Patterns of substance use and mortality risk in a cohort of 'hard-to-reach' polysubstance users

The recovery experiences of homeless service users with substance use disorder: A systematic review and qualitative meta-synthesis

BACKGROUND

The relationship between homelessness and substance use disorder (SUD) is layered and complex. Adults pursuing recovery while dealing with homelessness and SUD face many challenges. Little research has inspected qualitative first-person accounts of recovery in the context of homelessness and SUD, and few studies have employed conceptualisations of recovery beyond abstinence. In this systematic review study, we examine the qualitative literature on the recovery experiences of adult homeless service users with SUD.

METHODS

2,042 records were identified via database and secondary searching strategy. After title and abstract and full text screening, 15 eligible studies remained. Critical Appraisal Skills Programme quality appraisal criteria was used to assess potential bias in the studies. Meta-ethnography was employed to synthesise extracted data.

RESULTS

Four themes were generated from the extracted data: Two sides of the Service Coin; Navigating Relationships; Recovery Practices and Personal Attributes; and Housing as Foundational for Recovery.

CONCLUSION

Unconditional housing, a broad array of supports, opportunities to contribute to society, and family reunification supports all facilitate the development of recovery for adults with SUD experiencing homelessness. Implications for policy are discussed.

Prevalence of comorbid substance use disorders among people with opioid use disorder: A systematic review & meta-analysis

BACKGROUND

Comorbid substance use disorders (SUDs) among people with opioid use disorder (OUD) contribute to poor clinical outcomes, including overdose and mortality. We present the first systematic review and meta-analysis to estimate the prevalence of specific non-opioid SUDs among people with OUD.

METHODS

We searched Embase, PsycINFO, and MEDLINE from 1990 to 2022 for studies that used Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) criteria to assess the prevalence of non-opioid SUDs among individuals with OUD. We used random-effects meta-analyses with 95% Confidence Intervals (CIs) to pool current and lifetime prevalence estimates separately. Meta-regressions and stratified meta-analyses were used to examine differences in prevalence estimates by sample characteristics and methodological factors.

RESULTS

Of the 36,971 publications identified, we included data from 194 studies and 77,212 participants with OUD. The prevalence of any comorbid SUD among people with OUD was 59.5% (95%CI 49.1-69.5%) for current non-opioid SUDs, with 72.0% (95%CI 52.5-87.9%) experiencing a comorbid SUD in their lifetime. Of the studies that examined current comorbid SUDs, cocaine use disorder (30.5%, 95%CI 23.0-38.7%) was most common, followed by alcohol (27.1%, 95%CI 24.4- 30.0%), cannabis (22.7%, 95%CI 19.0-26.6%), sedative (16.1%, 95%CI 13.1-19.3%), and methamphetamine (11.4%, 95%CI 6.8-17.1%) use disorders. Substantial heterogeneity (I2>90%) across estimates was observed. Substantial heterogeneity (I2>90%) was observed across estimates, with significant variations in prevalence identified across geographic locations, recruitment settings, and other study-level factors.

CONCLUSION

Findings from this study emphasize the importance of comorbid SUD treatment access for people with OUD. Our estimates can inform the provision of treatment and harm reduction strategies for people with OUD and specific subpopulations.

Mortality among people who inject drugs - the interwoven roles of fentanyl and HIV: a community-based cohort study

BACKGROUND

Excess all-cause mortality is a key indicator for assessing direct and indirect consequences of injection drug use and data are warranted to delineate sub-populations within people who inject drugs at higher risk of death. Our aim was to examine mortality and factors associated with mortality among people who inject drugs in Estonia.

METHODS

Retrospective cohort study using data from people who inject drugs recruited in the community with linkage to death records. Standardized mortality ratios were used to compare the cohort mortality to the general population and potential predictors of death were examined through survival analysis (Cox regression). The cohort include a total of 1399 people who inject drugs recruited for cross-sectional surveys using respondent driven sampling between 2013 and 2018 in Estonia. A cohort with follow-up through 2019 was formed with linkage to national causes of death registry.

RESULTS

Among 1399 participants with 4684 person-years of follow-up, 10% were deceased by 2019. The all-cause mortality rate in the cohort was 28.9 per 1000 person-years (95% confidence interval 25.3-35.3). Being HIV positive, injecting mainly opioids (fentanyl), living in the capital region and the main source of income other than work were associated with greater mortality risk.

CONCLUSIONS

While low-threshold services have been available for a long time for people who inject drugs, there is still a need to widen the availability and integration of services, particularly the integration of HIV and opioid treatment.

No decline in drug overdose deaths in Norway: An ecological approach to understanding at-risk groups and the impact of interventions

Aim: This Norwegian case study examines groups at risk of drug overdose deaths, evidence-based harm reduction interventions, low-threshold services and treatment implemented, as well as trends in drug overdose deaths between 2010 and 2021. We aimed to explore the relevance of interventions for at-risk groups and discuss their potential impact on drug overdose trends. Method/data: Using an ecological approach, we analysed the following: (1) groups identified through latent profile analysis (LPA) among a sample of 413 high-risk drug users collected in 2010-2012, supplemented with other relevant studies up to 2021; (2) published information on harm-reduction interventions, low-threshold services and treatment in Norway; and (3) nationwide drug overdose mortality figures supplemented with published articles on the topic. Results: High-risk drug users in 2010-2012 commonly engaged in frequent illegal drug use, injecting and poly-drug use (including pharmaceutical opioids), which continued into following decade. The interventions implemented between 2010 and 2021 were relevant for at-risk groups identified in the surveys. However, there was no decrease in the trend of drug overdose deaths up to 2021. While relevant interventions may have mitigated a theoretical increase in mortality, new at-risk groups may have contributed to fatal outcomes associated with pharmaceutical opioids. Conclusion: The interventions were relevant to the risk groups identified among high-risk drug users and potentially effective in preventing an increase in drug overdose trends. However, tailored interventions are needed for individuals at risk of death from prescribed opioids. Comprehensive studies encompassing all at-risk populations, including both legal and non-medical users of prescription opioids, are needed.

Mortality risk and causes of death among people who use opioids in a take-home naloxone cohort

BACKGROUND

People who use opioids (PWUO) have an excess mortality from a range of causes. The cumulative effect of behavioral, social, and health risk factors complicates the interpretation of the effects of suitable interventions. This study explores mortality causes among a cohort of PWUO in the take-home naloxone (THN) program.

METHODS

This was a prospective cohort study of PWUO who received THN between 2015 and 2023. Participant data was linked with death registry data. Crude mortality rates and standardized mortality ratios (SMRs) were calculated for all causes, internal causes, and accidental opioid overdoses (AOOs). In addition to age and gender, risk factors like main route of administration, polydrug use, self-experienced overdoses, and using while alone were fitted in a Cox Regression model to explore factors associated with mortality.

RESULTS

The 2194 participants had a considerably higher mortality ratio for all causes investigated when compared to the general population (SMR=10.9, 95 % CI = 9.3,12.6). AOOs were the most prevalent cause of death (49 %). Those who reported frequent opioid use while alone had an elevated risk of dying of 2.6 (95 % CI = 1.1,6.4) compared to those who never used while alone.

CONCLUSIONS

Frequent opioid use while alone was associated with elevated mortality risk, supporting the importance of overdose prevention education with naloxone distribution, and additional efforts to improve environmental and social areas for safer drug-use practices among PWUO. The variety of mortality causes found in this study illustrates the need for multifaceted and targeted interventions for people at risk of overdosing.

