis and poor physical/mental health. Furthermore, simultaneous co-use of substances, such that drug effects overlap, is also common and related to unique risks (e.g. overdose). Despite the importance of PSU, current diagnostic systems continue to conceptualize problems with alcohol/substances as class-specific constructs (e.g. Stimulant Use Disorder), which essentially ignore many unique PSU processes.

METHODS

The current study modeled problems with alcohol, cannabis, stimulants, sedatives, opiates, and simultaneous co-use of these substances as a manifestation of a general substance use continuum versus as correlated class-specific constructs in a sample of young-adults(n = 2482) using confirmatory factor analysis. Utility of the models was evaluated by examining associations between the general substance use spectrum and class-specific latent factors with measures of anxiety, ADHD, adult antisocial problems, borderline symptoms, neuroticism, and intelligence in a subset of the sample(n=847).

RESULTS

Findings supported the conceptualization of problems with all substances, including co-use of substances, as being manifestations of a general substance use spectrum, as class-specific constructs were not differentially associated with other measures of psychological dysfunction. Examination of this general substance use spectrum indicated that all substances, separately and co-use, were robustly informative of this spectrum, but tended to discriminate between different severity levels.

DISCUSSION

The general substance use spectrum allows for integration of information from the use and co-use of all substances to provide better assessment of overall problems with substances compared to class-specific constructs.

Polysubstance use in rural West Virginia: Associations between latent classes of drug use, overdose, and take-home naloxone

BACKGROUND

Rural communities in the United States have been disproportionately affected by the opioid crisis. Little research has explored the relationship between polysubstance use and overdose experiences among people who inject drugs (PWID) in rural communities. We sought to identify classes of polysubstance drug use among rural PWID and evaluate the associations between polysubstance drug use classes, recent overdose experiences, and receipt of take-home naloxone (THN).

METHODS

We surveyed 420 PWID (June-July 2018) who had injected drugs in the previous 6 months in Cabell County, West Virginia. Participants were recruited from the local syringe services program and through street-based recruitment. We conducted a latent class analysis using 9 measures of injection and non-injection drug use and tested for associations with having experienced an overdose in the past 6 months and having received THN in the past 6 months.

RESULTS

We identified four substance use classes in our sample: polydrug/polyroute use (35.0% of the sample), polyroute stimulant/injection opioid use (33.3%), polyroute stimulant use (20.3%), and injection opioid use (11.3%). Overall, 42.6% of the sample had experienced an overdose in the past 6 months. The classes differed in terms of overdose (χ=91.53, p<0.001), with the polydrug/polyroute use class having the highest probability of overdose and the polyroute stimulants class having the lowest. Only 46.5% of participants had received THN, and probabilities differed between classes (χ=21.93, p<0.001). The polyroute stimulants/injection opioid use and polydrug/polyroute use classes had the highest levels of THN receipt while the polyroute stimulants use class had the least.

CONCLUSION

Among rural PWID in West Virginia, polysubstance use was prevalent and associated with overdose and THN acquisition. These analyses demonstrate the importance of scaling up naloxone distribution in rural settings. Overdose prevention initiatives are reaching persons at high risk of overdose, but expansion of services is needed.

Concurrent Alcohol and Opioid Use Among Harm Reduction Clients

BACKGROUND

Harm reduction services infrequently address alcohol use among clients using opioids, despite the evaluated risk of overdose or medical consequences for clients with viral infections. The purpose of this study is to assess concurrent alcohol and opioid use among syringe services and overdose prevention program participants predominately in southern Ohio and northern Kentucky.

METHODS

This is a cross-sectional study using self-report data (n = 1,142) pooled across regional overdose prevention programs and a mobile syringe services program. The outcome variable was concurrent use categorized as no concurrent alcohol, prescription opioid or heroin use; alcohol and heroin or prescription opioid use; and alcohol, prescription opioid and heroin use in the past three months.

RESULTS

The sample was predominantly white (95%), 56% were male and the mean age was 33 years old. Forty-seven percent of the clients had no concurrent use of alcohol and opioids; 20.1% reported concurrent use of alcohol and either heroin or prescription opioids; and 33.4% reported concurrent use of alcohol, heroin and prescription opioids in the past 3 months. Lifetime suicidal ideation and non-opioid drug use were associated with concurrent alcohol and opioid use in the multivariable model.

CONCLUSION

Harm reduction clients with concurrent alcohol and opioid use may warrant enhanced overdose prevention services. Syringe services and overdose prevention program participants may benefit from education or a brief intervention on alcohol consumption.

