Opioid dependence latent structure: two classes with differing severity?

Early Childhood Behavioral and Academic Antecedents of Lifetime Opioid Misuse among Urban Youth

OBJECTIVE

Opioid misuse has become an epidemic in the United States. In the present study, we examine potential malleable early childhood predictors of opioid misuse including whether childhood achievement, aggressive behavior, attention problems, and peer social preference/likability in first grade predicted opioid misuse and whether these relationships differed depending on participant sex.

METHOD

Data are drawn from three cohorts of participants (N = 1,585; 46.7% male) recruited in first grade as part of a series of elementary school-based, universal preventive interventions conducted in a Mid-Atlantic region of the US. In first grade, participants completed standardized achievement tests, teachers reported on attention problems, and peers nominated their classmates with respect to their aggressive behavior and social preference/likability. At approximately age 20, participants reported on their misuse of opioids defined as lifetime use of heroin or misuse of prescription opioids.

RESULTS

Higher levels of peer nominations for aggressive behavior in first grade predicted a greater likelihood of opioid misuse. An interaction between participant sex and attention problems was observed such that females higher in attention problems were more likely to misuse opioids, particularly prescription opioids, than females lower in attention problems. An interaction was also found between participant sex and peer likability such that males lower in peer-nominated likability were more likely to misuse opioids relative to males higher in likability.

CONCLUSION

Given the malleable nature of attention problems, aggression, and social skills in early childhood, prevention programs that target these behaviors during this developmental period may attenuate risk for opioid misuse.

Problematic Opioid Use: A Scoping Literature Review of Profiles

Background and Objectives:

Problematic opioid use can be defined as opioid use behaviors leading to social, medical, or psychological consequences. In some instances, people presenting problematic opioid use can also meet criteria for an opioid use disorder. A growing body of literature highlights different types of people who use opioids, with contrasting characteristics and initiation patterns. In recent years, dynamic trends in opioid use have been documented and studies have demonstrated a shift in profiles.

Methods:

A scoping literature review was conducted to identify profiles of people presenting problematic opioid use, in order to support the development of tailored interventions and services.

Results:

Nine articles met the inclusion criteria. Five classifications emerge from the literature reviewed to distinguish types of people presenting problematic opioid use, according to: (1) the type of opioids used, (2) the route of opioid administration, (3) the level of quality of life, (4) patterns of other drugs used, and (5) dependence severity. While samples, concepts, and measurement tools vary between studies, the most salient finding might be the distinct profile of people presenting problematic use of pharmaceutical-type opioids.

Discussion and Conclusions:

This scoping review highlights that few studies address distinctive profiles of people presenting problematic opioid use. Geographical and chronological differences suggest that local timely assessments may be needed to tailor the service offer to specific needs.

Scientific Significance:

Future studies should focus on providing a deep understanding of distinct experiential perspectives and service needs, through exploratory quantitative and qualitative designs.

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.

The global burden of disease attributable to alcohol and drug use in 195 countries and territories, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

Alcohol and drug use can have negative consequences on the health, economy, productivity, and social aspects of communities. We aimed to use data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 to calculate global and regional estimates of the prevalence of alcohol, amphetamine, cannabis, cocaine, and opioid dependence, and to estimate global disease burden attributable to alcohol and drug use between 1990 and 2016, and for 195 countries and territories within 21 regions, and within seven super-regions. We also aimed to examine the association between disease burden and Socio-demographic Index (SDI) quintiles.

METHODS

We searched PubMed, EMBASE, and PsycINFO databases for original epidemiological studies on alcohol and drug use published between Jan 1, 1980, and Sept 7, 2016, with out language restrictions, and used DisMod-MR 2.1, a Bayesian meta-regression tool, to estimate population-level prevalence of substance use disorders. We combined these estimates with disability weights to calculate years of life lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs) for 1990-2016. We also used a comparative assessment approach to estimate burden attributable to alcohol and drug use as risk factors for other health outcomes.

