Use of item response theory and latent class analysis to link poly-substance use disorders with addiction severity, HIV risk, and quality of life among opioid-dependent patients in the Clinical Trials Network

Correlates of Stimulant Use among People Who Use Heroin Undergoing Treatment in Out-Patient Facilities in France, 2010-2020

Background: Polydrug use has been implicated in driving a "fourth wave" of the overdose crisis in North America, specifically through concurrent use of stimulants and opioids, especially fentanyl. In France, however, heroin has historically been and remains the easiest-to-access opioid, accounting for most drug treatment demand. Whether similar polydrug use is increasing in Western Europe remains understudied, despite severe health implications and potential inadequate public health responses.Methods: We take advantage of a nation-wide dataset containing information on all patients serviced in treatment centers in France from 2010 to 2020. We conduct Poisson regression to determine the main predictors of stimulant use among people who use heroin (PWUH) and opioids (PWUO) generally.Results: Heroin remains the primary opioid within drug treatment in France. A decreasing number of out-patients seeking treatment for heroin use has been accompanied by an increasing trend of stimulant use over time, most commonly with powder cocaine. Our results suggest a significant increase of crack cocaine use among the most vulnerable PWUH. Concurrent use of stimulants among PWUH was positively associated with use of alcohol, cannabis, unprescribed psychotropics and hallucinogens, and negatively with tobacco. Similar results were found for all in-treatment PWUO.Conclusions: Our results uncover heterogeneity in the profiles of PWUH that should be fully acknowledged to ensure better efficiency in substance use clinical practices and policy, while simultaneously drawing attention to trends in concurrent opioid-stimulant use outside North America. We advocate for an extension of the generalized risk framework and its implementation in prevention programs.

Substance Use and Mental Health Screening Within an Emergency Department-Based HIV Screening Program: Outcomes From 1 Year of Implementation

INTRODUCTION

The emergency department (ED) may be an optimal setting to screen for substance use disorders (SUDs) and co-occurring psychiatric disorders (CODs). We report on the frequency of problematic substance use and comorbid elevated mental health symptoms detected during a 1-year implementation period of an ED-based SUD/COD screening approach within an established ED HIV screening program.

METHODS

Patients (N = 1,924) were approached by dedicated HIV screening staff in an urban, Midwestern ED. Patients first completed measures assessing problematic alcohol (Alcohol Use Disorder Identification Test-Concise [AUDIT-C]) and substance use across 10 categories of substances (National Institute on Drug Abuse-Modified Alcohol, Smoking, and Substance Involvement Screening Test [NIDA-Modified ASSIST]). Patients with positive alcohol and/or substance use screens completed measures assessing symptoms of depression (Patient Health Questionnaire-9 [PHQ-9]), anxiety (Generalized Anxiety Disorder-7 [GAD-7]), and post-traumatic stress disorder (PTSD) (PTSD Checklist-Civilian [PCL-C]).

RESULTS

Patients were predominantly male (60.3%) with a mean age of 38.1 years (SD = 13.0); most identified as White (50.8%) or Black (44.8%). A majority (58.5%) had a positive screen for problematic alcohol and/or other substance use. Of those with a positive substance use screen (n = 1,126), 47.0% had a positive screen on one or more of the mental health measures with 32.1% endorsing elevated depressive symptoms, 29.6% endorsing elevated PTSD-related symptoms, and 28.5% endorsing elevated anxiety symptoms.

CONCLUSIONS

Among those receiving ED HIV screening, a majority endorsed problematic alcohol and/or other substance use and co-occurring elevated mental health symptoms. Substance use and mental health screening programs that can be integrated within other ED preventive services may enhance the identification of individuals in need of further assessment, referral, or linkage to substance use treatment services.

Patterns of polysubstance use and clinical comorbidity among persons seeking substance use treatment: An observational study

INTRODUCTION

Polysubstance use is common among individuals seeking treatment for substance use disorders (SUD). However, we know less about patterns and correlates of polysubstance use among treatment-seeking populations. The current study aimed to identify latent patterns of polysubstance use and associated risk factors in persons entering SUD treatment.

METHODS

Patients (N = 28,526) being admitted for substance use treatment reported on their use of thirteen substances (e.g., alcohol, cannabis, cocaine, amphetamines, methamphetamines, other stimulants, heroin, other opioids, benzodiazepines, inhalants, synthetics, hallucinogens, and club drugs) in the month before treatment and prior to the month before treatment. Latent class analysis (LCA) determined the relationship between class membership and gender, age, employment status, unstable housing, self-harm, overdose, past treatment, depression, generalized anxiety disorder, and/or post-traumatic stress disorder (PTSD).

RESULTS

Identified classes included: 1) Alcohol primary, 2) Moderate probability of past-month alcohol, cannabis, and/or opioid use; 3) Alcohol primary, Lifetime cannabis and cocaine use; 4) Opioid primary, Lifetime use of alcohol, cannabis, hallucinogens, club drugs, amphetamines, and cocaine; 5) Moderate probability of past-month alcohol, cannabis, and/or opioid use, Lifetime use of various substances; 6) Alcohol and cannabis primary, Lifetime use of various substances; and 7) High past-month polysubstance use. Individuals who engaged in past-month polysubstance use attended to face elevated risk of screening positive for recent unstable housing, unemployment, depression, anxiety, PTSD, self-harm, and overdose.

CONCLUSIONS

Current polysubstance use is associated with significant clinical complexity. Tailored treatments that reduce harms resulting from polysubstance use and related psychiatric comorbidity may improve treatment outcomes in this population.

Adolescent substance use and high school noncompletion: exploring the nature of the relationship using a discordant twin design

BACKGROUND AND AIMS

Previous studies have demonstrated associations between substance use and reduced educational attainment; however, many were unable to account for potential confounding factors like genetics and the rearing environment. In the few studies that controlled for these factors, the substances assessed were limited to alcohol, cannabis, and tobacco. To address these limitations, we examined the relationship between adolescent use of seven kinds of substances, the number of additional substances used, and high school noncompletion within a large sample of Australian twins.