The changing patterns and correlates of population-level polysubstance use in Australian youth: a multi-group latent class analysis of nationally representative samples spanning 12 years

AIMS

To (1) identify population-level classes of polysubstance use among young Australians between 2004 and 2016, (2) test if these classes changed over the same period, in terms of class prevalence and probabilities of substance use within each class, and (3) identify demographic and health-related correlates of polysubstance use.

DESIGN

Repeated cross-sectional nationally representative household surveys.

SETTING

All Australian states/territories.

PARTICIPANTS

Young adult samples (aged 18-30 years; 58% females) from the National Drug Strategy Household Surveys (n = 20 350) MEASUREMENTS: Outcomes were the extent of past-year use of 10 licit (e.g. alcohol), and illicit substances (e.g. cannabis) were used to derive polysubstance use classes. The correlates were gender, age, psychological distress, general health, language background, personal income, education level, remoteness of residence and socio-economic index for area of residence.

FINDINGS

Three polysubstance use classes were consistently identified between 2004 and 2016 (SSABIC: 188349): minimal users (MU, ~60%), mainly tobacco, alcohol and cannabis users (TAC, ~30%) and extended range polysubstance users (POLY, ~10%). There were substantial changes in use of different substances within each class over the study period. For example, smoking decreased in all classes (P < 0.05), while harmful alcohol use only decreased in the first two classes (P < 0.05). Factors associated with TAC and POLY were similar over the study period. These included: being male and having an English-speaking background, a high level of psychological distress, suboptimal health and high personal income. Living in an affluent area was associated with reduced likelihood of being TAC, but an increased likelihood of being POLY.

CONCLUSION

At the population-level among young Australians between 2004 and 2016, six in 10 did not engage in polysubstance use; four in 10 used a limited range of substances (mainly alcohol, tobacco and cannabis) and one in 10 used an extended range of substances. Over time, the types of substance within the extended polysubstance use class changed substantially.

Patterns of polysubstance use and simultaneous co-use in high risk young adults

BACKGROUND

Polysubstance use (PSU) is associated with worse prognosis and poorer physical and mental health compared to single substance use. The current study provides information about PSU patterns by examining a diverse range of alcohol/substance use behaviors ranging from low-level experimentation to indicators of severe abuse. In addition, the current study, for the first time, examines how simultaneous co-use of multiple substances cluster with other more commonly studied PSU behaviors.

METHODS

Latent Class Analysis was used to identify patterns of substance use, in a sample of young-adults (n = 2098), using 25 items from the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA-II) including: items assessing severity of problems with alcohol, cannabis, stimulants, opiates, and sedatives; items assessing # of lifetime uses; items assessing simultaneous co-use of all combinations of substances. Then the association of class membership and age, antisocial and impulsive personality, experience seeking, anxiety, and neuroticism was examined using Multinomial Regression.

RESULTS

Fit indices (i.e. AIC, SSABIC, and entropy) and interpretability of classes supported a five-class solution: "Low Problems" (32% of sample), "Alcohol Primary" (11%), "Alcohol and Cannabis" (25%), "Moderate PSU" (23%), and "Severe PSU" (9%). Simultaneous co-use behaviors discriminated between lower and higher severity groups. Externalizing personality constructs robustly predicted membership in the "Moderate" and "Severe" PSU classes compared to the "Alcohol Primary" class.

CONCLUSIONS

PSU patterns followed an additive pattern of use with lower severity classes using alcohol/cannabis and more severe classes using other illicit substances in addition. Co-use items provided valuable information about PSU severity.

Polysubstance Use by Stimulant Users: Health Outcomes Over Three Years

OBJECTIVE

Studies show that stimulant users have varied substance use patterns and that polysubstance use is associated with poorer past or concurrent medical, mental health, and substance use outcomes. This study examined outcomes of substance use patterns prospectively.

METHOD

A latent class analysis was conducted to examine substance use patterns among adults using stimulants (n = 710; 38.6% women) at baseline, and the health and treatment utilization outcomes of different use patterns over the subsequent 3 years. To examine associations between latent class membership and outcomes, generalized estimating equation modeling was conducted.