Longitudinal polysubstance use patterns and non-fatal overdose: A repeated measures latent class analysis

BACKGROUND

Polysubstance use (PSU) is common among people who use opioids (PWUO) and has been associated with drug-related harms. We aimed to identify latent longitudinal PSU classes among a cohort of PWUO and characterize non-fatal overdose risks among different sub-classes over time.

METHODS

We used longitudinal data (2005-2018) from three ongoing prospective cohorts of people who use drugs in Vancouver, Canada. The primary outcome of interest was self-reported non-fatal overdose during the past six months. The primary exposure of interest was longitudinal PSU patterns among PWUO, obtained from repeated measures latent class analysis (RMLCA) of weekly substance use-related outcome indicators. Multivariable generalized estimating equations models were built to assess the association between latent PSU class membership and non-fatal overdose, adjusting for potential sociodemographic, behavioural, and structural confounders.

RESULTS

2627 PWUO were included in the analysis, and 1094 (41.6 %) had experienced at least one non-fatal overdose during the study period. RMLCA revealed five distinct latent longitudinal PSU classes, including low/infrequent use (Class 1; 30 %), primarily opioid and methamphetamine use (Class 2; 22 %), primarily cannabis use (Class 3; 15 %), primarily opioid and crack use (Class 4; 29 %), and frequent PSU (Class 5; 4 %). In comparison with Class 1 (low), membership in all latent PSU classes except Class 3 (cannabis) was associated with increased odds of non-fatal overdose: Class 2 (opioids + meth) vs. Class 1 (Adjusted odds ratios [aOR] = 2.20, 95 % confidence intervals [CI]: 1.51-3.22), Class 4 (opioids + crack) vs. Class 1 (aOR = 1.06, 95 % CI: 0.85-1.33), and Class 5 (frequent) vs. Class 1 (aOR = 2.39, 95 % CI: 1.92-2.97).

CONCLUSION

Our findings highlighted the heterogeneous characteristics of PWUO in terms of patterns of PSU and non-fatal overdose risk. The diverse nature of PWUO and the potential additive or multiplicative impact of using several substances on overdoses should be reflected across the substance use treatment continuum and care provision.

Assessing the relationship between drug use initiation age and racial characteristics

Initiating drug use in adolescence is associated with greater risk of drug misuse and dependence in adulthood and co-occurring mental health disorders. Initiating drug use in adulthood has been linked to higher-risk drug use networks and primary use of "harder drugs". The aim of our research is to examine racial/ethnic differences in age at drug use initiation and its relationship with adult outcomes. Based on data from the 2019 National Survey on Drug Use and Health (NSDUH), we used survey-weighted Poisson regression models with robust variance to identify associations between racial characteristics, age at drug use initiation, and three adult outcomes - past year polydrug use, substance use, and mental illness - adjusting for individual-level characteristics. Among 25,986 respondents who ever used drugs and reported their drug use initiation age, Asian-Americans reported the oldest drug use initiation age (19.5) on average, while Native Americans reported the youngest initiation age (16.6). While there were no significant differences in type of drug used during onset by race or ethnicity, generally, individuals start to use inhalants at the earliest age (17.4), while the misuse of sedatives is initiated at the oldest age (46.4). Initiation during late adolescence was associated with greater likelihood of a substance use disorder diagnosis, mental health diagnoses, and polydrug use in adulthood. Drug use prevention interventions should be tailored and accessible during adolescence to delay onset. Interventions that are culturally sensitive, screen for vulnerability to drug use, and offer age-appropriate services should be prioritized.

Polysubstance addiction patterns among 7,989 individuals with cocaine use disorder

To characterize polysubstance addiction (PSA) patterns of cocaine use disorder (CoUD), we performed a latent class analysis (LCA) in 7,989 participants with a lifetime DSM-5 diagnosis of CoUD. This analysis identified three PSA subgroups among CoUD participants (i.e., low, 17%; intermediate, 38%; high, 45%). While these subgroups varied by age, sex, and racial-ethnic distribution (p < 0.001), there was no difference with respect to education or income (p > 0.05). After accounting for sex, age, and race-ethnicity, the CoUD subgroup with high PSA had higher odds of antisocial personality disorder (OR = 21.96 vs. 6.39, difference-p = 8.08✕10-6), agoraphobia (OR = 4.58 vs. 2.05, difference-p = 7.04✕10-4), mixed bipolar episode (OR = 10.36 vs. 2.61, difference-p = 7.04✕10-4), posttraumatic stress disorder (OR = 11.54 vs. 5.86, difference-p = 2.67✕10-4), antidepressant medication use (OR = 13.49 vs. 8.02, difference-p = 1.42✕10-4), and sexually transmitted diseases (OR = 5.92 vs. 3.38, difference-p = 1.81✕10-5) than the low-PSA CoUD subgroup. These findings underscore the importance of modeling PSA severity and comorbidities when examining the clinical, molecular, and neuroimaging correlates of CoUD.

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.

Polysubstance addiction and psychiatric, somatic comorbidities among 7,989 individuals with cocaine use disorder: a latent class analysis

Aims

We performed a latent class analysis (LCA) in a sample ascertained for addiction phenotypes to investigate cocaine use disorder (CoUD) subgroups related to polysubstance addiction (PSA) patterns and characterized their differences with respect to psychiatric and somatic comorbidities.

Design

Cross-sectional study.

Setting

United States.

Participants

Adult participants aged 18-76, 39% female, 47% African American, 36% European American with a lifetime DSM-5 diagnosis of CoUD (N=7,989) enrolled in the Yale-Penn cohort. The control group included 2,952 Yale-Penn participants who did not meet for alcohol, cannabis, cocaine, opioid, or tobacco use disorders.

Measurements

Psychiatric disorders and related traits were assessed via the Semi-structured Assessment for Drug Dependence and Alcoholism. These features included substance use disorders (SUD), family history of substance use, sociodemographic information, traumatic events, suicidal behaviors, psychopathology, and medical history. LCA was conducted using diagnoses and diagnostic criteria of alcohol, cannabis, opioid, and tobacco use disorders.

Findings

Our LCA identified three subgroups of PSA (i.e., low, 17%; intermediate, 38%; high, 45%) among 7,989 CoUD participants. While these subgroups varied by age, sex, and racial-ethnic distribution (p<0.001), there was no difference on education or income (p>0.05). After accounting for sex, age, and race-ethnicity, the CoUD subgroup with high PSA had higher odds of antisocial personality disorder (OR=21.96 vs. 6.39, difference-p=8.08×10 -6 ), agoraphobia (OR=4.58 vs. 2.05, difference-p=7.04×10 -4 ), mixed bipolar episode (OR=10.36 vs. 2.61, difference-p=7.04×10 -4 ), posttraumatic stress disorder (OR=11.54 vs. 5.86, difference-p=2.67×10 -4 ), antidepressant medication use (OR=13.49 vs. 8.02, difference-p=1.42×10 -4 ), and sexually transmitted diseases (OR=5.92 vs. 3.38, difference-p=1.81×10 -5 ) than the low-PSA CoUD subgroup.

Conclusions

We found different patterns of PSA in association with psychiatric and somatic comorbidities among CoUD cases within the Yale-Penn cohort. These findings underscore the importance of modeling PSA severity and comorbidities when examining the clinical, molecular, and neuroimaging correlates of CoUD.

