The Polysubstance Overdose-Death Crisis

Consumption of oxycodone prevents oxytocin from attenuating alcohol intake in rats

Alcohol and opioid polysubstance use (PSU) is common and often accompanied by higher trait anxiety. Oxytocin decreases anxiety, alcohol- and opioid-seeking and -taking but has not been assessed in the context of PSU. Here we developed a rat model of sequential oxycodone and alcohol PSU to examine the relationship between anxiety, alcohol and oxycodone intake, and the efficacy of systemic oxytocin to attenuate alcohol intake. Male and female Sprague-Dawley rats were assessed for baseline anxiety-like behavior using acoustic startle and the elevated plus maze (EPM). Rats were then given 2-bottle choice access to oxycodone and/or water for 6-hr/day for 7 days, followed by 2-bottle choice access to alcohol (20% v/v) and/or water for five 24-hr sessions across 10 days. Next, monosubstance (oxycodone- or alcohol-alone) rats continued to have access to only one substance/day while PSU rats had access to oxycodone and water for 3-hr, followed by alcohol and water for 6-hr. After 12 days, rats were tested in the EPM 20 hours after alcohol access to examine withdrawal-related anxiety. Next, oxytocin (0, 0.3 or 1.0 mg/kg IP) was administered following the oxycodone/water session, 30 minutes prior to alcohol access. Rats received intragastric oxycodone (2 mg/kg) or water followed by intragastric alcohol (2 g/kg) and blood was collected to determine blood alcohol levels. Elevated baseline anxiety-like behavior was accompanied by reduced alcohol intake. Consumption of oxycodone did not alter alcohol intake but resulted in less anxiety-like behavior during withdrawal and prevented oxytocin from attenuating alcohol intake. Oxytocin (1 mg/kg) reduced alcohol intake in the alcohol-only condition, an effect that persisted for days after a single oxytocin administration. Rats that received oxycodone prior to non-contingent alcohol displayed higher blood alcohol levels than those that did not. These results support the necessity for the testing of medications for substance use in rodent models of PSU.

Using the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) to Predict Gambling Disorder Among U.S. College Students

The Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) screening tool has not previously been used to evaluate risk for gambling disorder (GD). We aimed to assess the level at which each specific substance involvement score (SSIS), measured by ASSIST, most optimally predicted GD among U.S. college students. Data were analyzed for 141,769 students from the National College Health Assessment (fall 2019-spring 2021) utilizing multivariable logistic regression models. Sensitivities and specificities were utilized to find optimal cutoffs that best identified those with GD, overall and by biological sex and age group. Lower threshold of substance risk related to prescription opioids, cocaine, and hallucinogens (all with SSIS cutoffs of 4) predicts gambling disorder compared to sedatives (SSIS cutoff of 19). Younger students had lower thresholds of substance risk predicting GD than older students for heroin, but for all other substance classifications students 25 years and older had lower thresholds of SSIS predicting GD than students 18-24 years old. This study aids in the understanding that substance use behavior may put students at risk for other addictive behaviors such as GD. This study is the first to utilize the ASSIST tool to predict GD among U.S. college students, extending its application beyond substance use disorders. The identification of optimal cutoffs for each SSIS provides a novel approach to concurrently screen for GD and substance use disorders. This unique contribution could enhance early detection and intervention strategies for GD in the college student population.

Risk factors for deaths of despair in England: An ecological study of local authority mortality data

Deaths of Despair (DoD) are socially patterned fatalities encompassing those attributable to drug and alcohol misuse and suicide. DoD occur much more frequently in socially deprived communities. This ecological study aimed to yield new knowledge on the spatial distribution of DoD, and socioeconomic factors that predict DoD risk in England. Via ICD-10 coding, deaths nationally during 2019-2021 were classified to non-overlapping categories of drug-related death, alcohol-specific death, and suicide. The proportion of DoD from each of these causes was calculated and age standardised DoD rates were generated for local authorities. A multivariable regression model for DoD risk was developed using 25 socioeconomic indicators. In 2019-2021, an estimated 46,200 people lost their lives due to DoD. Rates were higher in the North and in coastal areas (p < 0.001), ranging regionally from 25.1/100,000 (SD 6.3) in London to 54.7/100,000 (SD 9.5) in the North East. Alcohol-specific deaths were the largest contributor of DoD, accounting for 44.1% (95%CI 43.5-44.8%) of all such deaths. Living in the North, unemployment, White British ethnicity, living alone, economic inactivity, employment in elementary occupations, and living in urban areas were significantly associated with elevated DoD risk. DoD in England are spatially patterned, with northern regions experiencing a much higher burden of mortality from these avoidable causes. This study provides novel insights into the area-level factors associated with DoD in England. Potential ecological error is a key limitation.