RESULTS

Four classes of substance use patterns at baseline were identified, involving high use of (a) methamphetamine and marijuana (23%); (b) crack cocaine and alcohol (25%); (c) powder cocaine, alcohol, and marijuana (23%); and (d) nonprescribed opioids, alcohol, marijuana, crack cocaine, and powder cocaine (i.e., polysubstance [29%]). Polysubstance class members had poorer physical health and mental health status, and more severe substance use, over the subsequent 3-year period, than other class members. Regarding treatment utilization, polysubstance class members had more medical care utilization than crack cocaine class members, and more substance use treatment utilization than powder cocaine class members. The methamphetamine, crack cocaine, and powder cocaine classes did not differ from each other on any health or treatment utilization outcome.

CONCLUSIONS

People using stimulants commonly use other substances, and those whose polysubstance use includes nonprescribed opioids have especially poor health outcomes.

The effects of sub-anesthetic ketamine plus ethanol on behaviors and apoptosis in the prefrontal cortex and hippocampus of adolescent rats

Ketamine has become increasingly popular in adolescent drug abusers worldwide. Meanwhile, alcohol is usually used by ketamine users. However, little work has been conducted to examine the chronic combined effects of ketamine and ethanol on adolescent brain. Here we probed into the effects of chronic administration of ketamine at recreational doses alone or combined with ethanol on behaviors and neuron damage in an adolescent rat model. 28-day old rats were treated with either 20 or 30 mg/kg ketamine plus or not plus 10% ethanol daily for 21 days. Depressive like behaviors, anxiety like behavior and memory impairment were tested using open field test, forced swimming test, elevated plus maze and Morris water maze. Apoptosis in prefrontal cortex (PFC) and hippocampus (HIP) were determined by the TdT-mediated dUTP Nick-End Labeling (TUNEL) and protein and mRNA levels of caspase-3, Bax and Bcl-2. Results show that co-application of ketamine and ethanol significantly increased immobility time in the forced swimming test, up-regulated TUNEL positive cells and both protein and mRNA expressions of caspase-3 and Bax, compared with the control group and ketamine and ethanol use alone groups in the PFC, but not in the HIP. Our study suggests that chronic co-administration of ketamine and ethanol results in depressive-like behavior and the caspase-dependent apoptosis in the PFC of adolescent rats' brains.

Identifying behavioural characteristics of tobacco product and e-cigarette use clusters: A repeat cross-sectional analysis

BACKGROUND

Youth may use a variety of tobacco products and e-cigarettes. However, there is a lack of evidence for the combinations of tobacco products and e-cigarettes commonly used by youth in Canada and whether youth from different usage classes share similar characteristics.

METHODS

A cohort of 9th grade students from Ontario, Canada was identified at baseline (2013-14) of the COMPASS study (n = 4651). Classes of youth that currently use similar combinations of tobacco products and e-cigarettes were identified at baseline, one (FY1) and two years later (FY2) using latent class analysis. Multinomial logistic regression models identified demographic and behavioural characteristics (e.g., environmental influences, substance use behaviours, etc.) of youth in current tobacco and e-cigarette use classes relative to youth in non-current use classes.

RESULTS

At baseline, a three-class model was identified as best, while a four-class model was identified at FY1 and FY2. A non-current use group and an all-product use group were identified every year. Students that reported having friends that smoked cigarettes, binge drinking, and using marijuana were more likely to be classified into a current use class.

CONCLUSIONS

Tobacco cigarettes were more likely to be used with other products than on their own. An all-product use group was identified across all three survey waves and the prevalence of this group increased over time. Given that many youth in this study used more than one tobacco product or e-cigarette and commonly reported binge drinking and using marijuana, prevention and cessation activities should address the use of multiple products.

Nightlife and Drug Use in Tbilisi, Georgia: Results of an Exploratory Qualitative Study

Tbilisi is fast becoming a regional hub for electronic dance music. This study describes the use of illicit psychoactive drugs by frequent nightclub visitors in a club setting. We conducted 16 qualitative in-depth interviews with young nightclubbers with a history of drug use in Tbilisi. The majority of respondents had experience with two or more drugs consumed in a club setting, with the most prevalent substances being MDMA/ecstasy, amphetamines, and synthetic cannabinoids. Most respondents had limited information regarding the drugs they consumed. Often this information was provided by dealers or friends and was limited to the name of the drug (but not the substance) and its expected effects. Receiving often unknown substances from unknown people was prevalent. The majority of respondents reported combining psychoactive substances with alcohol, or mixing the use of other substances. Participants by their own account indicated a lack of knowledge about the adverse effects of drugs, as well as an ignorance of overdose signs and response strategies. Study findings may guide future efforts to investigate the prevalence and context of club drug use in the country, to assess health risks associated with it, and to propose strategies to mitigate those risks.