FINDINGS

Globally, alcohol use disorders were the most prevalent of all substance use disorders, with 100·4 million estimated cases in 2016 (age-standardised prevalence 1320·8 cases per 100 000 people, 95% uncertainty interval [95% UI] 1181·2-1468·0). The most common drug use disorders were cannabis dependence (22·1 million cases; age-standardised prevalence 289·7 cases per 100 000 people, 95% UI 248·9-339·1) and opioid dependence (26·8 million cases; age-standardised prevalence 353·0 cases per 100 000 people, 309·9-405·9). Globally, in 2016, 99·2 million DALYs (95% UI 88·3-111·2) and 4·2% of all DALYs (3·7-4·6) were attributable to alcohol use, and 31·8 million DALYs (27·4-36·6) and 1·3% of all DALYs (1·2-1·5) were attributable to drug use as a risk factor. The burden of disease attributable to alcohol and drug use varied substantially across geographical locations, and much of this burden was due to the effect of substance use on other health outcomes. Contrasting patterns were observed for the association between total alcohol and drug-attributable burden and SDI: alcohol-attributable burden was highest in countries with a low SDI and middle-high middle SDI, whereas the burden due to drugs increased with higher S DI level.

INTERPRETATION

Alcohol and drug use are important contributors to global disease burden. Effective interventions should be scaled up to prevent and reduce substance use disease burden.

FUNDING

Bill & Melinda Gates Foundation and Australian National Health and Medical Research Council.

The latent trait of ICD-11 nicotine dependence criteria: Dimensional and categorical phenotypes

We aimed to identify phenotypes of DSM-ICD nicotine dependence among a representative sample of lifetime weekly smokers in the largest metropolitan area in South America. Data came from 1,387 lifetime weekly smokers in the São Paulo Megacity Mental Health Survey. We used exploratory factor analysis (EFA) and latent class analysis (LCA) on ICD-11 nicotine dependence proposed criteria to explore dimensionality and phenotypes profiles, followed by logistic regression models to examine the association between latent classes and socio-demographic, psychiatric and chronic medical conditions. Analyses were performed using Mplus taking into account the complex survey design features. An unidimensional model had the best EFA fit with high loadings on all criteria. Response patterns detected by LCA indicated class differences based on severity continuum: a "non-symptomatic class" (32.0%), a "low-moderate symptomatic class" (34.9%)-with high probability of the criterion "use in larger amounts", and a "high-moderate symptomatic class" (33.1%). We found an association between high-income and the intermediate class that differs from findings in high-income countries, and high likelihood of psychiatric comorbidity among the most symptomatic smokers. The best dimensional model that pulled together nicotine dependence criteria supported a single factor, in concordance with the changes proposed for ICD-11.

Effectiveness of treatment for opioid use disorder: A national, five-year, prospective, observational study in England

BACKGROUND

This the first 5-year effectiveness study of publicly funded treatment for opioid use disorder (OUD) in England.

METHODS

All adults initiating treatment in 2008/09 in all 149 local treatment systems reporting to the National Drug Treatment Monitoring System (n=54,347). Admission polydrug use sub-populations were identified by Latent Class Analysis. The treatment outcome measure was 'successful completion and no re-presentation within six months' (SCNR) analysed by multilevel, multivariable logistic regression and funnel plots to contrast outcome by treatment system.

RESULTS

SCNR was achieved by 21.9%. Heroin and crack cocaine users were significantly less likely to achieve this outcome than patients who used heroin only (adjusted odds ratio [AOR] 0.90; 95% confidence interval [CI] 0.85-0.95). Older patients (AOR 1.09; CI 1.07-1.11), those employed (AOR 1.27; CI 1.18-1.37) and those enrolled for longer treatment were more likely to achieve the outcome measure. After risk adjustment, the local treatment systems that achieved substantially better outcome performance (14/149) had a lower rate of opiate prevalence in the local population at time of study initiation (incidence rate difference [IRD] 4.1; CI 4.0-4.2), fewer criminal offences per thousand (IRD 28.5; CI 28.1-28.8) and lower drug-related deaths per million (IRD 5.9; CI 5.9-5.9).