DESIGN

A series of two-level generalized mixed effects logistic regressions were conducted to examine associations between adolescent substance use and high school noncompletion.

SETTING

Australia.

PARTICIPANTS

A total of 9579 adult Australian twins from two cohorts of the Australian Twin Registry.

MEASUREMENTS

Assessments of high school completion, childhood major depression, conduct disorder symptoms, substance use initiation, demographics, and parental educational attainment using the Australian version of the Semi-Structured Assessment for the Genetics of Alcoholism.

FINDINGS

There were unique within-twin-pair effects of use of sedatives (odds ratio [OR] = 22.39 [95% confidence interval (CI) = 1.18-423.48]) and inhalants/solvents (OR = 10.46 [95% CI = 1.30-84.16]) on high school noncompletion. The number of substances used in adolescence was strongly associated with high school noncompletion across all discordant twin models (ORs from 1.50-2.32, Ps < 0.03).

CONCLUSIONS

In Australia, adolescent substance use appears to be associated with early school dropout, with the effects of any given substance largely because of the confounding factors of parental education, childhood conduct disorder symptoms, and use of other substances. Sedatives and inhalants/solvents have effects on high school noncompletion that cannot be explained by polysubstance use or familial factors.

Problematic Gambling Behavior in a Sample with Substance Use Disorder: The Role of Attachment Style and Alexithymia

Gambling disorder is a high comorbid disorder in substance abusers which conjunct appearance is related to worse symptomatology and evolution. Nevertheless, the research on the risk factors that may explain this comorbidity is scarce. We build of the self-regulation theory of attachment and addiction to examine if insecure attachment is related to gambling comorbidity in substance abuse disorder and the mediating role of alexithymia in this process. A cross-sectional study was carried out with 369 clinical patients with substance use disorder of which 69 presented comorbid gambling disorder diagnosed with the DSM-5 criteria. Results showed that insecure attachment was more prevalent in the group with comorbid gambling. In this group, the alexithymia levels were also higher and mediated the relationship in between attachment and gambling disorder comorbidity even controlling for several sociodemographic variables. This research indicates that insecure attachment enhances the risk of gambling comorbidity on substance abusers due to the detrimental effect on the self-regulation of emotion. Thus, interventions directed to increase the identification, expression and awareness of emotions might help to reduce comorbidity of gambling of substance use disorders.

Latent Classes of Polysubstance Use and Associations with HIV Risk and Structural Vulnerabilities among Cisgender Women Who Engage in Street-Based Transactional Sex in Baltimore City

We describe patterns of polysubstance use and associations with HIV risk-related behaviors among women engaged in street-based transactional sex, an understudied yet important population and area of research. This sample was restricted to cisgender women who reported drug use (n = 244) in the baseline of the longitudinal SAPPHIRE cohort study. Latent class analysis (LCA) was conducted using drug use measures (route of administration (injection/non-injection); type of drug (specific opioids, stimulants)) and selection based on fit statistics and qualitative interpretation of the classes. Polysubstance use was prevalent (89% ≥ 2), and 68% had injected drugs in the past 3 months. A three-class solution was selected: Class 1 ("heroin/cocaine use", 48.4% of sample), Class 2 ("poly-opioid use", 21.3%), and Class 3 ("poly-route, polysubstance use", 30.3%). Class 3 was significantly younger, and Class 2 was disproportionately non-White. Women reported high levels of housing (63%) and food (55%) insecurity, condomless sex with clients (40%), and client-perpetrated violence (35%), with no significant differences by class. Obtaining syringes from syringe services programs differed significantly by class, despite injection behaviors in all classes. Tailored HIV and overdose prevention programming that considers drug use patterns would strengthen their impact.

Profiles of lifetime substance use are differentiated by substance of choice, affective motivations for use, and childhood maltreatment

To develop personalized interventions and improve outcomes in substance-using populations, research is needed on the heterogeneity in substance use patterns and motivations that exists among adult substance users. This study took a person-centered approach to identify profiles of lifetime substance use and discern the psychosocial differences among them. To survey a spectrum of drug use severity, 1106 adults (43.4% women) were recruited from forensic and community samples. Participants reported on the frequency of lifetime substance use across multiple drug categories (sedatives, stimulants, marijuana, heroin, hallucinogens, misuse of prescription drugs) and alcohol use. Latent profile analysis was used to identify distinct profiles of substance use that were then compared on potential risk and maintenance factors for substance use. Four profiles of lifetime substance use emerged that diverged on severity of use and degree of mono vs. polysubstance use (Recreational Marijuana Use, Heavy Multidrug Intoxication, Heavy Marijuana Use, and Heavy Opioid and Polysubstance Use). The profiles differed on affective motivations for substance use (e.g., using to cope vs. using to seek a thrill), age of use onset, drug-related functional impairment, and experiences of childhood maltreatment. Cognitive functioning did not differentiate the heavy substance use profiles. Results provide compelling initial evidence that lifetime patterns of use can be used to identify groups of substance users with distinct risk and maintenance factors. Results highlight affective motivations for substance use and maltreatment history as potential treatment targets and underscore the importance of studying polysubstance use in the context of the opioid epidemic.

Characterizing profiles of polysubstance use among high school students in Baltimore, Maryland: A latent class analysis

BACKGROUND

Adolescent drug use has long term health consequences, like substance use disorders and psychiatric illnesses. Proximal health risks, especially for overdose, are amplified when multiple substances are combined. Existing literature on polysubstance use among adolescents has largely focused on alcohol, tobacco, and marijuana, but has largely excluded other drugs like opioids. Understanding how adolescents combine illicit drugs is essential for intervening to prevent poor health outcomes.