A latent class analysis of the past-30-day substance use patterns among lifetime cocaine users: Findings from a community sample in North Central Florida

Objectives

Cocaine use is increasing and many cocaine users engage in polysubstance use. Within polysubstance use, relationships among use of individual substances are necessarily complex. To address this complexity, we used latent class analysis (LCA) to identify patterns of polysubstance use among lifetime cocaine users and examine associations among these patterns, demographics, and risk profiles.

Methods

Members of HealthStreet, an ongoing community engagement program, were asked about lifetime and past 30-day use of cocaine, alcohol, tobacco, marijuana, and prescription medications, mental health conditions, recent Emergency Department (ED) visits and demographics. LCA was used to identify classes of past 30-day polysubstance use among individuals who endorsed lifetime cocaine use. Multinomial logistic regression identified factors associated with these classes.

Results

Among 1797 lifetime cocaine users, a five-class LCA model was identified: 1) past 30-day tobacco use only (45%), 2) past 30-day alcohol, marijuana and tobacco use (31%), 3) past 30-day tobacco, prescription opioid and sedative use (13%), 4) past 30-day cocaine, alcohol, marijuana and tobacco use (9%), 5) past 30-day cocaine and multiple polysubstance use (2%). Demographics, ED visits and mental health conditions were associated with class membership.

Conclusions

Approximately 11% of lifetime cocaine users used cocaine in the past 30 days with two different concurrent substance use patterns. Prescription medication (opioids and sedatives) and complex polysubstance use patterns were stronger indicators of negative outcomes than current cocaine use. Cocaine was not used frequently with other stimulants. In addition to polysubstance use, prescription medication use should be targeted for intervention among lifetime cocaine users.

Non-medical use of pharmaceutical opioids with and without other illicit substances in Australia: Prevalence and correlates

INTRODUCTION AND AIMS

To estimate the prevalence of non-medical use of pharmaceutical opioids and examine the socio-demographic, psychological, health and behavioural correlates and type of opioids used.

DESIGN AND METHODS

Data from the Australian National Drug Strategy Household Survey 2016 was used. The sample consisted of. 23 448 participants aged over 14 years (54% female). The key measure was opioid use status in the past year. Based on participants' responses to questions about their substance use in the past 12 months, they were grouped into four opioid use status: (i) No illicit substance use (ISU) and no non-medical use of pharmaceutical opioids (NMUPO); (ii) ISU but no NMUPO; (iii) NMUPO but no ISU; and (iv) NMUPO and ISU.

RESULTS

The prevalence non-medical pharmaceutical opioid use was 3.56%. Two-thirds of them engaged in NMUPO but no ISU; one-third engaged in NMUPO and ISU. Younger people were more likely to use pharmaceutical opioids in addition to other illicit drugs, while older people were more likely to only use pharmaceutical opioids. Alcohol risk and daily smoking were associated with using pharmaceutical opioids and other illicit drugs, but not with pharmaceutical opioids only. Those who reported only using pharmaceutical opioids were more likely to use over-the-counter codeine products.

DISCUSSION AND CONCLUSIONS

Over 700 000 Australian used pharmaceutical opioids for non-medical purpose. Among users, two-thirds used only opioids and one-third used opioids in addition to other illicit drugs. Profile of these two types of users were substantially different. Future prevention efforts targeting different type of opioids users may need to be optimised based on their profiles.

Effects of ketamine use on psychotic disorders and symptoms in male, methamphetamine-dependent subjects

BACKGROUND

Repeated and extensive methamphetamine or ketamine use may cause psychotic symptoms. Whether the chronic and combined use of these substances has a greater psychotic effect is still unknown.

OBJECTIVES

To examine the effect of different levels of ketamine use on psychotic disorders and symptoms in male methamphetamine-dependent subjects.

METHODS

A cross-sectional, structured, and clinical interview method was used to examine the differences in DSM-IV-TR Axis I psychotic disorders and symptoms among methamphetamine-dependent subjects in three categories: 205 with no ketamine use, 38 with occasional ketamine use, and 72 with ketamine abuse or dependence from compulsory rehabilitation centers.

RESULTS

Both methamphetamine-dependent subjects with occasional ketamine use and those with ketamine abuse or dependence had a higher prevalence of psychotic disorders than those who had not used ketamine (p = 0.021; p < 0.001). Subjects who used ketamine occasionally had a higher prevalence of referential and persecutory delusions (p < 0.001; p = 0.013) and auditory hallucinations (p = 0.030), and those with ketamine abuse or dependence had a higher prevalence of referential and persecutory delusions (p = 0.005; p = 0.021), compared with those who had not used ketamine. There was no significant difference in any psychotic disorders or symptoms between subjects with occasional ketamine use and those with ketamine abuse or dependence.