Polysubstance mortality trends in White and Black Americans during the opioid epidemic, 1999-2018

BACKGROUND

Psychoactive drug combinations are increasingly contributing to overdose deaths among White and Black Americans. To understand the evolving nature of overdose crisis, inform policies, and develop tailored and equitable interventions, this study provides a comprehensive assessment of polysubstance mortality trends by race and sex during the opioid epidemic.

METHODS

We used serial cross-sectional US mortality data for White and Black populations from 1999 through 2018 to calculate annual age-adjusted death rates (AADR) involving any opioid, opioid subtypes, benzodiazepines, cocaine, psychostimulants, or combinations of these drugs, stratified by race and sex. Trend changes in AADR were analyzed using joinpoint regression models and expressed as average annual percent change (AAPC) during each period of the three waves of the opioid epidemic: 1999-2010 (wave 1), 2010-2013 (wave 2), and 2013-2018 (wave 3). Prevalence measures assessed the percent co-involvement of an investigated drug in the overall death from another drug.

RESULTS

Polysubstance mortality has shifted from a modest rise in death rates due to benzodiazepine-opioid overdoses among White persons (wave 1) to a substantial increase in death rates due to illicit drug combinations impacting both White and Black populations (wave 3). Concurrent cocaine-opioid use had the highest polysubstance mortality rates in 2018 among Black (5.28 per 100,000) and White (3.53 per 100,000) persons. The steepest increase in death rates during wave 3 was observed across all psychoactive drugs when combined with synthetic opioids in both racial groups. Since 2013, Black persons have died faster from cocaine-opioid and psychostimulant-opioid overdoses. Between 2013 and 2018, opioids were highly prevalent in cocaine-related deaths, increasing by 33% in White persons compared to 135% in Blacks. By 2018, opioids contributed to approximately half of psychostimulant and 85% of benzodiazepine fatal overdoses in both groups. The magnitude and type of drug combinations with the highest death rates differed by race and sex, with Black men exhibiting the highest overdose burden beginning in 2013.

CONCLUSIONS

The current drug crisis should be considered in the context of polysubstance use. Effective measures and policies are needed to curb synthetic opioid-involved deaths and address disparate mortality rates in Black communities.

Behavioral and Health Outcome Differences by Heroin or Methamphetamine Preference Among People in Rural US Communities Who Use Both Substances

Background

The United States' (US) opioid overdose epidemic has evolved into a combined stimulant/opioid epidemic, a pattern driven in part by mitigating opioid overdose risk, variable substance availability, and personal preferences. This study aimed to investigate the association between self-reported substance preference (heroin or methamphetamine) and behavioral/health outcomes among individuals who used both heroin and methamphetamine in the rural US.

Methods

The Rural Opioid Initiative is a consortium of 8 research cohorts from 10 states and 65 rural counties that recruited individuals reporting past 30-day injection of any substance or opioid substance use by any route from 1/2018 to 3/2020. Analyses were restricted to participants ⩾18 years, who self-reported either heroin or methamphetamine as their preferred substance and past 30-day use of both heroin and methamphetamine. We examined cross-sectional associations between preferred substance (heroin versus methamphetamine) and behavioral and health outcomes using random effects meta-analysis with adjusted regression models.

Results

Among 1239 participants, 61% (n = 752) reported heroin as their preferred substance. Adjusting for age, sex, and race/ethnicity, methamphetamine preference was associated with lower prevalence ratios for current naloxone possession (adjusted prevalence ratio [aPR] = 0.68; 95% Confidence Interval [95% CI] = 0.59-0.78; P-value ⩽ .001), of ever being told they had the hepatitis C virus (HCV; aPR = 0.72; 95% CI: 0.61-0.85; P-value ⩽ .001) and a personal history of overdose (aPR = 0.81; 95% CI = 0.73-0.90; P-value ⩽ .001).

Conclusion

In our study analyzing associations between preferred substance and various behavioral and health outcomes amongst people who use both heroin and methamphetamine, a majority of participants preferred heroin. Methamphetamine preference was associated with lower prevalence of naloxone possession, ever being told they had HCV, and prior history of an overdose. This study underscores the need for targeted harm reduction services for people who prefer methamphetamine in rural areas.