METHODS

We aimed to explore patterns of lifetime polysubstance use among adolescents in Baltimore City. We used data on 9th-12th graders recruited to participate in the 2017 local Baltimore Youth Risk Behavior Survey who reported any lifetime drug use (n = 387; 60 % female, 77 % non-Hispanic Black). We then conducted a latent class analysis using 10 indicators of lifetime drug and alcohol use. After selecting the class model, we tested for associations between the class profiles and race, sex, school grade, and lifetime injection drug use.

RESULTS

We identified three profiles of lifetime polysubstance use in our sample: alcohol and marijuana (68.6 % of sample), polysubstance (22.0 %), and alcohol/pain medication/inhalant use (9.4 %). Members of the polysubstance use class were more likely to be male and to report injection drug use.

CONCLUSIONS

Understanding broader patterns of drug use beyond alcohol, tobacco and marijuana among adolescents is a crucial step towards preventing adverse drug and health-related outcomes later in life. More research is needed to characterize the full health impact of youth polysubstance use patterns and related risk behaviors like injection drug use.

Adolescent Anabolic-Androgenic Steroid Use in Association with Other Drug Use, Injection Drug Use, and Team Sport Participation

Introduction

The majority of epidemiologic research on adolescent non-medical anabolic-androgenic steroid (AAS) use was conducted in the 1990s and early 2000s, indicating a need to update evidence for the modern era. We aim to understand the prevalence of AAS use among US adolescents and assess associations between AAS use, sports participation, other drug use, and injection drug use (IDU).

Methods

Using data from the 2017 National Youth Risk Behavior Survey, we estimated the prevalence of AAS use and tested for associations between AAS use, sports participation, and drug use, overall and by sex.

Results

The prevalence of AAS use was 2.98%. The prevalence among boys (3.46%) was higher than among girls (2.41%). AAS use was high among youth with lifetime heroin use (64.41%) and IDU (64.42%). There was no association between AAS and team sport participation (p=0.61).

Conclusions

Our results indicate that adolescent AAS use is an aspect of polysubstance use rather than a substance used solely for performance enhancement in sports. Research with adolescents should be mindful of the overlap of heroin and AAS use among youth with IDU.

Utilizing social media to explore overdose and HIV/HCV risk behaviors among current opioid misusers

INTRODUCTION

Opioid misuse has evolved into an American health crisis over the past decade, becoming a public health epidemic. Measures need to be taken to prevent overdoses by opioid misuse as well as prevent the transition into injection drug use, a high risk factor for contracting HIV/HCV. This study utilized social media to survey individuals currently misusing opioids to identify groups of individuals with different risk and use patterns.

METHODS

We recruited participants for our online survey from Reddit. Five risk behaviors were used to characterize overdose and HIV/HCV risk groups. Gender, age, and socioeconomic status were also included in the analyses, as well as items outlining social media use surrounding opioids.

RESULTS

Two groups of participants were characterized by high likelihoods of different combinations of risky behaviors: (1) Overdose Risk Group and (2) Sexual Risk Group. Those in the Overdose Risk Group were more likely to be younger in age and female, and this group was more likely to desire or be ready for treatment relative to the lowest risk group. Those in the Sexual Risk Group were more likely to be of a minority race/ethnicity, to desire or be ready for treatment, and to post more often on Reddit about opioid use.

DISCUSSION

The results of this study illustrate patterns of opioid use and risk behaviors to inform tailored outreach and treatment efforts for groups of opioid misusers and suggests the potential for utilizing social media as a tool to engage these individuals into treatment and recovery activities.

A Resampling Based Grid Search Method to Improve Reliability and Robustness of Mixture-Item Response Theory Models of Multimorbid High-Risk Patients

There are many statistics available to the applied statistician for assessing model fit and even more methods for assessing internal and external validity. We detail a useful approach using a grid search technique that balances the internal model consistency with generalizability and can be used with models that naturally lend themselves to multiple assessment techniques. Our method relies on resampling and a simple grid search method over 3 commonly used statistics that are simple to calculate. We apply this method in a latent traits framework using a mixture Item Response Theory (MIXIRT) model of common chronic health conditions. Model fit is assessed using Akaike's Information Criteria (AIC), latent class similarity is measured with the Variance of Information (VI), and the consistency of condition complexity and prevalence across latent classes is compared using Kendall's τ rank order statistic. From two patient cohorts at high risk for hospitalization in 2014 and 2018, we generated 19 MIXIRT models (allowing 2-20 latent classes) on 21 common comorbid conditions identified via healthcare encounter diagnosis codes. We ran these models on 100 bootstrap samples of size 10% for each cohort. Among the resulting models, combined AIC and VI statistics identified 5-7 latent classes, but the rank order correlation of condition complexity revealed that only the 5 class solutions had consistent condition complexity. The 5 class solutions were combined to produce a single parsimonious MIXIRT solution that balanced clinical significance with model fit, cluster similarity, and consistency of condition complexity.

A latent class approach to identify multi-risk profiles associated with phylogenetic clustering of recent hepatitis C virus infection in Australia and New Zealand from 2004 to 2015

INTRODUCTION

Over the last two decades, the incidence of hepatitis C virus (HCV) co-infection among men who have sex with men (MSM) living with HIV began increasing in post-industrialized countries. Little is known about transmission of acute or recent HCV, in particular among MSM living with HIV co-infection, which creates uncertainty about potential for reinfection after HCV treatment. Using phylogenetic methods, clinical, epidemiological and molecular data can be combined to better understand transmission patterns. These insights may help identify strategies to reduce reinfection risk, enhancing effectiveness of HCV treatment as prevention strategies. The aim of this study was to identify multi-risk profiles and factors associated with phylogenetic pairs and clusters among people with recent HCV infection.