CONCLUSIONS

In an English national study, one fifth of patients successful completed treatment for OUD and did not present for further treatment within six months. Longer time in treatment increases the probability of achieving and maintaining clinical benefit from treatment. After risk-adjustment, an important minority of treatment systems achieve substantially better outcome performance.

Trajectories of heroin use: 10-11-year findings from the Australian Treatment Outcome Study

AIMS

To identify trajectories of heroin use in Australia, predictors of trajectory group membership and subsequent outcomes among people with heroin dependence over 10-11 years.

DESIGN

Longitudinal cohort study.

SETTING

Sydney, Australia.

PARTICIPANTS

A total of 615 participants were recruited between 2001 and 2002 as part of the Australian Treatment Outcome Study (66.2% male; mean age 29 years). The predominance of the cohort (87.0%) was recruited upon entry to treatment (maintenance therapies, detoxification and residential rehabilitation), and the remainder from non-treatment settings (e.g. needle and syringe programmes). This analysis focused upon 428 participants for whom data on heroin use were available over 10-11 years following study entry.

MEASUREMENTS

Structured interviews assessed demographics, treatment history, heroin and other drug use, overdose, criminal involvement, physical health and psychopathology. Group-based trajectory modelling was used to: (i) identify trajectory groups based on use of heroin in each year, (ii) examine predictors of group membership and (iii) examine associations between trajectory group membership and 10-11-year outcomes.

FINDINGS

Six trajectory groups were identified [Bayesian Information Criterion (BIC) = -1927.44 (n = 4708); -1901.07 (n = 428)]. One in five (22.1%) were classified as having 'no decrease' in heroin use, with the probability of using remaining high during the 10-11 years (> 0.98 probability of use in each year). One in six (16.1%) were classified as demonstrating a 'rapid decrease to maintained abstinence'. The probability of heroin use among this group declined steeply in the first 2-3 years and continued to be low (< 0.01). The remaining trajectories represented other fluctuating patterns of use. Few baseline variables were found to predict trajectory group membership, but group membership was predictive of demographic, substance use and physical and mental health outcomes at 10-11 years.

CONCLUSIONS

Long-term trajectories of heroin use in Australia appear to show considerable heterogeneity during a decade of follow-up, with few risk factors predicting group membership. Just more than a fifth continued to use at high levels, while fewer than a fifth become abstinent early on and remained abstinent. The remainder showed fluctuating patterns.

Pathways through opiate use and offending: A systematic review

BACKGROUND

Although evidence points to a strong link between illicit drug use and crime, robust evidence for temporal order in the relationship is scant. We carried out a systematic review to assess the evidence for pathways through opiate/crack cocaine use and offending to determine temporal order.

METHODS

A systematic review sourced five databases, three online sources, bibliographies and citation mapping. Inclusion criteria were: focus on opiate/crack use, and offending; pre-drug use information; longitudinal design; corroborative official crime records. Rate ratios (RR) of post-drug use initiation to pre-drug use initiation were pooled using random effects meta-analysis.

RESULTS

20 studies were included; UK (9) and US (11). All were of opiate use. Mean age at (recorded) offending onset (16.7yrs) preceded mean age at opiate-use onset (19.6yrs). Substantial heterogeneity (over 80%: unexplained by meta-regression) meant that RRs were not pooled. The RR for total (recorded) offending ranged from 0.71 to 25.7 (10 studies; 22 subsamples: positive association, 4: equivocal, 1: negative association). Positive associations were observed in 14/15 independent samples; unlikely to be a chance finding (sign test p=0.001). Individual offence types were examined: theft (RR 0.63-8.3, 13 subsamples: positive, 9: equivocal, 1 negative); burglary (RR 0.74-50.0, 9 subsamples: positive, 13: equivocal); violence (RR 0.39-16.0, 6 subsamples: positive, 15: equivocal); and robbery (RR 0.50-5.0, 5 subsamples: positive, 15: equivocal).