Traumatic experiences and PTSD symptoms in substance use disorder: A comparison of recovered versus current users

Introduction: The aim of this study was to investigate the prevalence of traumatic experiences and symptoms of posttraumatic stress disorder (PTSD) in treatment-seeking individuals with ongoing substance use disorder (SUD) compared to individuals who have recovered from SUD. Methods: Patients with SUD recruited from the STAYER study (N = 114) underwent an examination of alcohol and drug use, childhood trauma, negative life events and PTSD symptomatology. In this study, only participants with 12-month concurrent polysubstance use was included. Using historical data from the STAYER study, alcohol and drug trajectories were dichotomised as (1) current SUD (current SUD) or (2) recovered from substance use disorder (recovered SUD). Crosstabs and chi-tests were used to measure differences between groups. Results: Childhood maltreatment, traumatic experiences later in life and symptoms of concurrent PTSD were highly prevalent in the study population. We found no significant difference between the current and recovered SUD groups. Recovered women reported a lower prevalence of physical neglect (p = 0.031), but a higher prevalence of multiple lifetime traumas (p = 0.019) compared to women with current SUD. Both women with current SUD and recovered women reported a significantly higher prevalence of sexual aggression than men (p < 0.001 and p < 0.001, respectively). In addition, men who have recovered from SUD reported a lower prevalence of PTSD symptoms over cut-off 38 (p = 0.017), of re-experiencing (p = 0.036) and of avoidance (p = 0.015), compared to recovered women. Conclusion: Reported trauma did not differ between persons with current SUD and those who had recovered from SUD. Gender differences discovered in this study indicate the importance of developing individualised and gender-specific treatment models for comorbid PTSD/SUD.

Intimate partner violence, substance use, and health comorbidities among women: A narrative review

Exposure to intimate partner violence (IPV), including physical, sexual, and psychological violence, aggression, and/or stalking, impacts overall health and can have lasting mental and physical health consequences. Substance misuse is common among individuals exposed to IPV, and IPV-exposed women (IPV-EW) are at-risk for transitioning from substance misuse to substance use disorder (SUD) and demonstrate greater SUD symptom severity; this too can have lasting mental and physical health consequences. Moreover, brain injury is highly prevalent in IPV-EW and is also associated with risk of substance misuse and SUD. Substance misuse, mental health diagnoses, and brain injury, which are highly comorbid, can increase risk of revictimization. Determining the interaction between these factors on the health outcomes and quality of life of IPV-EW remains a critical need. This narrative review uses a multidisciplinary perspective to foster further discussion and research in this area by examining how substance use patterns can cloud identification of and treatment for brain injury and IPV. We draw on past research and the knowledge of our multidisciplinary team of researchers to provide recommendations to facilitate access to resources and treatment strategies and highlight intervention strategies capable of addressing the varied and complex needs of IPV-EW.

The Importance of Perceived Safety, Stigma and Pleasure for Solitary Injecting

Many people who inject drugs (PWID) inject when they are alone which increases the risk for drug-related mortality, and the majority of overdose-related deaths occur among solitary users in residential environments. Drawing on qualitative data from interviews with 80 PWID in Norway, this study explores the complex practices of solitary injecting. The analysis illustrates that the risk environments in which they participated involved high levels of distress, fear and stigma that made them prefer solitary injecting. This involved a perceived notion of safety from an unpredictable social environment. Stigma was described as causing additional harms and they therefore wanted to hide their drug-using practices. Finally, injecting drug use involved contextual pleasures that were maximised by injecting alone. The study illustrates how the risk environment the PWID inhabited caused additional harms, by which solitary injections was rationalized, despite its increased mortality risks. Future harm-reduction initiatives should reflect this important aspect.

Clustering patterns in polysubstance mortality in the United States in 2017: a multiple correspondence analysis of death certificate data

PURPOSE

The main goal of this analysis was to identify mortality patterns apparent when many drug classes are analyzed together.

METHODS

The Drug Involved Mortality database is a registry of drug terms mentioned on death certificates of all drug-related deaths in the United States. Means of total number of drugs involved and percentages of specific drug combinations were calculated. Dimensionality reduction using multiple correspondence analysis and hierarchical clustering identified clusters of drugs listed on death certificates.

RESULTS

An average of 2.4 specific drugs were listed on death certificates in 2017. For 9 of the top 10 drugs involved, over 80% of deaths involved at least one other drug. As expected, opioid drugs and psychostimulants clustered together, but other psychoactive substances (non-opioid analgesics, sedatives, antidepressants, antipsychotics) clustered together into multi-class groups. Other drugs (e.g., acetaminophen, oxymorphone) were frequently involved in polysubstance death, but did not cluster with any other specific drug. Deaths involving illicit drugs listed fewer drugs than deaths involving prescription drugs.

CONCLUSIONS

While individual drug substances might contribute to many deaths (e.g., fentanyl), polysubstance mortality is more common than single substance mortality. Multidimensional analyses integrating all drugs involved are useful to identify uncommon patterns of overdose and changing trends.

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.

Polysubstance use in young people accessing residential and day-treatment services for substance use: substance use profiles, psychiatric comorbidity and treatment completion

BACKGROUND AND AIMS

People with substance use disorders (SUDs) frequently present to treatment with polysubstance use and mental health comorbidities. Different combinations of substance use and mental health problems require different treatment approaches. Our study aimed to: (i) identify the shared substance use classes among young people at treatment admission, (ii) determine which mental health symptoms, quality of life (QoL) and service types were associated with the identified substance use classes, and (iii) prospectively determine which substance use classes and service types were more likely to complete treatment.

DESIGN

Cross-sectional and prospective study using service and outcome data.

SETTING

Substance use treatment services in Queensland and New South Wales, Australia.

PARTICIPANTS

De-identified service and outcome measure data were extracted from the files of 744 clients aged 18-35 years (48% male) admitted into seven residential and four day-treatment programmes.

MEASUREMENTS

Substance use and severity among tobacco, alcohol, cannabis, cocaine, amphetamine-type stimulants, opioids, sedatives and inhalants. Other variables included: depression, anxiety, post-traumatic stress and psychotic symptoms, as well as QoL.

FINDINGS

Latent class analysis identified three polysubstance use classes: wide-ranging polysubstance users (WRPU; 22.45%), primary amphetamine users (56.45%) and alcohol and cannabis users (21.10%). The WRPU class had higher odds of psychotic symptoms than the alcohol and cannabis use class [odds ratio (OR) = 1.30; 95% confidence interval (CI) = 1.11-1.11]; and double the odds of residential programme enrolment than those in the amphetamine use class (OR = 2.35; 95% CI = 1.50-3.68). No other class differences on mental health or QoL variables were found. Clients enrolled in day-programmes had higher odds of completing treatment.

CONCLUSIONS

There appear to be high levels of polysubstance use among young people entering substance use treatment in Australia. Wide-ranging polysubstance users were more likely to report psychotic symptoms and be enrolled into a residential programme than primary amphetamine users and alcohol and cannabis users.

Risks and overdose responses: Participant characteristics from the first seven years of a national take-home naloxone program

BACKGROUND

In 2014, the Norwegian government funded a large-scale take-home naloxone (THN) program to address high overdose mortality rates. The aims of this study are to describe characteristics among persons trained to receive THN, describe actions taken following THN use at an overdose event and to explore factors associated with naloxone use.

METHODS

This was a prospective cohort study of individuals who received THN from 2014 to 2021. Descriptive characteristics were collected at initial training. When returning for refill, participants reported on their previous naloxone use. In a multivariable logistic regression model exploring associations with naloxone use: gender, age, opioid use history, concomitant drug use, injecting, history of experienced or witnessed overdose were included.