METHODS

Data and specimens from five studies of recent HCV in Australia and New Zealand (2004 to 2015) were used. HCV Core-E2 sequences were used to infer maximum likelihood trees. Clusters were identified using 90% bootstrap and 5% genetic distance threshold. Multivariate logistic regression and latent class analyses were performed.

RESULTS

Among 237 participants with Core-E2 sequences, 47% were in a pair/cluster. Among HIV/HCV co-infected participants, 60% (74/123) were in a pair/cluster, compared to 30% (34/114) with HCV mono-infection (p < 0.001). HIV/HCV co-infection (vs. HCV mono-infection; adjusted odds ratio (AOR), 2.37, 95% confidence interval (CI), 1.45, 5.15) was independently associated with phylogenetic clustering. Latent class analysis identified three distinct risk profiles: (1) people who inject drugs, (2) HIV-positive gay and bisexual men (GBM) with low probability of injecting drug use (IDU) and (3) GBM with IDU & sexual risk behaviour. Class 2 (vs. Class 1, AOR 3.40; 95% CI, 1.52, 7.60), was independently associated with phylogenetic clustering. Many clusters displayed homogeneous characteristics, such as containing individuals exclusively from one city, individuals all with HIV/HCV co-infection or individuals sharing the same route of acquisition of HCV.

CONCLUSIONS

Clusters containing individuals with specific characteristics suggest that HCV transmission occurs through discrete networks, particularly among HIV/HCV co-infected individuals. The greater proportion of clustering found among HIV/HCV co-infected participants highlights the need to provide broad direct-acting antiviral access encouraging rapid uptake in this population and ongoing monitoring of the phylogeny.

Prevalence and patterns of opioid misuse and opioid use disorder among primary care patients who use tobacco

BACKGROUND

Current data suggest that opioid misuse or opioid use disorder (OUD) may be over represented among tobacco users. However, this association remains understudied in primary care settings. A better understanding of the extent of heterogeneity in opioid misuse among primary care patients who use tobacco may have implications for improved primary care-based screening, prevention, and intervention approaches.

METHODS

Data were derived from a sample of 2000 adult (aged ≥18) primary care patients across 5 distinct clinics. Among past-year tobacco users (n = 882), we assessed the prevalence of opioid misuse and OUD by sociodemographic characteristics and past-year polysubstance use. Latent class analysis (LCA) was used to identify heterogeneous subgroups of tobacco users according to past-year polysubstance use patterns. Multinomial logistic regression was used to examine variables associated with LCA-defined class membership.

RESULTS

Past-year tobacco use was reported by >84% of participants who reported past-year opioid misuse or OUD. Among those reporting past-year tobacco use, the prevalence of past-year opioid misuse and OUD was 14.0% and 9.5%, respectively. The prevalence of opioid misuse or OUD was highest among tobacco users who were male or unemployed. Three LCA-defined classes among tobacco users were identified including a tobacco-minimal drug use group (78.0%), a tobacco-cannabis use group (10.1%), and a tobacco-opioid/polydrug use group (11.9%). Class membership differed by sociodemographic characteristics.

CONCLUSIONS

Results from this study support the benefit of more comprehensive assessment of and/or monitoring for opioid misuse among primary care patients who use tobacco, particularly for those who are male, unemployed, or polydrug users.

Using item response theory with health system data to identify latent groups of patients with multiple health conditions

A critical step toward tailoring effective interventions for heterogeneous and medically complex patients is to identify clinically meaningful subgroups on the basis of their comorbid conditions. We applied Item Response Theory (IRT), a potentially useful tool to identify clinically meaningful subgroups, to characterize phenotypes within a cohort of high-risk patients. This was a retrospective cohort study using 68,400 high-risk Veteran’s Health Administration (VHA) patients. Thirty-one physical and mental health diagnosis indicators based on ICD-9 codes from patients’ inpatient, outpatient VHA and VA-paid community care claims. Results revealed 6 distinct subgroups of high-risk patients were identified: substance use, complex mental health, complex diabetes, liver disease, cancer with cardiovascular disease, and cancer with mental health. Multinomial analyses showed that subgroups significantly differed on demographic and utilization variables which underscored the uniqueness of the groups. Using IRT models with clinical diagnoses from electronic health records permitted identification of diagnostic constellations among otherwise undifferentiated high-risk patients. Recognizing distinct patient profiles provides a framework from which insights into medical complexity of high-risk patients can be explored and effective interventions can be tailored.

An item response theory based integrated model of headache, nausea, photophobia, and phonophobia in migraine patients

This study developed an integrated model of severity scores of migraine headache and the incidence of nausea, photophobia, and phonophobia to predict the natural time course of migraine symptoms, which are likely to occur by a common disease progression mechanism. Data were acquired from two phase 3 clinical trials conducted during the development of eletriptan. Only the placebo arm was used for analysis. A conventional proportional odds model was compared with an item response theory (IRT) based approach. Results suggested that the IRT based approach led to a better model fit, successfully revealing the difference in relief rates among different symptoms, which was the fastest in phonophobia and the slowest in headache. Simulation with the developed model suggested that using headache scores at 4 h post-dose attained greatest statistical power, yielding sample size of 100 per arm given drug effect of 40%, as compared to that of 200 per arm when 2 h post-dose scores were used as in the original eletriptan protocol. This work demonstrated the usefulness of an IRT based model as applied to analyzing multidimensional migraine symptoms and designing clinical trials. Our model can be similarly applied to analyzing other multiple endpoints sharing a common underlying mechanism.

Clinical characteristics of poly-drug abuse among heroin dependents and association with other psychopathology in compulsory isolation treatment settings in China

OBJECTIVE

To investigate clinical characteristics and associations of polydrug abuse among heroin-dependent patients in compulsory isolation settings in China.