CONCLUSIONS

Available evidence suggests that onset-opiate use accelerates already-existing offending, particularly for theft. However, evidence is out of date, with studies characterised by heterogeneity and failure to use a matched non-opiate-user comparison group to better-establish whether onset-opiate use is associated with additional crime.

Opioid withdrawal, craving, and use during and after outpatient buprenorphine stabilization and taper: a discrete survival and growth mixture model

INTRODUCTION

Most patients relapse to opioids within one month of opioid agonist detoxification, making the antecedents and parallel processes of first use critical for investigation. Craving and withdrawal are often studied in relationship to opioid outcomes, and a novel analytic strategy applied to these two phenomena may indicate targeted intervention strategies.

METHODS

Specifically, this secondary data analysis of the Prescription Opioid Addiction Treatment Study used a discrete-time mixture analysis with time-to-first opioid use (survival) simultaneously predicted by craving and withdrawal growth trajectories. This analysis characterized heterogeneity among prescription opioid-dependent individuals (N=653) into latent classes (i.e., latent class analysis [LCA]) during and after buprenorphine/naloxone stabilization and taper.

RESULTS

A 4-latent class solution was selected for overall model fit and clinical parsimony. In order of shortest to longest time-to-first use, the 4 classes were characterized as 1) high craving and withdrawal, 2) intermediate craving and withdrawal, 3) high initial craving with low craving and withdrawal trajectories and 4) a low initial craving with low craving and withdrawal trajectories. Odds ratio calculations showed statistically significant differences in time-to-first use across classes.

CONCLUSIONS

Generally, participants with lower baseline levels and greater decreases in craving and withdrawal during stabilization combined with slower craving and withdrawal rebound during buprenorphine taper remained opioid-free longer. This exploratory work expanded on the importance of monitoring craving and withdrawal during buprenorphine induction, stabilization, and taper. Future research may allow individually tailored and timely interventions to be developed to extend time-to-first opioid use.

Latent class analysis of DSM-5 criteria for opioid use disorders: results from the Iranian National Survey on Mental Health

BACKGROUND

Assessments of DSM-IV and DSM-5 criteria with sample populations of opioid users are limited. This study aimed to determine the number of latent classes in opioid users and assessment of the proposed revisions to the DSM-5 opioid use disorder (OUD) criteria.

METHODS

Data came from the 2011 Iranian National Mental Health Survey (IranMHS) on 7,886 participants aged 15-64 years living in Iran. We used the Composite International Diagnostic Interview (CIDI) version 2.1 in all respondents who indicated using opioids at least 5 times in the previous 12 months (n = 236).

RESULTS

A three-class model provided the best fit of all the models tested. Classes showed a spectrum of severity that was compatible with the DSM-5 classification. 'Legal problems' and 'desire to cut down' showed poor discrimination between classes. The weighted prevalence of OUD using DSM-5 was 20.7% higher than with DSM-IV.

CONCLUSIONS

RESULTS support the grouping based on severity of symptoms, combining abuse and dependence into a single diagnosis, omitting legal problems, and addition of craving as a new criterion.

Family-based association analysis of alcohol dependence criteria and severity

BACKGROUND

Despite the high heritability of alcohol dependence (AD), the genes found to be associated with it account for only a small proportion of its total variability. The goal of this study was to identify and analyze phenotypes based on homogeneous classes of individuals to increase the power to detect genetic risk factors contributing to the risk of AD.

METHODS

The 7 individual DSM-IV criteria for AD were analyzed using latent class analysis (LCA) to identify classes defined by the pattern of endorsement of the criteria. A genome-wide association study was performed in 118 extended European American families (n = 2,322 individuals) densely affected with AD to identify genes associated with AD, with each of the 7 DSM-IV criteria, and with the probability of belonging to 2 of 3 latent classes.