RESULTS

In total, 3527 individuals were included in this study. There were 958 individuals who returned for refills 2303 times. Most participants were male (63.6%), with a history of opioid use (77.5%). Those who reported naloxone use were more likely to have a history of opioid use (aOR= 4.1; 95% CI=2.77,6.1), were younger (aOR=0.98; 95% CI=0.97,0.99) and had witnessed overdoses (aOR=3.3; 95% CI=1.98,5.34). Among current opioid users, the odds were higher for injectors (aOR=1.57; 95% CI=1.18,2.1). Naloxone use was reported 1282 times. Additional actions such as waking the person and calling the ambulance were frequently reported. Survival was reported in almost all cases (94%).

CONCLUSION

People who use drugs are a suitable target group for THN-programs, as they seem to be willing and capable to reverse overdoses effectively. Given their personal risk factors for overdosing, recipients will likely also benefit from overdose prevention education.

Poisoning with central stimulant drugs: an observational study from Oslo, Norway

Background

The use of central stimulant drugs causes significant morbidity. We describe poisonings with central stimulant drugs and compare the different central stimulants concerning combinations with other drugs, treatment, and clinical course. 

Methods

Patients presenting from 1 October 2013 to 31 March 2016 with poisoning related to the recreational use of central stimulant drugs were retrospectively included at a primary care emergency outpatient clinic and at a hospital emergency department in Oslo, Norway. Diagnosis of toxic agents was mainly based on the clinical assessment of the doctor treating the patient. Amphetamine and methamphetamine were co-categorized as amphetamine.

Results

Among the 1131 cases of acute poisoning with central stimulant drugs at the outpatient clinic, amphetamine was involved in 808 (71.4%), cocaine in 252 (22.3%) methylenedioxymethamphetamine (MDMA) in 104 (9.2%), and methylphenidate in 13 (1.1%). Among the 211 cases at the hospital, amphetamine was involved in 167 (79.1%), cocaine in 60 (28.4%), and MDMA in 38 (18.0%). Amphetamine was frequently combined with opioids (40.1% at the outpatient clinic and 41.9% at the hospital) and benzodiazepines (28.3% and 45.5%), while MDMA often was combined with ethanol (64.4% and 71.1%), as was cocaine (62.7% and 61.7%). Sedation was given in 5.2% and 38.4% of cases, naloxone in 9.4% and 37.0%, and flumazenil in 0.1% and 28.0%. In total, 16.5% of the cases at the outpatient clinic were transferred to a hospital for medical review and 8.5% to a psychiatric hospital. Among the hospital patients, 92.9% were admitted to intensive care.

Conclusion

Amphetamine was the most common central stimulant drug involved in acute poisoning in Oslo, often combined with opioids and benzodiazepines.

For whom the bell tolls: psychopathological and neurobiological correlates of a DNA methylation index of time-to-death

Psychopathology is a risk factor for accelerated biological aging and early mortality. We examined associations between broad underlying dimensions of psychopathology (reflecting internalizing and externalizing psychiatric symptoms), PTSD, and age-adjusted GrimAge ("GrimAge residuals"), a DNA methylation biomarker of mortality risk relative to age. We also examined neurobiological correlates of GrimAge residuals, including neurocognitive functioning, blood-based biomarkers (of inflammation, neuropathology, metabolic disease), and cortical thickness. Data from two independent trauma-exposed military cohorts (n = 647 [62.9% male, Mage = 52], n = 434 [90% male, Mage = 32]) were evaluated using linear regression models to test associations between GrimAge residuals, psychopathology, and health correlates. Externalizing psychopathology significantly predicted GrimAge residuals in both cohorts (ps < 0.028). PTSD predicted GrimAge residuals in the younger (p = 0.001) but not the older cohort. GrimAge residuals were associated with several neurobiological variables available in the younger cohort, including cognitive disinhibition (padj = 0.021), poorer memory recall (padj = 0.023), cardiometabolic pathology (padj < 0.001), oxidative stress (padj = 0.003), astrocyte damage (padj = 0.021), inflammation (C-reactive protein: padj < 0.001; IL-6: padj < 0.001), and immune functioning (padj < 0.001). A subset of inflammatory and neuropathology analytes were available in the older cohort and showed associations with GrimAge residuals (IL-6: padj < 0.001; TNF-α: padj < 0.001). GrimAge residuals were also associated with reduced cortical thickness in right lateral orbitofrontal cortex (padj = 0.018) and left fusiform gyrus (padj = 0.030), which are related to emotion regulation and facial recognition, respectively. Psychopathology may be a common risk factor for elevated mortality risk. GrimAge could help identify those at risk for adverse health outcomes and allow for early disease identification and treatment.

Who is using take-home naloxone? An examination of supersavers

Background

As the opioid overdose crisis persists and take-home naloxone (THN) programmes expand, it is important that the intervention is targeted towards those most likely to use it. We examined THN program participants to 1) describe those that return for refills, specifically those that reported multiple use (supersavers), and 2) to examine what rescuer characteristics were associated with higher rates of THN use.

Methods

This study included a cohort of consenting THN recipients from June 2014–June 2021 who completed initial and refill questionnaires from a widespread program in Norway. Age, gender, number of witnessed and experienced overdoses were assessed for associations with higher reported rates of THN use. ‘Supersavers’ reported 3 or more THN uses.

Results

A total of 1054 participants returned for a THN refill during the study period. Of these, 558 reported their last THN to have been used on an overdose. Supersavers (those that reported 3 or more THN uses) were younger, primarily reported current opioid use, and had witnessed higher rates of overdoses at the time of initial training when compared to non-supersavers (those that reported 0–2 THN uses).

Conclusions

THN programs should continue to emphasize and prioritize THN for people actively using drugs, particularly those who have witnessed overdoses previously.

Polydrug Use and Co-occurring Substance Use Disorders in a Respondent Driven Sampling of Cocaine Base Paste Users in Santiago, Chile

We characterized substance use patterns and co-occurring substance use disorders among active cocaine base paste (CBP) users in Santiago, Chile using data from respondent-driven sampling (RDS) in three areas of Metropolitan Santiago. Recruitment began with nine seeds, reaching 398 active CBP users (18% women; mean age 37.7 years), defined as persons consuming CBP at least twice per week in the last three months. Population proportions and uncertainty were estimated accounting for individuals' social network and homophily. The median CBP age of initiation was 21 years, and the median number of years using CBP was 7 for women and 15 for men. The median days of use in the past month was 25 days, with a median of 56 doses per week. The proportion of monthly income spent on CBP was 65%. The prevalence of substance use disorders (SUDs) were: 98% for CBP, 67% for alcohol, 60% for marijuana, and 41% for cocaine hydrochloride. Heavy polydrug use patterns and co-occurring SUDs are frequent among active CBP users in the metropolitan area of Santiago. Traditional surveillance strategies may have underestimated polysubstance use and co-occurring SUDs in active CBP users. RDS proved to be a feasible methodology that could be effectively used for substance use surveillance among hard-to-reach populations.

Morbidity and mortality in schizophrenia with comorbid substance use disorders

OBJECTIVE

Schizophrenia is highly comorbid with substance use disorders (SUD) but large epidemiological cohorts exploring the prevalence and prognostic significance of SUD are lacking. Here, we investigated the prevalence of SUD in patients with schizophrenia in Finland and Sweden, and the effect of these co-occurring disorders on risks of psychiatric hospitalization and mortality.