METHODS

Structured interviews were conducted in 882 heroin-dependent patients in two compulsory isolation settings in Changsha, China. Descriptive statistics were employed to report prevalence and general information of polydrug abuse among the participants. Bivariate associations were examined between polydrug abuse and variables regarding demographics, heroin use profile and psychopathology. Multivariate logistic regressions were conducted to determine independent factors associated with polydrug abuse.

RESULTS

Of all the participants, 40.6% reported abuse of/dependence on at least one other type of drug/alcohol than heroin/opioids during the month preceding admission, with benzodiazepines and alcohol being the most common type of drugs abused apart from heroin. Antisocial and depressive personality disorders, as well as more severe heroin use patterns, including younger age at initiate use and larger amount used per day, were found to be independently associated with polydrug abuse.

CONCLUSIONS

The prevalence of polydrug abuse and its associated severe heroin use patterns and personality disorders suggests an urgent need of promoting treatment policies and strategies for heroin patients in China to address these issues.

Prevalence, patterns, and correlates of multiple substance use disorders among adult primary care patients

BACKGROUND

Addressing multiple substance use disorders (SUDs) in primary care-based screening and intervention may improve SUD treatment access, engagement, and outcomes. To inform such efforts, research is needed on the prevalence and patterns of multiple SUDs among primary care patients.

METHODS

Data were analyzed from a sample of 2000 adult (aged ≥ 18) primary care patients recruited for a multisite National Drug Abuse Treatment Clinical Trials Network (CTN) study (CTN-0059). Past-year DSM-5 SUDs (tobacco, alcohol, and drug) were assessed by the modified Composite International Diagnostic Interview. Prevalence and correlates of multiple versus single SUDs were examined. Latent class analysis (LCA) was used to explore patterns of multiple SUDs.

RESULTS

Multiple SUDs were found among the majority of participants with SUD for alcohol, cannabis, prescription opioids, cocaine, and heroin. Participants who were male, ages 26-34, less educated, and unemployed had increased odds of multiple SUDs compared to one SUD. Having multiple SUDs was associated with greater severity of tobacco or alcohol use disorder. LCA of the sample identified three classes: class 1 (83.7%) exhibited low prevalence of all SUDs; class 2 (12.0%) had high-moderate prevalence of SUDs for tobacco, alcohol, and cannabis; class 3 (4.3%) showed high prevalence of SUD for tobacco, opioids, and cocaine. LCA-defined classes were distinguished by sex, age, race, education, and employment status.

CONCLUSIONS

Findings suggest that primary care physicians should be aware of multiple SUDs when planning treatment, especially among adults who are male, younger, less educated, or unemployed. Interventions that target multiple SUDs warrant future investigation.

Drug use and phylogenetic clustering of hepatitis C virus infection among people who use drugs in Vancouver, Canada: A latent class analysis approach

This study estimated latent classes (ie, unobserved subgroups in a population) of people who use drugs in Vancouver, Canada, and examined how these classes relate to phylogenetic clustering of hepatitis C virus (HCV) infection. HCV antibody-positive people who use drugs from two cohorts in Vancouver, Canada (1996-2012), with a Core-E2 sequence were included. Time-stamped phylogenetic trees were inferred, and phylogenetic clustering was determined by time to most common recent ancestor. Latent classes were estimated, and the association with the phylogenetic clustering outcome was assessed using an inclusive classify/analyse approach. Among 699 HCV RNA-positive participants (26% female, 24% HIV+), recent drug use included injecting cocaine (80%), injecting heroin (70%), injecting cocaine/heroin (ie, speedball, 38%) and crack cocaine smoking (28%). Latent class analysis identified four distinct subgroups of drug use typologies: (i) cocaine injecting, (ii) opioid and cocaine injecting, (iii) crack cocaine smoking and (iv) heroin injecting and currently receiving opioid substitution therapy. After adjusting for age and HIV infection, compared to the group defined by heroin injecting and currently receiving opioid substitution therapy, the odds of phylogenetic cluster membership was greater in the cocaine injecting group (adjusted OR [aOR]: 3.06; 95% CI: 1.73, 5.42) and lower in the crack cocaine smoking group (aOR: 0.06; 95% CI: 0.01, 0.48). Combining latent class and phylogenetic clustering analyses provides novel insights into the complex dynamics of HCV transmission. Incorporating differing risk profiles associated with drug use may provide opportunities to further optimize and target HCV treatment and prevention strategies.

Alcohol use disorders are associated with increased HIV risk behaviors in cocaine-dependent methadone patients

People who inject drugs (PWID) are at increased risk of HIV infection. Although methadone maintenance therapy can help lower this risk, many methadone patients continue to engage in HIV risk behaviors, especially patients who use cocaine and alcohol. The purpose of the current study was to investigate relations between alcohol use disorders and HIV risk behavior in 239 cocaine-dependent methadone patients participating in a randomized controlled trial of a behavioral intervention to promote cocaine abstinence. Past 3-month HIV Risk-taking Behavior Scale (HRBS) scores were compared between cocaine-dependent methadone patients who met DSM-IV-TR diagnostic criteria for alcohol abuse or dependence and those who did not meet these criteria. No significant differences in HRBS drug subscale scores were observed between participants with and without alcohol use disorders, indicating risky drug use was similar between groups. However, alcohol use disorder was significantly associated with HRBS sex subscale scores (t=2.59, p=0.01), indicating participants with alcohol use disorders were more likely to engage in risky sexual behavior. Item-level analyses of the sex-related HRBS questions showed participants with alcohol use disorders were significantly more likely than participants without alcohol use disorders to have unprotected sex, engage in transactional (paid) sex, and have anal sex. Interventions are needed to reduce risky sexual behavior and attenuate the spread of HIV in this high-risk population.