CONCLUSIONS

The combination of methamphetamine and ketamine was associated with greater psychotic effects than methamphetamine alone. Both occasional ketamine use and ketamine abuse or dependence were associated with increased psychotic symptoms and disorders in methamphetamine-dependent males.

Harm reduction strategies related to dosing and their relation to harms among festival attendees who use multiple drugs

INTRODUCTION AND AIMS

Polysubstance users are a high-risk population for negative health-related consequences. Although some studies have described harm reduction strategies adopted by polysubstance users, studies have not examined their effectiveness in minimising health-related consequences. We aimed to identify dosing-related harm reduction strategies in a sample of polysubstance-using dance festival attendees, and explore the relationship between harm reduction strategies and self-reported adverse health consequences.

DESIGN AND METHODS

Data were examined for 1226 past-year dance festival attendees who self-identified as past-year multiple drug users. We conducted bivariable and multivariable analyses to explore relationships between six dosing-related harm reduction strategies and 13 self-reported adverse consequences.

RESULTS

Self-reported use of dosing-related harm reduction strategies was prevalent, mainly avoidance of mixing depressants (69.2%) and setting limits on quantity (62.2%). Frequent users of harm reduction strategies reported experiencing fewer adverse health consequences (P values < 0.05). Those who reportedly set limits on quantity were at decreased odds of experiencing a bad mood after drug use, sexual difficulties while under drug influence, injuries or fractures while under drug influence, and involvement in fights or being attacked while under drug influence (P values < 0.05). Moreover, those who report frequently avoid mixing depressants were at decreased odds of experiencing headache, loss of consciousness, drop in blood pressure, injuries of fractures, and fights or attacks (P values < 0.05).

DISCUSSION AND CONCLUSIONS

Adoption of dosing-related harm reduction strategies appears to be associated with less drug-related harm among polysubstance-using festival attendees. Findings may inform organisations and policymakers in the designing of harm reduction interventions with this population.

Polysubstance Use Among Veterans in Intensive PTSD Programs: Association With Symptoms and Outcomes Following Treatment

Objective: A distinct group of patients has recently been described who experience polysubstance use disorder characterized by use of multiple addictive substances. This study examines baseline characteristics and longitudinal outcomes of a group of such patients in specialized intensive Veterans Health Administration posttraumatic stress disorder (PTSD) programs and followed 4 months after discharge. Methods: Patients with diagnosed PTSD or subsyndromal PTSD and who used a single substance at baseline were compared to those who used two or three and more than three different addictive substances on measures of PTSD symptom severity and functioning. Comparisons were also adjusted for differences in total days of any substance use and other potentially confounding factors. Patients were reclassified according to the number of substances used at follow-up and again compared on symptoms and functioning. Results: Bivariate analysis of baseline data (N = 8,240) showed frequent polysubstance use (n = 3,695, 44.8% of the sample) and that use of greater numbers of substances was associated with more severe PTSD symptoms as well as more total days of substance use. At follow-up after treatment, 58.2% of the original sample (n = 4,797) was assessed. Polysubstance use was less frequent (n = 756, 15.8% of the follow-up sample), but showed a similar association with more severe symptoms, although differences were attenuated after adjusting for total days of substance use. Conclusions: Polysubstance use, conceptualized within the multimorbidity perspective, is associated with increased severity of PTSD symptoms among veterans with dual diagnoses requiring complex interventions, the evaluation of which will require innovative trial designs.

Prevalence and characteristics associated with concurrent smoking and alcohol misuse within Australian general practice patients