METHODS

45,476 individuals with schizophrenia from two independent national cohort studies, aged <46 years at cohort entry, were followed during 22 (1996-2017, Finland) and 11 years (2006-2016, Sweden). We first assessed SUD prevalence (excluding smoking). Then, we performed Cox regression on risk of psychiatric hospitalization and all-cause and cause-specific mortality in SUD compared with those without SUD.

RESULTS

The prevalence of SUD ranged from 26% (Finland) to 31% (Sweden). Multiple drug use (n = 4164, 48%, Finland; n = 3268, 67%, Sweden) and alcohol use disorders (n = 3846, 45%, Finland; n = 1002, 21%, Sweden) were the most prevalent SUD, followed by cannabis. Any SUD comorbidity, and particularly multiple drug use and alcohol use, were associated with 50% to 100% increase in hospitalization (aHR any SUD: 1.53, 95% CI = 1.46-1.61, Finland; 1.83, 1.72-1.96, Sweden) and mortality (aHR all-cause mortality: 1.65, 95% CI = 1.50-1.81, Finland; 2.17, 1.74-2.70, Sweden) compared to individuals without SUD. Elevated mortality risks were observed especially for suicides and other external causes. All results were similar across countries.

CONCLUSION

Co-occurring SUD, and particularly alcohol and multiple drug use, are associated with high rates of hospitalization and mortality in schizophrenia. Preventive interventions should prioritize detection and tailored treatments for these comorbidities, which often remain underdiagnosed and untreated.

National trends in substance use treatment admissions for opioid use disorder among adults experiencing homelessness

OBJECTIVE

People experiencing homelessness (PEH) have high rates of substance use, and homelessness may be an important driver of health disparities in the opioid overdose epidemic. However, few studies focus on homelessness among the opioid use disorder (OUD) treatment population. We examine national-level trends in substance use treatment admissions among PEH with OUD.

METHODS

This study used data from first-time treatment admissions in the United States from the Treatment Episode Data Set: Admissions (TEDS-A) to examine characteristics and trends of adults experiencing homelessness who entered state-licensed substance use treatment programs for OUD from 2013 to 2017. We used chi-squared analyses to examine changes in characteristics of this population over time and logistic regression to assess characteristics associated with receipt of medications for opioid use disorder (MOUD) among PEH.

RESULTS

Among all adults with OUD entering specialty treatment from 2013 to 2017, 12.5% reported experiencing homelessness. Compared to individuals not experiencing homelessness, PEH were more likely to be male, inject opioids, use cocaine or methamphetamine, and enter into residential detoxification treatment. PEH were less likely to enter outpatient treatment or receive MOUD. From 2013 to 2017, significant increases occurred in the proportion of PEH who had co-occurring psychiatric problems and used methamphetamines. Over time, treatment type shifted significantly from residential detoxification to outpatient treatment. Receipt of MOUD increased among PEH over time (13.7% to 25.2%), but lagged behind increases among individuals not experiencing homelessness. Among PEH, being older was associated with receiving MOUD, while concurrent methamphetamine use [adjusted odds ratio (AOR) 0.63; 95% CI 0.58, 0.69] and living in the southern United States (AOR 0.27; 95% CI 0.25, 0.30) were associated with not receiving MOUD.

DISCUSSION

The proportion of PEH with OUD who receive medications as part of treatment increased over time, but three quarters of PEH entering treatment still do not receive this highest standard in evidence-based care. The sharp increase observed in concomitant methamphetamine use in this population is concerning and has implications for treatment.

Characteristics and risk of incarceration among "hard-to-reach" people who use drugs: A five-year prospective cohort study combining self-reports and registry data

BACKGROUND

Incarcerations are associated with an increased risk of morbidity and mortality among people who use drugs (PWUD). In a sample of 884 PWUD, we examine and estimate the risk of incarcerations (i.e., number, duration, and most serious offense).

METHODS

In this prospective cohort study, PWUD were recruited from street- and low-threshold services in seven Norwegian cities in 2013 (Sept-Nov), and followed through the Correctional Service Registry until 20.12.2018. The risk of incarceration during follow-up was examined with multivariable logistic (no incarceration vs. at least one) and multinomial regression models ("no incarcerations", vs. "1″, "≥2″), while accounting for gender, age, homelessness/shelter use, opioid substitution treatment, illegal income sources, injecting behaviours, previous incarcerations, and recruitment city.

RESULTS

During follow-up, there were in total 662 incarceration episodes, and 44.7% of the participants were incarcerated at least once. Overall, 37.5% of those incarcerated had at least one episode due to a drug offense. The average incarceration duration was 65.2 days with 3.5% of the episodes lasting ≥one year. Gender (male), homelessness/shelter use, illegal income sources, injecting stimulants, and previous incarcerations increased the odds of incarceration, while older age decreased the odds. Gender (male), younger age, self-reported theft or theft and dealing, injecting stimulants or heroin and stimulants and previous incarcerations increased the risk of multiple incarcerations.

CONCLUSION

In a five-year prospective study of PWUD, incarcerations were common, and short-term sentences and recidivism were the norm. This is of concern as incarcerations add to an already elevated morbidity and mortality risk in this population.

Association between discharges against medical advice and readmission in patients treated for drug injection-related skin and soft tissue infections

BACKGROUND

The prevalence of injection drug use (IDU)-related skin and soft tissue infections (SSTI) in Philadelphia has been steadily increasing since 2013. Patients seeking treatment for these infections are more likely to be discharged against medical advice (AMA), increasing the likelihood that they will end antibiotic treatment prematurely and require additional medical interventions.

METHODS

The research team performed a nested case-control study using the Pennsylvania Health Care Cost Containment Council database for Philadelphia residents hospitalized for SSTI and substance use-related diagnoses between 2013 and 2018. The primary outcome was readmission in the same or following quarter. The study examined the impact of discharge AMA on readmission along with clinical characteristics including diagnoses for anxiety, bipolar disorder, depression, schizophrenia, diabetes, and polydrug use.

RESULTS

There were 8265 hospitalizations for IDU-related SSTI and 316 (6%) were readmitted to the hospital at least once in the same or following quarter. In total, 23.4% of cases and 13% of controls left AMA. In the final multivariable regression model, AMA discharge (AOR 2.04, 95% CI 1.46-2.86), anxiety (AOR 1.44, 95% CI 1.01-2.05), diabetes (AOR 2.02, 95% CI 1.46-2.81), and polydrug use (AOR 2.11, 95% CI 1.52-2.92) were associated with higher odds of readmission.

CONCLUSIONS

Our study demonstrates that readmissions for IDU-related SSTI are associated with recent discharge AMA. As IDU-related SSTI and polydrug use continue to rise, premature antibiotic treatment completion will impact more people, leading to worse health outcomes and additional strain on the health care system.

Poly-prescription drug misuse across the life course: Prevalence and correlates across different adult age cohorts in the U.S

BACKGROUND

Most research on prescription drug misuse (PDM) focuses on the misuse of specific classes of psychoactive prescription drugs among adolescents or young adults. The current research addressed important gaps in the literature by assessing poly-prescription drug misuse (poly-PDM), the misuse of more than one class of psychoactive prescription drug, across different adult age cohorts.

METHODS

We used the 2015-2018 National Survey on Drug Use and Health to examine the prevalence of past-year poly-PDM and specific combinations of PDM. Multinomial logistic regression was used to identify demographic, health-related factors, and substance use behaviors that were significantly associated with poly-PDM.