Association between severity of illicit drug dependence and quality of life in a psychosocial care center in BRAZIL: cross-sectional study

Background

Quality of life must be one of the main purposes for the treatment of drug users, requiring a better understanding of the association between the quality of life and the severity of dependency. This study aimed to investigate the correlation between severity of substance use in various areas of human functioning and quality of life of illicit drug users in a psychosocial care center for alcohol and drugs.

Methods

This cross-sectional study included 60 participants – illicit drug users – treated at a psychosocial care center for alcohol and drugs. Participants were evaluated with the short version of World Health Organization Quality of Life (WHOQOL-Bref) instrument to measure the quality of life, the 6th version of Addiction Severity Index (ASI-6) to assess the severity of dependence in several areas and the Mini International Neuropsychiatric Interview (MINI) to identify the presence of psychiatric disorders. Pearson and Spearman correlation tests and linear regression were applied to verify the association between the severity of dependence and the quality of life, and Student’s t-test to compare the mean quality of life between individuals with and without psychiatric comorbidities.

Results

Negative correlation was found between the severity of dependence on the drugs dimensions: alcohol, psychiatric, medical, legal, family/social support and family/social problems of ASI-6, and the quality of life domains measured by the WHOQOL-Bref. The evidence was strongest in the psychiatric and medical dimensions. There was a significant difference in the quality of life mean among participants presenting or not presenting psychiatric comorbidities, for the psychological domain in anxiety disorders, and for the physical and psychological domains in mood disorders.

Conclusion

The quality of life decreased as the severity of dependence increased, with different results in the various areas of the participant’s life. This result emphasizes the need for training the professional team which works in the substance use disorders area for more comprehensive diagnostic evaluations and more appropriate therapeutic interventions for each area. The associations were more evident in the medical and psychiatric fields, indicating the need for greater attention to be paid in relation to medical and psychiatric comorbidities.

Electronic supplementary material

The online version of this article (10.1186/s12955-017-0795-5) contains supplementary material, which is available to authorized users.

Social Network Strategies to Address HIV Prevention and Treatment Continuum of Care Among At-risk and HIV-infected Substance Users: A Systematic Scoping Review

Social network analysis (SNA) and social network-based interventions (SNI) are important analytical tools harnessing peer and family influences critical for HIV prevention and treatment among substance users. While SNA is an effective way to measure social network influences, SNI directly or indirectly involves network members in interventions. Even though these methods have been applied in heterogeneous ways, leading to extensive evidence-based practices, systematic reviews are however, lacking. We searched five bibliographic databases and identified 58 studies involving HIV in substance users that had utilized SNA or SNI as part of their methodology. SNA was used to measure network variables as inputs in statistical/mathematical models in 64 % of studies and only 22 % of studies used SNI. Most studies focused on HIV prevention and few addressed diagnosis (k = 4), care linkage and retention (k = 5), ART adherence (k = 2), and viral suppression (k = 1). This systematic review highlights both the advantages and disadvantages of social network approaches for HIV prevention and treatment and gaps in its use for HIV care continuum.

Latent classes of polydrug and polyroute use and associations with human immunodeficiency virus risk behaviours and overdose among people who inject drugs in Tijuana, Baja California, Mexico

INTRODUCTION AND AIMS

Patterns of polydrug use among people who inject drugs (PWID) may be differentially associated with overdose and unique human immunodeficiency virus (HIV) risk factors. Subgroups of PWID in Tijuana, Mexico, were identified based on substances used, route of administration, frequency of use and co-injection indicators.

DESIGN AND METHODS

Participants were PWID residing in Tijuana age ≥18 years sampled from 2011 to 2012 who reported injecting an illicit substance in the past month (n = 735). Latent class analysis identified discrete classes of polydrug use characterised by 11 indicators of past 6 months substance use. Multinomial logistic regression examined class membership association with HIV risk behaviours, overdose and other covariates using an automated three-step procedure in mplus to account for classification error.

RESULTS

Participants were classified into five subgroups. Two polydrug and polyroute classes were defined by use of multiple substances through several routes of administration and were primarily distinguished from each other by cocaine use (class 1: 5%) or no cocaine use (class 2: 29%). The other classes consisted primarily of injectors: cocaine, methamphetamine and heroin injection (class 3: 4%); methamphetamine and heroin injection (class 4: 10%); and heroin injection (class 5: 52%). Compared with the heroin-only injection class, memberships in the two polydrug and polyroute use classes were independently associated with both HIV injection and sexual risk behaviours.

DISCUSSION AND CONCLUSIONS

Substance use patterns among PWID in Tijuana are highly heterogeneous, and polydrug and polyroute users are a high-risk subgroup who may require more tailored prevention and treatment interventions. [Meacham MC, Roesch SC, Strathdee SA, Lindsay S, Gonzalez-Zuniga P, Gaines TL. Latent classes of polydrug and polyroute use and associations with human immunodeficiency virus risk behaviours and overdose among people who inject drugs in Tijuana, Baja California, Mexico. Drug Alcohol Rev 2018;37:128-136].

Patterns of drug use, risky behavior, and health status among persons who inject drugs living in San Diego, California: a latent class analysis

BACKGROUND

Among persons who inject drugs (PWID), polydrug use (the practice of mixing multiple drugs/alcohol sequentially or simultaneously) increases risk for HIV transmission and unintentional overdose deaths. Research has shown local drug markets influence drug use practices. However, little is known about the impact of drug mixing in markets dominated by black tar heroin and methamphetamine, such as the western United States.

METHODS

Data were collected through an ongoing longitudinal study examining drug use, risk behavior, and health status among PWID. Latent class analysis (LCA) was used to identify patterns of substance use (heroin, methamphetamine, prescription drugs, alcohol, and marijuana) via multiple administration routes (injecting, smoking, and swallowing). Logistic regression was used to identify behaviors and health indicators associated with drug use class.