Objectives This study sought to determine, among a large sample of Australian general practice patients: (1) the prevalence of smoking among different levels of alcohol misuse; and (2) whether the associations between demographic characteristics and alcohol use differ according to smoking status. Methods A cross-sectional survey was administered from 2010 to 2011 to 3559 patients from 12 Australian urban general practices. Patients reported their demographic details, smoking status and their alcohol intake. Results The overall prevalence of reported concurrent smoking and alcohol misuse was 7.8%. Smokers were 3.81-fold more likely to have a higher level of alcohol consumption than non-smokers (95% confidence interval 3.13-4.63; P<0.0001). There was evidence that smoking was an effect modifier of the relationship between alcohol misuse and chronic illness. Conclusions There was an increasing prevalence of smoking with increasing level of alcohol consumption. In addition, those with chronic conditions who smoked had greater odds of higher levels of alcohol consumption. Preventative interventions for these substances are needed to reduce the burden associated with concurrent smoking and alcohol misuse. What is known about the topic? Tobacco and alcohol are the most commonly used substances and contribute to over 10million deaths annually. The risk of disease is high when using either of these substances, however, concurrent use is associated with a greatly compounded risk. Australian data is limited regarding the prevalence of concurrent tobacco and alcohol misuse, however, international studies suggest variation in prevalence rates between different clinical settings. What does this paper add? This study examined the prevalence of concurrent smoking and alcohol misuse among different levels of alcohol misuse severity within an Australian general practice setting. Additionally it explored whether the associations between demographic characteristics and alcohol use differ according to smoking status. What are the implications for practitioners? This study has important implications for disease prevention and the delivery of preventive health services by general practitioners. Considering one in 100 clinical treatments provided in general practice relate to preventative smoking or alcohol counselling, it is critical that efforts are made to ascertain risk factors such as smoking and alcohol misuse to increase treatment rates. General practitioners should consider screening for smoking and alcohol misuse opportunistically during routine clinical encounters, as well as screening for smoking or alcohol misuse if one or the other is present.

Patterns and Correlates of Tobacco and Cannabis co-use by Tobacco Product Type: Findings from the Virginia Youth Survey

BACKGROUND

Cannabis use is more common among tobacco users than nonusers, and co-use (i.e., use of both substances individually) may be increasing. Better understanding of patterns and correlates of co-use is needed. The current study aimed to compare rates and correlates of tobacco and cannabis co-use by tobacco product among youth.

METHODS

High school students who completed the 2013 Virginia Youth Survey and reported past 30-day tobacco use (cigarette, smokeless tobacco, cigar) were included (n = 1390). Prevalence of past 30-day tobacco-only and cannabis co-use was calculated. Demographic, tobacco, and other substance use characteristics were compared by co-use status. Multivariate logistic regression models examined correlates of co-use overall and by tobacco product.

RESULTS

Over half of tobacco users were co-users. Poly-tobacco use, particularly combusted tobacco, was more prevalent among co-users. Past 30-day alcohol use and lifetime other illegal drug use/prescription drug misuse were common correlates of co-use. Black Non-Hispanic (NH) race/ethnicity was associated with co-use when restricted to cigarette users. "Other" race/ethnicity was associated with co-use in the overall model and when restricted to cigar users. Past 30-day cigarette smoking was associated with co-use in all models except among cigar smoking co-users. Conclusions/Importance: Rates and correlates of tobacco and cannabis co-use were not uniform and differed by tobacco product type. Tobacco and cannabis co-users may be at greater risk for negative health effects associated with inhaled tobacco and other risky substance use. The efficacy of prevention efforts may be improved if risk factors associated with product-specific co-use are considered.

Polydrug use among heroin users in Cleveland, OH

BACKGROUND

Since 2000, heroin use patterns have shifted within the United States. How this change may relate to polydrug use among local heroin users is unknown. Although polydrug use has been studied, user perceptions of drug use in terms of health risks, arrest risk, availability, cost, liking, and dependence have not been considered.

METHODS

Data are presented from a brief, face-to-face survey conducted in 2016 of 200 non-in-treatment heroin users from Cleveland, OH. We assessed the use of and attitudes on alcohol, marijuana, methamphetamine, heroin, crack cocaine, powder cocaine, and prescription drugs. We estimated polydrug (concurrent past month) use with cluster analysis and latent profiles. Regression analysis estimated the strength of relationships between attitudes and frequency of use.

RESULTS

We identified five clusters: Cluster 1 used heroin concomitantly with alcohol and occasionally crack; Cluster 2 used heroin and crack cocaine daily; Cluster 3 used heroin daily and almost exclusively; Cluster 4 used heroin and marijuana daily; and Cluster 5 were part-time drug users. Drug use frequency was associated with liking and being anxious when drugs could not be obtained. High perceived availability of heroin and cocaine and low cost facilitated polydrug use.

CONCLUSIONS

Understanding polydrug use clusters among heroin users is important for addressing the larger opioid epidemic. Users' perceptions of a drug's availability and cost appeared to facilitate polydrug use and justify more detailed future research on drug access.