RESULTS

Heritability for DSM-IV AD was 61% and ranged from 17 to 60% for the other phenotypes. A single nucleotide polymorphism (SNP) in the olfactory receptor OR51L1 was significantly associated (7.3 × 10(-8) ) with the DSM-IV criterion of persistent desire to, or inability to, cut down on drinking. LCA revealed a 3-class model: the "low-risk" class (50%) rarely endorsed any criteria and none met criteria for AD; the "moderate-risk" class (33%) endorsed primarily 4 DSM-IV criteria and 48% met criteria for AD; and the "high-risk" class (17%) manifested high endorsement probabilities for most criteria and nearly all (99%) met criteria for AD. One SNP in a sodium leak channel NALCN demonstrated genome-wide significance with the high-risk class (p = 4.1 × 10(-8) ). Analyses in an independent sample did not replicate these associations.

CONCLUSIONS

We explored the genetic contribution to several phenotypes derived from the DSM-IV AD criteria. The strongest evidence of association was with SNPs in NALCN and OR51L1.

ANKK1, TTC12, and NCAM1 polymorphisms and heroin dependence: importance of considering drug exposure

CONTEXT

The genetic contribution to liability for opioid dependence is well established; identification of the responsible genes has proved challenging.

OBJECTIVE

To examine association of 1430 candidate gene single-nucleotide polymorphisms (SNPs) with heroin dependence, reporting here only the 71 SNPs in the chromosome 11 gene cluster (NCAM1, TTC12, ANKK1, DRD2) that include the strongest observed associations.

DESIGN

Case-control genetic association study that included 2 control groups (lacking an established optimal control group).

SETTING

Semistructured psychiatric interviews.

PARTICIPANTS

A total of 1459 Australian cases ascertained from opioid replacement therapy clinics, 531 neighborhood controls ascertained from economically disadvantaged areas near opioid replacement therapy clinics, and 1495 unrelated Australian Twin Registry controls not dependent on alcohol or illicit drugs selected from a twin and family sample.

MAIN OUTCOME MEASURE

Lifetime heroin dependence.

RESULTS

Comparison of cases with Australian Twin Registry controls found minimal evidence of association for all chromosome 11 cluster SNPs (P ≥ .01); a similar comparison with neighborhood controls revealed greater differences (P ≥ 1.8 × 10(-4)). Comparing cases (n = 1459) with the subgroup of neighborhood controls not dependent on illicit drugs (n = 340), 3 SNPs were significantly associated (correcting for multiple testing): ANKK1 SNP rs877138 (most strongly associated; odds ratio = 1.59; 95% CI, 1.32-1.92; P = 9.7 × 10(-7)), ANKK1 SNP rs4938013, and TTC12 SNP rs7130431. A similar pattern of association was observed when comparing illicit drug-dependent (n = 191) and nondependent (n = 340) neighborhood controls, suggesting that liability likely extends to nonopioid illicit drug dependence. Aggregate heroin dependence risk associated with 2 SNPs, rs877138 and rs4492854 (located in NCAM1), varied more than 4-fold (P = 2.7 × 10(-9) for the risk-associated linear trend).

CONCLUSIONS

Our results provide further evidence of association for chromosome 11 gene cluster SNPs with substance dependence, including extension of liability to illicit drug dependence. Our findings highlight the necessity of considering drug exposure history when selecting control groups for genetic investigations of illicit drug dependence.

Profiles of quality of life in opiate-dependent individuals after starting methadone treatment: a latent class analysis

BACKGROUND

This study aimed to identify classes of quality of life (QoL) among opiate-dependent individuals five to ten years after starting methadone treatment in order to tailor services to the needs of this population.

METHODS

A cross-sectional study of 159 opiate-dependent individuals who started outpatient methadone treatment in the region of Ghent, Belgium, between 1997 and 2002. A face-to-face structured interview was administered based on the Lancashire Quality of Life Profile, the EuropASI, Brief Symptom Inventory and the Verona Service Satisfaction Scale for Methadone Treatment. Latent class analysis was used to determine patterns of QoL. Analyses of variance and chi-square tests were used to test whether class membership was related to socio-demographic, health- and drug-related variables.