RESULTS

The prevalence of poly-PDM decreases with age and is common among individuals who engage in PDM. Slightly more than one in four respondents in age cohorts 18-25 (31.66%, 95% CI = 30.35, 33.00) and 26-34 (29.92%, 95% CI = 25.82, 30.12) who engage in PDM, misused more than one class of prescription drug. Additionally, poly-PDM was identified as a high-risk type of PDM as roughly 60% of adults younger than 65 who endorse poly-PDM reported having a substance use disorder (SUD). While certain characteristics (i.e., race/ethnicity, marital status, depression, suicidal ideation, illegal drug use, and SUD) were consistently associated with poly-PDM across age cohorts, other characteristics (i.e., sexual identity, income, and justice involvement) varied across age cohorts. Finally, a comparison of poly-PDM to single PDM showed, in all age cohorts, that having an SUD was associated with an increased likelihood of poly-PDM, while Black adults were less likely than whites to report poly-PDM.

CONCLUSIONS

By identifying prevalence and correlates of poly-PDM across adult age cohorts, the current research has significant implications. Understanding stability and heterogeneity in the characteristics associated with poly-PDM should inform interventions, identify at-risk groups, and shape public health approaches to dealing with high-risk substance use behavior.

Clinical symptoms and personality traits predict subpopulations of treatment-seeking substance users

BACKGROUND

The heterogeneity of treatment-seeking substance users represents a challenge, as most studies include participants having problems with specific substances or merge polysubstance users into the same category without considering differences between profiles. Considering the inconsistent literature on predictors of treatment outcomes, this study aimed to identify subpopulations of individuals with substance use disorders (SUDs) and analyze the association among class membership, previous relapses, and treatment retention.

METHODS

The study recruited a total of 159 participants (mean age = 40.60, SD = 8.70; 85.5% males) from two treatment facilities (outpatient daycare and inpatient residential centers). The baseline assessment gathered lifetime and current substance use, and personality and psychopathology measures. The study performed a latent class analysis to identify subpopulations of substance users and explored predictors of class membership using a multinomial regression analysis.

RESULTS

The study found six different classes of substance users based on their diagnosis and pattern of substance use: class 1 (6.92% of participants): individuals with cannabis as primary substance, alcohol/cocaine as secondary substance and additional use of stimulants or other drugs; class 2 (30.82%): cocaine as primary substance, alcohol as secondary and additional cannabis use; class 3 (20.13%): alcohol as primary substance, cocaine as secondary and additional cannabis use; class 4 (17.61%): cocaine as primary substance, cannabis as secondary and additional alcohol/other drugs use; class 5 (16.35%): alcohol as primary and cannabis as secondary substance; class 6 (8.18%): heroin as primary substance, cocaine as secondary and additional alcohol use. Several traits and clinical symptoms predicted distinct class memberships. Participants pertaining to class 6 presented the highest number of relapses (M = 2.54, SD = 1.56).

CONCLUSIONS

These results have several clinical implications. Belonging to class 6 was associated with a greater number of previous relapses. Also, specific psychopathological symptoms and personality traits may impact SUD treatment response, which may help clinicians to guide initial assessment and treatment allocation.

Peer-assisted injection as a harm reduction measure in a supervised consumption service: a qualitative study of client experiences

Background

Peer assistance is an emerging area of study in injection drug use. When Canada’s first supervised consumption site (SCS) opened in 2003 in Vancouver, Canada, clients were prohibited from injecting their peers; only recently has this practise been introduced as a harm reduction measure at these sites. In 2018, Health Canada granted federal exemption to allow peer-assisted injection at certain SCS sites, under the Controlled Drugs and Substances Act. Literature pertaining to peer-assisted injection addresses several topics: interpersonal relationships between the injection provider and recipient; the role of pragmatism; trust and expertise; and gender relations.

Methods

In this qualitative study, participants (n = 16) were recruited to be interviewed about their experiences in a peer-assisted injection program (PAIP) at one SCS regulated by Health Canada. Interview data were transcribed and thematically analyzed. Quantitative administrative data were used to provide context and to describe the study population, comprised of people in the PAIP (n = 248).

Results

PAIP clients made up 17.4% of all SCS clients. PAIP clients were more likely to be female and Indigenous. Injection providers expressed being moved by compassion to help others inject. While their desire to assist was pragmatic, they felt a significant burden of responsibility for the outcomes. Other prominent factors related to the injection provider-recipient relationship were social connection, trust, safety, social capital, and reciprocity. Participants also made suggestions for improving the PAIP which included adding more inhalation rooms so that if someone was unable to inject they could smoke in a safe place instead. Additionally, being required by law to divide drugs outside of the SCS, prior to preparing and using in the site, created unsafe conditions for clients.

Conclusions

Regular use of the SCS, and access to its resources, enabled participants to lower their risk through smoking and to practice lower-risk injections. At the federal level, there is considerable room to advocate for allowing clients to divide drugs safely within the SCS, and to increase capacity for safer alternatives such as inhalation.

Injecting Alone is More Common among Men, Frequent Injectors and Polysubstance Users in a Sample of People Who Inject Drugs

Injecting alone increases the risk of a fatal overdose. We examined the extent of such behavior in a sample of people who inject drugs (PWID) and the typical characteristics of those injecting alone at least once during the past four weeks. A cross-sectional study. PWID recruited from the street and from low-threshold services in seven Norwegian cities in September 2017 (n = 359). Associations between characteristics and injecting alone were examined using logistic regression analysis. The independent variables were gender (female/male), age, having received overdose-prevention education (no/yes), and, in the past four weeks; homelessness/shelter use (no/yes), in opioid substitution treatment (no/yes), injecting ≥ four days a week (no/yes), and substances injected (opioids only/opioids and other/other only/central stimulants (CS) only/CS and other/CS and opioids/CS, opioids and other). The adjusted odds ratios (aOR) and 95% Confidence Intervals (CI) were reported. Of the 359 PWID, 84.4% reported having injected alone. Males were more likely than females to inject alone (aOR = 1.88 95% CI 1.00-3.54). Furthermore, those injecting frequently (aOR = 1.99 95% CI 1.02-3.86) and those injecting multiple substances (CS, opioids and other) (aOR = 2.94 95% CI 1.01-8.58) were more likely to inject alone compared to those injecting less frequently and opioids only. Although not statistically significant, the effect sizes in the logistic regression models suggest that polysubstance use may be driven by CS use. Injecting alone was common in our sample of PWID, and male gender, frequent injecting and polysubstance injecting were associated with this behavior.

Commentary: Suggesting Shinrin-yoku (forest bathing) for treating addiction

Shinrin-yoku ('') (i.e., forest bathing), a Japanese wellbeing practice, aims to harmonise a person with a forest by bathing in the forest mindfully using our five senses (Miyazaki, 2018). Practitioners can choose whatever they like to focus on in the forest: different colours of leaves, the sounds of streams, or the warmth of sunshine beaming between leaves. Since the birth of this practice in 1982, shinrin-yoku has been widely used in the Japanese clinical fields (Hansen, Jones, & Tocchini, 2017). Recently, this healing practice has received attention from healthcare practitioners and researchers worldwide (Wen, Yan, Pan, Gu, & Liu, 2019). In this commentary, we will discuss limitations of the current shinrin-yoku research, and how future research can be conducted to appraise the effects of shinrin-yoku on addiction.

COVID-19 survey among people who use drugs in three cities in Norway

BACKGROUND

Little is known regarding what people who use drugs (PWUD) know about COVID-19 related issues and changes in the drug market due to COVID-19. We therefore conducted a survey to explore these issues.

