Patterns of concurrent substance use among nonmedical ADHD stimulant users: results from the National Survey on Drug Use and Health

High-dose benzodiazepine use and QTc interval prolongation, a latent class analysis study

Benzodiazepine (BDZ) addiction is a widespread and multifaceted phenomenon. For many patients, especially females, the concomitant use of other drugs also increases their risk of QTc prolongation, possibly leading to complications such as seizures and even sudden death. However, the relationship between BDZ use and QTc prolongation is currently unclear. The present study aims to examine patterns of polysubstance use among a sample of Italian adults with BDZ dependence in relation with their QTc prolongation risk. We used Latent Class Analysis (LCA) on data collected from 251 inpatients of the Addiction Medicine Unit in Verona to group patients into three classes according to their substance use and their QTc prolongation risk. Results showed no significant relationship between QTc prolongation and BDZ use in any of the classes considered. We conclude that BDZs, even if used long-term and at high dosages, can be considered safe in terms of cardiovascular complications for patients.

Differing Behaviors Around Adult Nonmedical Use of Prescription Stimulants and Opioids: Latent Class Analysis

BACKGROUND

The availability of central nervous system stimulants has risen in recent years, along with increased dispensing of stimulants for treatment of, for example, parent-reported attention-deficit/hyperactivity disorder in children and new diagnoses during adulthood. Typologies of drug use, as has been done with opioids, fail to include a sufficient range of behavioral factors to contextualize person-centric circumstances surrounding drug use. Understanding these patterns across drug classes would bring public health and regulatory practices toward precision public health.

OBJECTIVE

The objective of this study was to quantitatively delineate the unique behavioral profiles of adults who currently nonmedically use stimulants and opioids using a latent class analysis and to contrast the differences in findings by class. We further evaluated whether the subgroups identified were associated with an increased Drug Abuse Screening Test-10 (DAST-10) score, which is an indicator of average problematic drug use.

METHODS

This study used a national cross-sectional web-based survey, using 3 survey launches from 2019 to 2020 (before the COVID-19 pandemic). Data from adults who reported nonmedical use of prescription stimulants (n=2083) or prescription opioids (n=6127) in the last 12 months were analyzed. A weighted latent class analysis was used to identify the patterns of use. Drug types, motivations, and behaviors were factors in the model, which characterized unique classes of behavior.

RESULTS

Five stimulant nonmedical use classes were identified: amphetamine self-medication, network-sourced stimulant for alertness, nonamphetamine performance use, recreational use, and nondiscriminatory behaviors. The drug used nonmedically, acquisition through a friend or family member, and use to get high were strong differentiators among the stimulant classes. The latter 4 classes had significantly higher DAST-10 scores than amphetamine self-medication (P<.001). In addition, 4 opioid nonmedical use classes were identified: moderate pain with low mental health burden, high pain with higher mental health burden, risky behaviors with diverse motivations, and nondiscriminatory behaviors. There was a progressive and significant increase in DAST-10 scores across classes (P<.001). The potency of the opioid, pain history, the routes of administration, and psychoactive effect behaviors were strong differentiators among the opioid classes.

CONCLUSIONS

A more precise understanding of how behaviors tend to co-occur would improve efficacy and efficiency in developing interventions and supporting the overall health of those who use drugs, and it would improve communication with, and connection to, those at risk for severe drug outcomes.

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.

Survey of substance use among adolescent drug offenders referred from juvenile courts in Taiwan: Clinical epidemiology of single versus multiple illicit substance use

BACKGROUND

Substance use during adolescence might cause substantial health burden. Little is known regarding profiles of multiple illicit substance users compared to single illicit substance users in adolescent population in Taiwan.

METHODS

We enrolled 106 adolescent illicit drug users who received addiction treatment referred by juvenile courts in Taiwan between September, 2016 and September, 2021. We divided them into two groups: single versus multiple illicit drug users, and further compared their socio-demographic characteristics, psychiatric and substance comorbidities. The independent t test or Mann-Whitney U test was used for continuous variables and Pearson's chi-square test for nominal variables. Multivariate logistic regression was used to examine the suicide and violence risk among adolescents.