RESULTS

The sample included 511 mostly white (51.5%) males (73.8%), with mean age of 43.5 years. Two distinct classes of drug users predominated: methamphetamine by multiple routes (51%) and heroin by injection (49%). In multivariable logistic regression, class membership was associated with age, race, and housing status. PWID who were HIV-seropositive and reported prior sexually transmitted infections had increased odds of belonging to the methamphetamine class. Those who were HCV positive and reported previous opioid overdose had an increased odds of being in the primarily heroin injection class (all P-values < .05).

CONCLUSION

Risk behaviors and health outcomes differed between PWID who primarily inject heroin vs. those who use methamphetamine. The findings suggest that in a region where PWID mainly use black tar heroin or methamphetamine, interventions tailored to sub-populations of PWID could improve effectiveness.

Comorbid substance use disorders with other Axis I and II mental disorders among treatment-seeking Asian Americans, Native Hawaiians/Pacific Islanders, and mixed-race people

Little is known about behavioral healthcare needs of Asian Americans (AAs), Native Hawaiians/Pacific Islanders (NHs/PIs), and mixed-race people (MRs)-the fastest growing segments of the U.S. population. We examined substance use disorder (SUD) prevalences and comorbidities among AAs, NHs/PIs, and MRs (N = 4572) in a behavioral health electronic health record database. DSM-IV diagnoses among patients aged 1-90 years who accessed behavioral healthcare from 11 sites were systematically captured: SUD, anxiety, mood, personality, adjustment, childhood-onset, cognitive/dementia, dissociative, eating, factitious, impulse-control, psychotic/schizophrenic, sleep, and somatoform diagnoses. Of all patients, 15.0% had a SUD. Mood (60%), anxiety (31.2%), adjustment (30.9%), and disruptive (attention deficit-hyperactivity, conduct, oppositional defiant, disruptive behavior diagnosis, 22.7%) diagnoses were more common than others (psychotic 14.2%, personality 13.3%, other childhood-onset 11.4%, impulse-control 6.6%, cognitive 2.8%, eating 2.2%, somatoform 2.1%). Less than 1% of children aged <12 years had SUD. Cannabis diagnosis was the primary SUD affecting adolescents aged 12-17. MRs aged 35-49 years had the highest prevalence of cocaine diagnosis. Controlling for age at first visit, sex, treatment setting, length of treatment, and number of comorbid diagnoses, NHs/PIs and MRs were about two times more likely than AAs to have ≥ 2 SUDs. Regardless of race/ethnicity, personality diagnosis was comorbid with SUD. NHs/PIs with a mood diagnosis had elevated odds of having SUD. Findings present the most comprehensive patterns of mental diagnoses available for treatment-seeking AAs, NHs/PIs, and MRs in the real-world medical setting. In-depth research is needed to elucidate intraracial and interracial differences in treatment needs.

Defining 10-2 visual field progression criteria: exploratory and confirmatory factor analysis using pointwise linear regression

PURPOSE

To test different visual field progression criteria using trend analysis in a glaucoma population followed with long sequences of 10-2 tests as a first attempt to understand and document rates of progression in the central field.

DESIGN

Retrospective cohort study.

PARTICIPANTS

We included 146 eyes of 146 patients with established glaucoma.

METHODS

Pointwise linear regression analysis using the methods of ordinary least squares was performed on the 68 test locations of the 10-2 visual field sequences. Threshold sensitivities at each test location were plotted as the dependent variable against follow-up time as the independent variable. Statistically significant progression or improvement of a visual field test point was defined if its regression slope measured ≤-1.0 dB/year or ≥+1.0 dB/year, respectively, at P<0.01. We explored sets of criteria to define visual field progression, generating a hypothetical sensitivity (progression), specificity (improvement), and progression-to-improvement ratio (PIR) for each criterion. The criterion with the highest PIR was deemed the one with best performance. Latent class analysis (LCA) was used to determine visual field sectors with highest inter-correlation.

MAIN OUTCOME MEASURES

The performance of different visual field progression criteria to detect fast rates of mean deviation (MD) change.

RESULTS

Median baseline 10-2 MD value was -12.0 dB (interquartile range [IQR], -6.7 to -17.8 dB), and the median rate of 10-2 MD change over time was -0.38 dB/year (IQR, -0.07 to -0.77 dB/year). The highest PIR was obtained with the progression criterion requiring at least 3 test points located in the same LCA-derived 10-2 visual field sector progressing faster than -1.0 dB/year at P<0.01. This criterion was further validated for content and convergence.

CONCLUSIONS

This is the first study to investigate progression criteria for 10-2 visual fields using rates of change and to test their performance and validity. These findings may be useful to improve the monitoring of patients with glaucoma at different levels of functional loss and to develop new perimetric algorithms that scrutinize specific visual field locations for a more accurate detection of progression.

The national drug abuse treatment clinical trials network data share project: website design, usage, challenges, and future directions

BACKGROUND

There are many benefits of data sharing, including the promotion of new research from effective use of existing data, replication of findings through re-analysis of pooled data files, meta-analysis using individual patient data, and reinforcement of open scientific inquiry. A randomized controlled trial is considered as the 'gold standard' for establishing treatment effectiveness, but clinical trial research is very costly, and sharing data is an opportunity to expand the investment of the clinical trial beyond its original goals at minimal costs.

PURPOSE

We describe the goals, developments, and usage of the Data Share website (http://www.ctndatashare.org) for the National Drug Abuse Treatment Clinical Trials Network (CTN) in the United States, including lessons learned, limitations, and major revisions, and considerations for future directions to improve data sharing.

METHODS

Data management and programming procedures were conducted to produce uniform and Health Insurance Portability and Accountability Act (HIPAA)-compliant de-identified research data files from the completed trials of the CTN for archiving, managing, and sharing on the Data Share website.

RESULTS

Since its inception in 2006 and through October 2012, nearly 1700 downloads from 27 clinical trials have been accessed from the Data Share website, with the use increasing over the years. Individuals from 31 countries have downloaded data from the website, and there have been at least 13 publications derived from analyzing data through the public Data Share website.