RESULTS

Based on fit criteria, a three-class model was selected. Class Low (14.5%), 'opiate-dependent individuals living in marginal conditions', is characterised by low QoL scores on all domains. Class Intermediate (25.8%), 'stabilized, but socially excluded opiate-dependent individuals' shows high scores on the domains 'safety' and 'living situation', but low scores on all other QoL domains. Class High (59.7%), 'socially included opiate-dependent individuals', is characterised by high QoL scores on all domains, except 'finances'.

CONCLUSION

The findings of this study illustrate the existence of different profiles of QoL among opiate-dependent individuals after starting methadone maintenance treatment and demonstrate the need for a continuing care approach. Insight into distinct classes of QoL can be used to design person-centred support, relevant to an individual's personal life.

Analyses related to the development of DSM-5 criteria for substance use related disorders: 2. Proposed DSM-5 criteria for alcohol, cannabis, cocaine and heroin disorders in 663 substance abuse patients

BACKGROUND

A number of changes have been proposed and investigated in the criteria for substance use disorders in DSM-5. However, although clinical utility of DSM-5 is a high priority, relatively little of the empirical evidence supporting the changes was obtained from samples of substance abuse patients.

METHODS

Proposed changes were examined in 663 patients in treatment for substance use disorders, evaluated by experienced clinicians using the Psychiatric Research Interview for Substance and Mental Disorders (PRISM). Factor and item response theory analysis was used to investigate the dimensionality and psychometric properties of alcohol, cannabis, cocaine and heroin abuse and dependence criteria, and craving.

RESULTS

The seven dependence criteria, three of the abuse criteria (hazardous use; social/interpersonal problems related to use; neglect of roles to use), and craving form a unidimensional latent trait for alcohol, cannabis, cocaine and heroin. Craving did not add significantly to the total information offered by the dependence criteria, but adding the three abuse criteria and craving together did significantly increase total information for the criteria sets associated with alcohol, cannabis and heroin.

CONCLUSION

Among adult patients in treatment for substance disorders, the alcohol, cannabis, cocaine and heroin criteria for dependence, abuse (with the exception of legal problems), and craving measure a single underlying dimension. Results support the proposal to combine abuse and dependence into a single diagnosis in the DSM-5, omitting legal problems. Mixed support was provided for the addition of craving as a new criterion, warranting future studies of this important construct in substance use disorders.

30-year trajectories of heroin and other drug use among men and women sampled from methadone treatment in California

BACKGROUND

This study examines 30-year trajectories of heroin and other drug use among men and women who were in methadone maintenance treatment in California in the late 1970s and interviewed in 1978-1981.

METHODS

Nearly half (N=428; 46.8%) of the original study sample (N=914) was deceased. Of the remaining 486 subjects, 343 (44.3% female) completed a follow-up interview in 2005-2009 (70.6% of those not deceased). Average age at follow-up was 58.3 (SD=4.9) years for males and 55.0 (SD=4.1) years for females. Longitudinal data was obtained on their drug use, treatment participation, and criminal justice status over the follow-up period. Trajectory group modeling was used to identify distinctive trajectory groups based on monthly averages of heroin and other drug use per year; group differences were examined.

RESULTS

Four heroin and five alcohol and other drug (AOD) trajectory groups were identified. A greater proportion of women (60%) were in the "rapid decrease" heroin group (odds of use less than 10% by 10 years following initiation of use) as compared with the other groups. More rapid decrease of heroin use was associated with increases in AOD use, whereas a gradual decrease in heroin use was associated with a gradual decrease in AOD use. More school problems and earlier age at onset of heroin use and first arrest were associated with more persistent heroin use.

CONCLUSION

Heroin-use trajectories were linked with changes in AOD use. Childhood antecedents of heroin-use trajectories were identified as well as gender differences.