Exploring trends in benzodiazepine-positive fatal drug overdoses in Tennessee, 2019-2021

BACKGROUND

Benzodiazepine-positive overdoses increased between 2019 and 2021 in Tennessee. We sought to determine the changes in the number and characteristics of prescription and illicit benzodiazepine-positive fatal drug overdoses during this period.

MATERIALS AND METHODS

A statewide study was conducted to determine changes in the number and characteristics of benzodiazepine-positive drug overdose decedents using 2019-2021 data from the Tennessee State Unintentional Drug Overdose Reporting System. The analyses were limited to Tennessee residents aged ≥ 18 years. A benzodiazepine-positive overdose was defined as any benzodiazepine on toxicology, regardless of the presence of other substances. Frequencies were generated to compare demographics, circumstances, prescription history, and toxicology between 2019 and 2021 for illicit and prescription benzodiazepine-positive fatal overdoses.

RESULTS

Between 2019 and 2021, 1666 benzodiazepine-positive unintentional or undetermined fatal drug overdoses out of 5916 total overdoses that occurred among adult Tennessee residents with available toxicological information. Prescription benzodiazepines were identified in 80.7% of deaths, whereas illicit benzodiazepines were identified in 12.0% of deaths. Many decedents had an anxiety disorder (45.5%), while over half of all decedents had a history of substance use disorder (52.3%). Most benzodiazepine-positive overdoses involved fentanyl (71.3%).

CONCLUSIONS

This analysis can inform local and regional public health workers to implement focused prevention and intervention efforts for people with co-occurring mental health conditions and substance use disorders to curb overdose epidemics among persons using benzodiazepines in Tennessee. Public health campaigns should focus on educating people on appropriate prescription medication use and the dangers of obtaining substances illicitly. Given the high proportion of opioids in this population, further education also is needed on the dangers of polysubstance drug use. The differences between prescription and illicit benzodiazepine-positive fatal overdoses indicate the need to develop substance-specific prevention and treatment strategies.

The role of polysubstance use on criminal justice involvement in the United States

PURPOSE OF REVIEW

Polysubstance use, broadly defined as using more than one type of substance, disproportionately impacts those involved in the criminal justice system (CJS). This review synthesizes recent findings on polysubstance use among those involved in the CJS and highlights areas of particular concern and interventions.

RECENT FINDINGS

We use 18 recent articles to identify the prevalence and types of criminal justice involvement and correlates of polysubstance use and criminal justice involvement. We highlight latent patterns of polysubstance use among various criminal justice populations (adults, pregnant women, and youth) and differential associations with adverse substance use and criminal justice outcomes. Lastly, we discuss substance use treatment in the justice system, the role of polysubstance use in treatment access and outcomes, and substance use-related services for previously incarcerated individuals reentering society.

SUMMARY

Current research provides further evidence of the syndemic nature of polysubstance use, criminal justice involvement, and adverse outcomes, which are complicated by significant barriers to accessing evidence-based treatment in justice settings. Yet, current research is limited due to methodological inconsistency and limited focus on the social determinants of health, racial/ethnic disparities, and interventions to increase treatment and reentry services.

Types of Traumatic Experiences in Drug Overdose-Related Deaths: An Exploratory Latent Class Analysis

Aim

Drug overdose related-deaths in the US are increasing, with over 100,000 deaths occurring in 2020, an increase of 30% from the previous year and the highest number recorded in a single year. It is widely known that experiences of trauma and substance use very often co-occur, but little is known about the role of trauma in the context of drug overdose-related deaths. Latent class analysis (LCA) was used to classify drug overdose-related deaths based on type of traumatic experiences and individual, social, and substance use characteristics.

Methods

Psychological autopsy data were obtained from the University of Texas Health Science Center at Houston (UTHealth) Brain Collection. A total of 31 drug overdose-related deaths collected from January 2016 through March 2022 were included in this study. LCA was used to identify latent factors via experience of four trauma categories (illness/accidents, sexual/interpersonal violence, death/trauma to another, other situations where life was in danger). Generalized linear modeling (GLM) was used to explore differences on demographic, social, substance use, and psychiatric variables between the latent classes in separate models.

Results

LCA identified 2 classes: C1 ( n =12; 39%) was characterized by higher incidence of overall trauma exposure as well as variation in trauma type; C2 ( n =19; 61%) had lower levels of overall trauma exposure with sexual/interpersonal violence as the most frequent. GLMs indicated that C1 membership was associated with higher incidence of polysubstance use, being married, and having suicidal ideation compared to C2 membership ( p s<0.05).