LIMITATIONS

Minimal control over data requests and usage has resulted in little information and lack of control regarding how the data from the website are used. Lack of uniformity in data elements collected across CTN trials has limited cross-study analyses.

CONCLUSIONS

The Data Share website offers researchers easy access to de-identified data files with the goal to promote additional research and identify new findings from completed CTN studies. To maximize the utility of the website, ongoing collaborative efforts are needed to standardize the core measures used for data collection in the CTN studies with the goal to increase their comparability and to facilitate the ability to pool data files for cross-study analyses.

Transitions in illicit drug use status over 3 years: a prospective analysis of a general population sample

OBJECTIVE

The authors examined 3-year transitions among nonuse, asymptomatic use, and problem use of illicit drugs for U.S. adults in the general household population.

METHOD

Data were from the nationally representative National Epidemiologic Survey on Alcohol and Related Conditions, a study of 34,653 adults interviewed twice, 3 years apart. Respondents were categorized on three mutually exclusive categories of baseline drug status: past-year nonusers (N=32,675), past-year asymptomatic drug users (N=861), and past-year symptomatic drug users (N=1,117). Symptomatic drug use, or problem use, was defined as presence of one or more symptoms that operationalize DSM-IV drug abuse and dependence criteria. The authors assessed sociodemographic, health, substance use, and psychiatric covariates for association with 3-year transitions to different status categories.

RESULTS

Among baseline nonusers, 95.4% continued to be nonusers at follow-up, 2.1% became asymptomatic users, and 2.5% developed problem use. Among baseline asymptomatic users, 66.6% had stopped using drugs at follow-up, 14.3% continued to be asymptomatic users, and 19.1% had developed problem use. Nearly half (49.0%) of those with problem use at baseline had stopped using drugs at follow-up, 10.9% had transitioned to asymptomatic use, and 40.1% continued to have problem use. Younger age, male sex, white race, and not being married were associated with progression from nonuse to use or problem use, as were alcohol and tobacco use and disorders, major depression, and schizotypal, borderline, and narcissistic personality disorders. Panic disorder and avoidant personality disorder were associated with less progression.

CONCLUSIONS

Transitions in drug use status are common. The finding that alcohol and tobacco variables and co-occurring psychopathology are important correlates of transitions suggests the value of addressing all co-occurring disorders and substance use in patient assessments and treatment planning, both to prevent adverse transitions and to promote positive transitions.

Using electronic health records data to assess comorbidities of substance use and psychiatric diagnoses and treatment settings among adults

OBJECTIVE

To examine prevalences of substance use disorders (SUD) and comprehensive patterns of comorbidities among psychiatric patients ages 18-64 years (N = 40,099) in an electronic health records (EHR) database.

METHOD

DSM-IV diagnoses among psychiatric patients in a large university system were systematically captured: SUD, anxiety (AD), mood (MD), personality (PD), adjustment, childhood-onset, cognitive/dementia, dissociative, eating, factitious, impulse-control, psychotic (schizophrenic), sexual/gender identity, sleep, and somatoform diagnoses. Comorbidities and treatment types among patients with a SUD were examined.

RESULTS

Among all patients, 24.9% (n = 9984) had a SUD, with blacks (35.2%) and Hispanics (32.9%) showing the highest prevalence. Among patients with a SUD, MD was prevalent across all age groups (50.2-56.6%). Patients aged 18-24 years had elevated odds of comorbid PD, adjustment, childhood-onset, impulse-control, psychotic, and eating diagnoses. Females had more PD, AD, MD, eating, and somatoform diagnoses, while males had more childhood-onset, impulse-control, and psychotic diagnoses. Blacks had greater odds than whites of psychotic and cognitive/dementia diagnoses, while whites exhibited elevated odds of PA, AD, MD, childhood-onset, eating, somatoform, and sleep diagnoses. Women, blacks, and Native American/multiple-race adults had elevated odds of using inpatient treatment; men, blacks, and Hispanics had increased odds of using psychiatric emergency care. Comorbid MD, PD, adjustment, somatoform, psychotic, or cognitive/dementia diagnoses increased inpatient treatment.

CONCLUSION

Patients with a SUD, especially minority members, use more inpatient or psychiatric emergency care than those without. Findings provide evidence for research on understudied diagnoses and underserved populations in the real-world clinical settings.

Evaluating brief screeners to discriminate between drug use disorders in a sample of treatment-seeking adults

OBJECTIVE

The objective was to identify a potential core set of brief screeners for the detection of individuals with a substance use disorder (SUD) in medical settings.

METHOD

Data were from two multisite studies that evaluated stimulant use outcomes of an abstinence-based contingency management intervention as an addition to usual care (National Drug Abuse Treatment Clinical Trials Network trials 006-007). The sample comprised 847 substance-using adults who were recruited from 12 outpatient substance abuse treatment settings across the United States. Alcohol and drug use disorders were assessed by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Checklist. Data were analyzed by factor analysis, item response theory (IRT), sensitivity and specificity procedures.

RESULTS

Comparatively prevalent symptoms of dependence, especially inability to cut down for all substances, showed high sensitivity for detecting an SUD (low rate of false negative). IRT-defined severe (infrequent) and low discriminative items, especially withdrawal for alcohol, cannabis and cocaine, had low sensitivity in identifying cases of an SUD. IRT-defined less severe (frequent) and high discriminative items, including inability to cut down or taking larger amounts than intended for all substances and withdrawal for amphetamines and opioids, showed good-to-high values of area under the receiver operating characteristic curve in classifying cases and noncases of an SUD.

CONCLUSION

Findings suggest the feasibility of identifying psychometrically reliable substance dependence symptoms to develop a two-item screen for alcohol and drug disorders.