Polysubstance Use by Stimulant Users: Health Outcomes Over Three Years

OBJECTIVE

Studies show that stimulant users have varied substance use patterns and that polysubstance use is associated with poorer past or concurrent medical, mental health, and substance use outcomes. This study examined outcomes of substance use patterns prospectively.

METHOD

A latent class analysis was conducted to examine substance use patterns among adults using stimulants (n = 710; 38.6% women) at baseline, and the health and treatment utilization outcomes of different use patterns over the subsequent 3 years. To examine associations between latent class membership and outcomes, generalized estimating equation modeling was conducted.

RESULTS

Four classes of substance use patterns at baseline were identified, involving high use of (a) methamphetamine and marijuana (23%); (b) crack cocaine and alcohol (25%); (c) powder cocaine, alcohol, and marijuana (23%); and (d) nonprescribed opioids, alcohol, marijuana, crack cocaine, and powder cocaine (i.e., polysubstance [29%]). Polysubstance class members had poorer physical health and mental health status, and more severe substance use, over the subsequent 3-year period, than other class members. Regarding treatment utilization, polysubstance class members had more medical care utilization than crack cocaine class members, and more substance use treatment utilization than powder cocaine class members. The methamphetamine, crack cocaine, and powder cocaine classes did not differ from each other on any health or treatment utilization outcome.

CONCLUSIONS

People using stimulants commonly use other substances, and those whose polysubstance use includes nonprescribed opioids have especially poor health outcomes.

Concurrent use of alcohol with other drugs and DSM-5 alcohol use disorder comorbid with other drug use disorders: Sociodemographic characteristics, severity, and psychopathology

BACKGROUND

Little is known about the sociodemographic profiles, the intensity of drinking, the severity of alcohol use disorder (AUD), and psychopathology among individuals with specific patterns of concurrent alcohol and drug use and AUD and other drug use disorders (DUDs) comorbidity.

METHODS

Data were from the National Epidemiologic Survey on Alcohol and Related Conditions-III. We examined sociodemographic correlates and psychopathology among individuals with specific patterns of concurrent use of alcohol and drug and AUD-DUD comorbidity relative to alcohol use or AUD only, respectively, using multinomial logistic regression. We also examined whether concurrent alcohol and drug use and AUD-DUD comorbidity increased the intensity of drinking and severity of AUD, respectively.

RESULTS

The majority (62.0%) of past-year drinkers used only alcohol. The 12-month prevalence of AUD only was 53.5%. Individuals with concurrent use of alcohol and drugs and AUD-DUD comorbidity were more likely to be men, younger, never/previously married, with lower education and income (odds ratios (ORs) ≥ 1.2). Concurrent use of alcohol and drugs and AUD- DUD comorbidity groups were more likely to experience psychopathology than the alcohol use only and AUD only groups, respectively (ORs ≥ 1.3). The intensity of drinking was greater among the concurrent use groups relative to the alcohol use only group, while the severity of AUD was greater among AUD-DUD comorbidity groups relative to the AUD only group.

CONCLUSIONS

Research on consequences and treatment outcome of concurrent use of alcohol and drugs and AUD-DUD comorbidity is warranted to inform the development of more effective prevention/intervention programs.

Using Facebook to address smoking and heavy drinking in young adults: Protocol for a randomized, controlled trial

INTRODUCTION

Tobacco and alcohol often are used simultaneously by young adults, and their co-use is associated with greater health consequences than from single use. Social media platforms offer low cost and highly accessible channels to reach and engage young people in substance use interventions. The current trial seeks to compare the Facebook Tobacco Status Project (TSP) smoking cessation intervention to an intervention targeting both tobacco use and heavy episodic drinking (TSP + ALC) among young adults who use both substances.

METHODS

This randomized clinical trial will evaluate the feasibility and initial efficacy of TSP + ALC compared to TSP with 225 US young adult smokers reporting heavy drinking. Participants will be recruited online and randomized to one of two conditions (TSP or TSP + ALC), both with assignment to a Facebook group tailored to readiness to quit smoking. Groups will receive a 90-day intervention including daily Facebook postings and weekly live counseling sessions. The TSP + ALC group will include content related to alcohol use. All participants will be offered a 2-week introductory supply of nicotine patch. Participants will complete baseline, 3-, 6-, and 12-month online assessments of substance use and other health risk behaviors. The primary efficacy outcome is biochemically-verified 7-day point prevalence abstinence. Secondary outcomes include alcohol and tobacco use, combined use, and thoughts about each substance.

DISCUSSION

This trial examines an innovative and scalable approach to engaging young adults online in tobacco and alcohol use treatment. Study findings will inform digital health interventions and best practices for treating multiple substance use in young adults.