RESULTS

71.7% of participants were multiple illicit drug users while 28.3% of them were single drug users. Multiple illicit substance users were more likely to use methamphetamine (p = 0.005), ketamine (p < 0.001), new psychoactive substance (NPS) (p < 0.001), MDMA (p = 0.003), and nitrous oxide (p < 0.001) compared to single illicit substance users. In addition, multiple illicit drug users were more likely to have ADHD (p = 0.030), major depressive disorder (p = 0.050), and lifetime suicidal attempts (p = 0.048) compared to single illicit drug users. In further analysis (NPS vs. traditional drugs), we found NPS users tended to use larger numbers of illicit drugs (p < 0.001) and were more likely to have substance-induced psychotic disorder (p = 0.008), ADHD (p = 0.011), suicidal attempts (p = 0.020).

CONCLUSION

Our findings highlight the distinct profiles of multiple illicit drug users compared to single illicit drug users among adolescent population. High suicidality and high psychiatric comorbidities in multiple illicit drug users call for special need for suicide screening and a more integrated care incorporating psychiatric and substance treatment.

Latent Classes of Substance Use in Young Adults - A Systematic Review

Background: This systematic review provides an overview of studies on latent classes related to the substance use among young adults (18-25 years). Identifying these classes helps to detect high-risk groups, setting a base for selective prevention.Methods: This systematic literature review included peer-reviewed studies (published up to February, 2021) that identified latent classes and investigated predictors of latent classes relating to the use of marijuana, alcohol and/or other substances within samples of young adults.Results: Twenty studies (sample sizes N = 171 to N = 21945) met the inclusion criteria. 14 studies identified 'low-level engagers', 'light alcohol and tobacco use', 'heavy alcohol and tobacco use' and 'heavy use/polysubstance use' classes. Four studies differentiated within the 'heavy/polysubstance' class and found 'traditional clubdrugs', 'hallucinogens' and 'wide-range illicit drugs' classes. Male gender and white race predicted membership of the 'heavy use/polysubstance use' class consistently across studies. Other predictors of polysubstance use that were consistent across studies were peer substance use, depressive symptoms, parental drinking and participating in an honor society.Conclusions: The investigated predictors of class membership provide insight into social settings and characteristics that predict heavy use or polysubstance use. They can contribute to the development of effective prevention interventions by allowing for a more targeted approach.

Amphetamine-Type Stimulant Dependence and Association with Concurrent Use of Cocaine, Alcohol, and Cannabis: A Cross-Sectional Study

INTRODUCTION

Amphetamine-type stimulants (ATSs) are the second most commonly used class of illegal substances in Europe. Although concurrent substance use has been subject to research, little is known about associations between concurrent use of cocaine, alcohol, or cannabis and ATS dependence. We expect that the concurrent use of any of the substance, especially cannabis and cocaine, is associated with ATS dependence.

METHODS

Cross-sectional data were gathered within the European ATTUNE study in 2018/2019. Participants (N = 721) were asked about their consumption patterns and social, psychological, and economic situation. Multivariate logistic regressions were carried out for associations between ATS dependence and use combinations of frequent cocaine, alcohol, or cannabis, with the reference group of no frequent concurrent use (model 1). Model 2 calculated associations for ATS dependence with lifetime methamphetamine use for respective use combinations.

RESULTS

The study population was on average 28.9 years old (SD = 7.7), with the majority being male (63.5%). In model 1, the adjusted odds ratio (aOR) for frequent alcohol use was 0.70 (confidence interval [CI] 0.41-1.20). Similar results were shown for model 2 (aOR 0.82, CI 0.42-1.62). Frequent cannabis use significantly reduced the chance for ATS dependence by 50% in adjusted model 1 (aOR 0.50, CI 0.28-0.89) and by 62% in model 2 (aOR 0.38, CI 0.18-0.82). For frequent cocaine use, models 1 and 2 report an aOR at 1.37 (CI 0.58-3.25) and 2.39 (CI 0.77-7.43), although not statistically significant. Frequent users of all 3 substances had a significant 3-fold chance for ATS dependence (model 1: aOR 2.98, CI 1.16-7.63; model 2: aOR 2.95, CI 1.02-8.58).

DISCUSSION

Against initial hypotheses, frequent concurrent use of alcohol or cannabis generally decreased chances for ATS dependence. An explanation could be the study population, which consists of many irregular users of ATS, who mainly consume alcohol or cannabis. Cocaine generally increased chances, although results were not significant. The frequent use of all 3 substances together with ATS in the last year was significantly associated with dependence, thus reporting important information for treatment services. Further research is needed for disentangling causal relationships underlying these associations and for pinpointing consequences for relapse prevention and retention success.