METHODS

In a cross-sectional study, we interviewed 226 PWUD from three Norwegian cities in May/June 2020. Participants completed an interview-administrated questionnaire. Three separate multiple binary logistic regression models were estimated with the outcomes (no/yes): 1. Familiarity with COVID-19 symptoms, 2. Awareness of COVID-19 services tailored towards PWUD and, 3. Willingness to take a COVID-19 test.

RESULTS

The mean age was 44.1 years and 73 % were males. Fifty-four percent were injectors, and heroin/other opioids (35.8 %) and cocaine/amphetamine (25.2 %) were the most common main drugs used. Overall, 54.9 % were in opioid maintenance treatment (OMT). The majority (65.9 %) stated they knew the COVID-19 symptoms. Almost all the participants (91.2 %) reported they would take a COVID-19 test if experiencing relevant symptoms. The majority (63.7 %) were not aware of COVID-19 services available to PWUD. OMT patients were more likely to be familiar with COVID-19 symptoms (aOR = 3.4, 95 % CI 1.7; 6.8), and to be aware of COVID-19 services (aOR = 2.7, 95 % CI 1.1; 6.3). Overall, 35.4 % reported reduced drug availability, mainly for tranquilizers, while 61.5 % reported increased drug prices, mainly for cannabis.

CONCLUSION

Drug treatment may play an important role in COVID-19 prevention, as those in OMT were more likely to be aware of symptoms and of availability of services.

Patterns, contexts, and motivations for polysubstance use among people who inject drugs in non-urban settings in the U.S. Northeast

BACKGROUND

Polysubstance use (i.e., using ≥2 psychoactive substances concomitantly) is associated with increased morbidity and mortality and complicates drug treatment needs among people who inject drugs (PWID). We explored patterns, contexts, motivations, and perceived consequences of polysubstance use among PWID in small cities and towns in the U.S. Northeast.

METHODS

Between October 2018 and March 2019, we conducted semi-structured interviews with 45 PWID living outside of the capital cities of Rhode Island and Massachusetts recruited online and through community-based organizations. Written transcripts were coded inductively and deductively using a team-based approach and analyzed thematically.

RESULTS

All participants reported recent polysubstance use, with most using five or more classes of substances in the past three months. Polysubstance use often followed long personal drug use histories (i.e., years or decades of occasional drug use). Reasons for polysubstance use included obtaining synergistic psychoactive effects as a result of mixing drugs (i.e., using drugs to potentiate effects of other drugs) and managing undesirable effects of particular drugs (e.g., offsetting the depressant effects of opioids with stimulants or vice-versa). Polysubstance use to self-medicate poorly managed physical and mental health conditions (e.g., chronic pain, anxiety, and depression) was also reported. Inadequately managed cravings and withdrawal symptoms prompted concomitant use of heroin and medications for opioid use disorder, including among individuals reporting cocaine or crack as their primary "issue" drugs. Polysubstance use was perceived to increase overdose risks and to be a barrier to accessing healthcare and drug treatment services.

CONCLUSION

Healthcare services and clinicians should acknowledge, assess, and account for polysubstance use among patients and promote harm reduction approaches for individuals who may be using multiple drugs. Comprehensive healthcare that meets the social, physical, mental health, and drug treatment needs of PWID may decrease the perceived need for polysubstance use to self-medicate poorly managed health conditions and symptoms.

Latent classes of lifetime drug use disorder in national epidemiological survey on alcohol and related conditions - III

AIMS/BACKGROUND

People diagnosed with multiple drug use disorders are high-risk subpopulations, but changes in diagnostic classification and drug use prevalence mean patterning of drug use disorders has changed in the past decade. We analyzed comorbidity patterns of lifetime drug use disorder in a general population sample.

DESIGN

Using latent class analysis, we derived lifetime drug use disorder classes based on dichotomous indicators of sedative, cannabis, opioid, cocaine, stimulant, hallucinogen, inhalant/solvent, club drug, heroin, and other drug use disorders in the National Epidemiologic Survey on Alcohol and Related Conditions-III (n = 36,309). Multinomial models assessed associations between sociodemographic and clinical correlates and latent class status.

RESULTS

Four latent classes of lifetime substance use disorder were identified: A very low risk class, a class with high opioid, sedative and heroin comorbidity, a class based on cocaine and stimulant comorbidity, and class with high likelihood of multiple lifetime drug use disorders. All higher risk classes were associated with higher risk of lifetime personality disorder and mood disorder. Conduct disorder was also associated with higher risk, but level of risk varied by class. Opioid and sedative class was associated with higher odds of lifetime eating disorder diagnosis.

CONCLUSIONS

Comorbidity of drug use disorders is associated with a range of lifetime mental health disorder diagnoses. Unlike previous research, we did not identify a cannabis use class, possibly due to changes in diagnostic criteria and cannabis prevalence rates.

Opioid use disorder

Opioid use disorder (OUD) is a chronic relapsing disorder that, whilst initially driven by activation of brain reward neurocircuits, increasingly engages anti-reward neurocircuits that drive adverse emotional states and relapse. However, successful recovery is possible with appropriate treatment, although with a persisting propensity to relapse. The individual and public health burdens of OUD are immense; 26.8 million people were estimated to be living with OUD globally in 2016, with >100,000 opioid overdose deaths annually, including >47,000 in the USA in 2017. Well-conducted trials have demonstrated that long-term opioid agonist therapy with methadone and buprenorphine have great efficacy for OUD treatment and can save lives. New forms of the opioid receptor antagonist naltrexone are also being studied. Some frequently used approaches have less scientifically robust evidence but are nevertheless considered important, including community preventive strategies, harm reduction interventions to reduce adverse sequelae from ongoing use and mutual aid groups. Other commonly used approaches, such as detoxification alone, lack scientific evidence. Delivery of effective prevention and treatment responses is often complicated by coexisting comorbidities and inadequate support, as well as by conflicting public and political opinions. Science has a crucial role to play in informing public attitudes and developing fuller evidence to understand OUD and its associated harms, as well as in obtaining the evidence today that will improve the prevention and treatment interventions of tomorrow.

Mortality and causes of death among people suspected of driving under the influence and testing positive for multiple substances

Aims: Understanding the mortality of drug users using multiple substances is helpful in preventing the harmful effects of polydrug use. We examined overall and cause-specific mortality and differences in mortality based on social background among people suspected of driving under the influence and testing positive for multiple substances (DUIMS) compared with the general Finnish population. Methods: Register data from 785 DUIMS during 2003-2006 were studied, with a reference population (n = 25,381) drawn from the general Finnish population. The effect of DUIMS on all-cause and cause-specific mortality was estimated using a Poisson regression model. Results: DUIMS had an increased risk of death compared with the general population (MRR 5.3, 95% CI 4.2-6.6). The most common causes of death in DUIMS were poisonings (37.9%) and suicides (13.6%), whereas in the reference population these were cardiovascular diseases (30.8%) and cancer (26.6%). The cause-specific risk of death among DUIMS was higher in all observed causes of death, except for cancer. The effect of DUIMS on mortality was modified by age, employment status and marital status; DUIMS was associated with an elevated risk of death especially in younger age groups and in singles. Conclusions: DUIMS indicates higher mortality, and DUIMS' profiles in causes of death differ from the general population. Elevated risk for, for instance, suicidal, accidental and violent death among those using multiple substances highlights the need to also pay attention to causes of death other than poisoning/overdose.