Polysubstance use and misuse or abuse of prescription opioid analgesics: a multi-level analysis of international data

Increasing mortality and morbidity associated with opioid analgesics has led to concerns about their misuse and abuse, even when obtained through a prescription. These concerns have been most pronounced in the United States, but limited data make it difficult to determine whether it is a problem in other countries. We investigated opioid analgesic misuse and abuse in participants from the Global Drug Survey 2015 resident in the United States (N = 1334), United Kingdom (N = 1199), France (N = 1258), Germany (N = 866), and Australia (N = 1013) who had used at least 1 prescription opioid analgesic medication in the past year. We also investigated the relationship with polysubstance use, one of the most consistent predictors of problematic opioid analgesic use. Data included misuse and abuse of codeine, hydrocodone, oxycodone, and tramadol; ability to obtain a prescription; different sources for obtaining drugs; and past-year use of benzodiazepines and illicit drugs. In multilevel models, country of residence accounted for less than 3% of the variance in opioid analgesic misuse or abuse. Adjusting for country of residence and sociodemographic factors, use of illicit drugs and benzodiazepines was associated with 4-fold greater odds of misuse (odds ratio 4.36, 95% confidence interval 3.29-5.93) and 6-fold greater odds of abuse compared with not using either drug (odds ratio 6.49, 95% confidence interval 4.0-10.48), although the strength of the association with abuse varied by country. Misuse and abuse by those prescribed opioid analgesics seem to be a problem that is not limited to the United States and warrant attention on an international scale.

Polysubstance use profiles among electronic dance music party attendees in New York City and their relation to use of new psychoactive substances

BACKGROUND

Electronic Dance Music (EDM) party attendees are often polysubstance users and are at high risk for use of new psychoactive substances (NPS). We sought to identify patterns of use of common illegal drugs among EDM party attendees, sociodemographic correlates, and use of NPS as a function of patterns of use of more common drugs to inform prevention and harm reduction.

METHOD

Using time-space-sampling, 1045 individuals aged 18-40 were surveyed entering EDM parties in New York City. We queried past-year use of common illegal drugs and 98 NPS. We conducted latent class analysis to identify polysubstance use profiles of use of eight common drugs (i.e., ecstasy, ketamine, LSD, mushrooms, powder cocaine, marijuana, amphetamine, benzodiazepines). Relationships between drug classification membership and sociodemographics and use of drugs within six NPS categories were examined.

RESULTS

We identified four profiles of use of common drugs: non-polysubstance use (61.1%), extensive polysubstance use (19.2%), moderate polysubstance use/stimulants (12.8%), and moderate polysubstance use/psychedelics (6.7%). Those in the moderate/psychedelic group were at higher odds of using NPS with psychedelic-type effects (2C, tryptamines, and other "new" psychedelics; Ps<0.05). Extensive polysubstance users were at increased odds of reporting use of 2C drugs, synthetic cathinones ("bath salts"), tryptamines, other new (non-phenethylamine) psychedelics, new dissociatives, and synthetic cannabinoids (Ps<0.05).

CONCLUSION

NPS preference is linked to the profile of use of common drugs among individuals in the EDM scene. Most participants were identified as non-polysubstance users, but findings may help inform preventive and harm reduction interventions among those at risk in this scene.

Concurrent and Simultaneous Use of Cannabis and Tobacco and Its Relationship with Academic Achievement amongst University Students

The combined use of cannabis and tobacco is frequent in Europe. Few studies have nonetheless explored this pattern of consumption and its relationship with academic achievement in Spanish population. The aim of the present study was to analyze (1) the frequency of four patterns of polydrug use the last year (non-dual users of cannabis and tobacco; concurrent users: cannabis and tobacco separately; simultaneous users: tobacco in cannabis "joints"; simultaneous users: tobacco in cannabis joints alongside alcohol) by gender and age; (2) grade point average (GPA) by gender and age; (3) the association between the frequency of the four patterns of use and the GPA amongst a sample of 477 Spanish university students. The use of cannabis and tobacco (concurrent and simultaneous) and GPA were assessed by means of self-reported questionnaires. Statistically significant differences were found for the GPA with respect to gender. The GPA by the non-dual users of cannabis and tobacco was significantly higher than the GPA corresponding to the concurrent and simultaneous users. The combined use of cannabis and tobacco, regardless of the type of use (concurrent or simultaneous), is moderately related to poor academic achievement amongst university students.