Polysubstance Use Patterns Among High Dose Benzodiazepine Users: A Latent Class Analysis and Differences Between Male and Female Use

Benzodiazepines (BZDs) represent one of the most widely used groups of pharmaceuticals, but if used for long periods of time they are associated with dependence and an increased risk of harmful effects. High-dose (HD) BZD dependence is a specific substance use disorder associated with a poor quality of life. It is especially important to pinpoint differences in HD BZD addict subgroups in order to tailor treatment to the individual's specific needs, also considering possible comorbidities with other substance use disorders. We conducted a study to evaluate HD BZD dependence (converted doses to diazepam equivalents, mg) in an Italian sample of 1,354 participants. We also investigated if and to which extent participants co-used other substances (alcohol, tobacco, cannabis/cannabinoids, cocaine, and heroin). We then performed latent class analysis (LCA) to identify the use patterns of these substances, finding three classes: participants in Class 1 (4.3% of the sample) had the highest probability of also using cocaine and alcohol (Polysubstance BZD users); Class 2 comprised subjects with the highest probability of being former heroin, cocaine, THC, and alcohol users (Former polysubstance BZD users); Class 3 represented mono-dependence BZD users (78.5% of the sample) and was the most prevalent among women, while young men were most prevalent in Class 1. The present study underlines different characteristics in HD BZD users both concerning other addictions and sex, and also highlights the need for a stricter control of BZD use, ranging from prescriptions to sales.

Patterns of Polysubstance Use among Adults with Tranquilizer Misuse

Background: The misuse of benzodiazepine tranquilizers is prevalent and is associated with increased risk of overdose when combined with other substances. Yet, little is known about other substance use among those who misuse tranquilizers. Objectives: This study characterized subgroups of individuals with tranquilizer misuse, based on patterns of polysubstance use. Methods: Data were extracted from the 2015-2017 National Survey on Drug Use and Health; adults with past-month tranquilizer misuse were included (N = 1253). We utilized latent class analysis to identify patterns of polysubstance use in the previous month. Results: We identified three distinct latent classes, including the: (1) limited polysubstance use class (approximately 54.6% of the sample), (2) binge alcohol and cannabis use class (28.5% of the sample), and (3) opioid use class (16.9% of the sample). The binge alcohol and cannabis use class and the opioid use class were characterized by high probabilities of other substance misuse, including cocaine and prescription stimulants. Those in the binge alcohol and cannabis use class and the opioid use class reported more motives for tranquilizer misuse and higher rates of sexually transmitted infection, criminal involvement, and suicidal ideation. Those in the opioid use class also had greater psychological distress and higher rates of injection drug use. Conclusions: Nearly half of those with tranquilizer misuse in a general population sample were categorized into one of two high polysubstance use classes, and these two classes were associated with poorer functioning. Findings from these analyses underscore the need to reduce polysubstance use among those who misuse tranquilizers.

Systematic Review: Nonmedical Use of Prescription Stimulants: Risk Factors, Outcomes, and Risk Reduction Strategies

OBJECTIVE

To review all literature on the nonmedical use (NMU) and diversion of prescription stimulants to better understand the characteristics, risk factors, and outcomes of NMU and to review risk-reduction strategies.

METHOD

We systematically searched PubMed, PsycINFO, and SCOPUS from inception to May 2018 for studies containing empirical data about NMU and diversion of prescription stimulants. Additional references identified by the authors were also assessed for inclusion.

RESULTS

A total of 111 studies met inclusion criteria. NMU and diversion of stimulants are highly prevalent; self-reported rates among population samples range from 2.1% to 58.7% and from 0.7% to 80.0%, respectively. A variety of terms are used to describe NMU, and most studies have examined college students. Although most NMU is oral, non-oral NMU also occurs. The majority of NMU is associated with no, or minor, medical effects; however, adverse medical outcomes, including death, occur in some individuals, particularly when administered by non-oral routes. Although academic and occupational performance enhancement are the most commonly cited motivations, there is little evidence that academic performance is improved by NMU in individuals without attention-deficit/hyperactivity disorder.

CONCLUSION

NMU of stimulants is a significant public health problem, especially in college students, but variations in the terms used to describe NMU and inconsistencies in the available data limit a better understanding of this problem. Further research is needed to develop methods to detect NMU, identify individuals at greatest risk, study routes of administration, and devise educational and other interventions to help reduce occurrence of NMU. Colleges should consider including NMU in academic integrity policies.

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.

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.