Polydrug use disorders in individuals with opioid use disorder

BACKGROUND

Understanding the association of polydrug use disorders (PUD) with psychosocial and clinical factors is essential for the treatment of individuals with opioid use disorder (OUD). The aim of this study is to examine whether there is an association between childhood maltreatment, mood disorders, anxiety disorders, personality disorders, or posttraumatic stress disorder (PTSD) and PUD in individuals with OUD.

METHODS

We used data from 356 individuals with OUD in the past 12 months from a nationally representative database in the United States. PUD patients were classified into two groups: a group with additional one substance disorder (OUD + 1) and that with two or more additional substance disorders (OUD + 2). We conducted multivariate logistic regression to predict the PUD status, after adjustment for confounders including childhood maltreatment.

RESULTS

Among all individuals, 57.3% were polydrug users (n = 204) and 42.7% were not (n = 152). There was a high prevalence of childhood maltreatment in both groups, ranging from 16.1% to 59.5%, but the difference was not statistically significant. After adjustment for confounders, we found an association between past-year PTSD and OUD + 2 (odds ratio: 3.98; 95% confidence interval: 1.15-13.72; p = 0.03) but not with OUD + 1.

CONCLUSION

PTSD is highly prevalent in individuals with OUD using multiple substances and could influence PUD. We recommend screening for PTSD in cases of PUD. Future studies should evaluate the effect of PTSD treatment on PUD.

Rising role of prescription drugs as a portal to injection drug use and associated mortality in Baltimore, Maryland

INTRODUCTION

Prescription drug abuse is a major public health problem in rural and suburban areas of the United States, however its emergence in large urban settings with endemic injection drug use remains understudied. We examined temporal trends in injection drug use initiation and mortality among people who inject drugs (PWID) in Baltimore, Maryland.

METHODS

Data were derived from the baseline assessment of PWID enrolled in a community-based cohort study with longitudinal follow-up for mortality assessment. PWID were recruited from 2005-2008 (N = 1,008) and 2015-2018 (N = 737). We compared characteristics by birth cohort (before/after 1980) and type of drug initiated (prescription opioids, prescription non-opioids, non-injection illicit drugs, or injection drugs). We calculated standardized mortality ratios (SMR) using the US general population as the reference.

RESULTS

PWID born after 1980 were more likely to initiate drug use with prescription opioids and non-opioids and had higher levels of polysubstance prior to injection initiation, compared to individuals born before 1980. Overall mortality was high: 2.59 per 100 person-years (95% CI: 2.27-2.95 per 100 person-years). Compared to the US population, the highest SMRs were observed among participants between 40-44 years of age, with especially high mortality among women in this age group (SMR:29.89, 95% CI: 15.24-44.54).

CONCLUSIONS

Mirroring national trends, the profile of PWID in Baltimore has changed with increased prescription drug abuse and high levels of polysubstance use among younger PWID. Interventions need to reach those using prescription drugs early after initiation of use in order to reduce transition to injecting. Urgent attention is warranted to address premature mortality, particularly among middle-aged and female PWID.

Polydrug use patterns and their impact on relapse among heroin-dependent patients in Shanghai, China

AIMS

To describe the polysubstance use patterns of heroin-dependent patients and to understand the impact of polysubstance use patterns on relapse during the 5 years after completing compulsory rehabilitation programmes.

DESIGN

In this secondary analysis, the baseline data of 503 heroin-dependent patients were linked with their 5-year follow-up data from official records.

SETTING

Four compulsory rehabilitation centres in Shanghai, China.

PARTICIPANTS

A total of 564 heroin-dependent patients who were discharged from Shanghai compulsory rehabilitation facilities in 2007 and 2008 were recruited. Among these, 503 patients with available follow-up records were included in this analysis.

MEASUREMENTS

The baseline measurements included the Addiction Severity Index, the Temperament and Character Inventory and the Medical Outcomes Study Social Support Scale. Relapses after discharge from the compulsory rehabilitation centres were extracted monthly from the official electronic record system. Latent class analysis was used to identify different polysubstance use patterns. Associations between the identified latent classes and heroin use and the factors related to relapse during the 5-year follow-up were analysed with the Cox regression model.

FINDINGS

Three latent classes were identified in this cohort: (1) alcohol polydrug users (APU; 13.7%), (2) low polydrug users (LPU; 76.5%) and (3) amphetamine-type stimulant polydrug users (ASPU; 9.7%). During the 5-year follow-up, 298 heroin patients relapsed, and the three groups showed different relapse rates (ASPU 69.4 versus LPU 60.5 versus APU 44.9%, P = 0.02). The average durations of abstinence for the three groups differed (ASPU 31.27 ± 3.41 months versus LPU 36.77 ± 1.19 months versus APU 42.46 ± 2.81 months, P = 0.02). Multivariate Cox regression analyses found that the LPU [hazard ratio (HR) = 1.63, 1.06-2.51] and ASPU (HR = 2.10, 1.24-3.56) classes were positively associated with the risk of heroin relapse.

CONCLUSION

Polydrug use patterns differ among heroin-dependent patients in compulsory rehabilitation programmes in China. A history of polydrug use may predict heroin relapse risk among patients in those compulsory rehabilitation programmes.

Naloxone distribution and possession following a large-scale naloxone programme

AIMS

To examine uptake following a large-scale naloxone programme by estimating distribution rates since programme initiation and the proportion among a sample of high-risk individuals who had attended naloxone training, currently possessed or had used naloxone. We also estimated the likelihood of naloxone possession and use as a function of programme duration, individual descriptive and substance use indicators.

DESIGN

(1) Distribution data (June 2014-August 2017) and date of implementation for each city and (2) a cross-sectional study among a sample of illicit substance users interviewed September 2017.

SETTING

Seven Norwegian cities.

PARTICIPANTS

A total of 497 recruited users of illegal opioids and/or central stimulants.

MEASUREMENTS

Primary outcomes: naloxone possession and use. Random-intercepts logistic regression models (covariates: male, age, homelessness/shelter use, overdose, incarceration, opioid maintenance treatment, income sources, substance use indicators, programme duration).

FINDINGS

Overall, 4631 naloxone nasal sprays were distributed in the two pilot cities, with a cumulative rate of 495 per 100 000 population. In the same two cities, among high-risk individuals, 44% and 62% reported current naloxone possession. The possession rates of naloxone corresponded well to the duration of each participating city's distribution programme. Overall, in the six distributing cities, 58% reported naloxone training, 43% current possession and 15% naloxone use. The significant indicators for possession were programme duration [adjusted odds ratios (aOR) = 1.44, 95% confidence interval (CI = 0.82-2.37], female gender (aOR = 1.97, 95% CI = 1.20-3.24) and drug-dealing (aOR = 2.36, 95% CI = 1.42-3.93). The significant indicators for naloxone use were programme duration (aOR = 1.49 95%, CI = 1.15-1.92), homelessness/shelter use (aOR = 2.06, 95% CI = 1.02-4.17), opioid maintenance treatment (OMT) (aOR = 2.07, 95% CI = 1.13-3.78), drug-dealing (aOR = 2.40, 95% CI = 1.27-4.54) and heroin injecting (aOR = 2.13, 95% CI = 1.04-4.38).

CONCLUSIONS

A large-scale naloxone programme in seven Norwegian cities with a cumulative distribution rate of 495 per 100 000 population indicated good saturation in a sample of high-risk individuals, with programme duration in each city as an important indicator for naloxone possession and use.