Prevalence of nonmedical use and routes of administration for prescription stimulant medications among adults in a substance abuse treatment population

The aim was to examine prevalence of past 30-day prescription stimulant nonmedical use (NMU) by adults assessed for substance use problems and to better understand patterns of route of administration (ROA) and drug problem severity. Data were collected from a computer administered assessment of substance use problems completed by adults (age ≥ 18) using the Addiction Severity Index-Multimedia Version (ASI-MV^®) as part of the clinical intake process between January 2013 and March 2016. A cross-sectional observational study examined prevalence and prescription-adjusted prevalence of past 30-day NMU of prescription stimulants and compound-specific use by ROA (oral, snort, smoke, inject, other oral, and alternate ROA). Compounds of interest were amphetamine extended-release (ER), amphetamine immediate-release (IR), amphetamine mixed salts, methylphenidate ER, and methylphenidate IR. Of 198,411 respondents, 4,185 reported prescription stimulant NMU, prevalence ranged from 0.33% for methylphenidate IR to 1.61% for amphetamine mixed salts. Prescription-adjusted prevalence of NMU was highest for methylphenidate IR (0.51%) and lowest for amphetamine ER (0.28%). The most common ROA was oral, swallowed whole followed by snorting. There was a greater probability of nonmedical prescription stimulant use among respondents with higher drug severity ratings. Results suggest that one should not overlook the impact of prescription stimulant NMU in adults in treatment for substance use problems. NMU of prescription stimulants was associated with riskier routes of administration than reported for college student samples. A pattern of high-risk alternate ROA and increasing drug problem severity has important implications of substance use evaluation.

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.

Sources of Prescription Medication Misuse Among Young Adults in the United States: The Role of Educational Status

OBJECTIVE

This study examined prescription drug misuse (PDM), sources of PDM, and substance use disorder (SUD) symptoms as a function of educational status among US young adults based on a large nationally representative sample.

METHODS

Data from the 2009-2014 National Survey on Drug Use and Health came from a sample of 106,845 young adults aged 18-25 years. Respondents were categorized by educational status and PDM, sources of PDM, other substance use, and SUD symptoms, with analyses performed separately for prescription opioids, stimulants, and sedatives/tranquilizers.

RESULTS

Prescription opioid (past-year: 11.9%) and sedative/tranquilizer (past-year: 5.8%) misuse were most prevalent among young adults not attending college, especially among high school dropouts. In contrast, full-time college students and college graduates had the highest rates of prescription stimulant misuse (past-year: 4.3% and 3.9%, respectively). Obtaining prescription medications from friends/relatives for free was the most common source of PDM, especially among college students/graduates. Prescription drug misusers who obtained medications from theft/fake prescriptions, purchases, or multiple sources were more likely to report past-year SUDs and had the most severe overall risk profile of concurrent substance use and SUD. More than 70% of past-month prescription drug misusers who reported multiple sources for PDM had at least 1 past-year SUD.

CONCLUSIONS

Sources of PDM vary by educational status among US young adults, and the college environment is associated with sharing prescription medications. Clinicians can help assess an individual's risk for SUD by determining whether the individual engaged in PDM and the source of prescription medication the individual is misusing.

Prescriptions, nonmedical use, and emergency department visits involving prescription stimulants

OBJECTIVE

Little is known regarding the temporal trends in prescriptions, nonmedical use, and emergency department (ED) visits involving prescription stimulants in the United States. Our aim was to examine these 3 national trends involving dextroamphetamine-amphetamine and methylphenidate in adults and adolescents.

METHOD

Three national surveys conducted between 2006-2011 were used: National Disease and Therapeutic Index, a survey of office-based practices; National Survey on Drug Use and Health, a population survey of substance use; and Drug Abuse Warning Network, a survey of ED visits. Ordinary least squares regression was used to examine temporal changes over time and the associations between the 3 trends.

RESULTS

In adolescents, treatment visits involving dextroamphetamine-amphetamine and methylphenidate decreased over time; nonmedical dextroamphetamine-amphetamine use remained stable, while nonmedical methylphenidate use declined by 54.4% in 6 years. ED visits involving either medication remained stable. In adults, treatment visits involving dextroamphetamine-amphetamine remained unchanged, while nonmedical use went up by 67.1% and ED visits went up by 155.9%. These 3 trends involving methylphenidate remained unchanged. Across age groups, the major source for nonmedical use of both medications was a friend or relative; two-thirds of these friends and relatives had obtained the medication from a physician.

CONCLUSIONS

Trends in prescriptions for stimulants do not correspond to trends in reports of nonmedical use and ED visits. Increased nonmedical stimulant use may not be simply attributed to increased prescribing trends. Future studies should focus on deeper understanding of the proportion of, risk factors for, and motivations for drug diversions.