Conclusion

Among individuals who died by drug overdose, the exploratory LCA identified two distinct subgroups that differed in type of trauma experienced and substance use pattern, the first group having more "typical" characteristics of drug overdoses cases, the other group less typical. This suggests that those at risk of drug overdose may not always exhibit high-risk characteristics.

Associations between Circumstances Surrounding Overdose and Underlying Classes of Polysubstance Overdose Deaths

BACKGROUND

The overdose crisis is worsening, with polysubstance overdose deaths involving psychostimulants increasing in the U.S. Substance-specific prevention and intervention activities may not be as effective for polysubstance use, so we sought to classify substances used among overdose decedents to identify unique factors related to these classes.

METHODS

We used data from the Nevada State Unintentional Drug Overdose Reporting System, Jan 2019-Jun 2021, which comes from death certificates, coroner/medical examiner reports, and postmortem toxicology. Latent class analysis, multinomial logistic regression, and Chi-squared tests determined underlying drug use classes, differences in characteristics and circumstances surrounding overdose, and assessed relationships between circumstances and drug use classes.

RESULTS

We identified four latent classes: (1) prescription drugs (19.1%), (2) predominately methamphetamine (31.4%), (3) multi-drug (28.9%), and (4) opioid and stimulant (20.6%). Compared to other classes, the prescription drug class had a higher percentage of female decedents, from rural counties, with mental health diagnoses, who died at home. The predominately methamphetamine class had a higher percentage of decedents experiencing homelessness. The multi-drug use class had higher percentage of younger and Hispanic decedents. Those in the opioid and stimulant class had higher odds of being recently released from an institutional setting, compared to the multi drug class.

CONCLUSIONS

These underlying classes were associated with several characteristics and circumstances that can prove useful for prevention, treatment, and harm reduction agencies when designing programs and interventions to target specific groups of people at-risk for drug overdose.

Polysubstance Use in Adults With Opioid Use Disorder Receiving Buprenorphine Maintenance

INTRODUCTION

Studying polysubstance use is a public health recommendation. In the United Arab Emirates, more than 80% of adults with opioid use disorder (OUD) use 2 or more nonopioid substances. This secondary analysis contrasts the characteristics of polysubstance users (OUD + ≥1 nonopioid) with OUD, explores the correlates and predictors of nonfatal overdose, and examines the impact of polysubstance use on OUD treatment outcomes using buprenorphine (BUP).

METHODS

This analysis uses data from a 16-week outpatient randomized controlled trial of 141 adults with OUD allocated to BUP + incentivized adherence and abstinence monitoring (n = 70) and BUP in usual care (control, n = 71). Outcomes were nonfatal overdose events over the preceding 12 months, positive drug screens, and treatment retention. Participant characteristics were contrasted, and bivariate statistical tests were conducted for simple associations followed by logistic regression.

RESULTS

Polysubstance use was reported by 117 participants (82.9%), the majority of whom used pregabalin 72.1% (n = 75). Compared with OUD, polysubstance users observed higher arrests (median, 1.0 [interquartile range, 0.0-3.0] vs 0.5 [interquartile range, 0.0-2.0]; P = 0.04]) and nonfatal overdose events (n = 33 [31.8%] vs 2 [10.8%], P = 0.003). Carisoprodol and injecting drug use independently predicted nonfatal overdose (adjusted odds ratio, 4.519 [95% confidence interval, 1.81-11.22] and 2.74 [95% confidence interval, 1.15-6.51], respectively). No significant difference was observed in opioid use and retention in treatment outcomes between groups.

CONCLUSION

Carisoprodol and injecting drug use increase the likelihood of nonfatal overdose in adults with OUD. Polysubstance use does not impact response to BUP treatment compared with OUD.

Risky Drinking in Adolescents and Emerging Adults: Differences between Individuals Using Alcohol Only versus Polysubstances

BACKGROUND

Factors related to risky drinking (e.g., motives, protective behavioral strategies [PBS]) may vary between youth who engage in polysubstance use compared to those who consume alcohol only. We examined differences in factors among youth who consume alcohol only compared to alcohol with other substances (i.e., polysubstance use), and correlates associated with risky drinking between the groups.

METHODS

Participants (N = 955; ages 16-24; 54.5% female) who reported recent risky drinking completed measures of alcohol/substance use, alcohol-related consequences, drinking motives, alcohol PBS, mental health symptoms, and emotion dysregulation. Participants were in the polysubstance group if they reported using at least one other substance (e.g., cannabis, stimulants) in addition to alcohol in the past three months. Chi-square and t-tests examined differences between the two groups and multiple regression analyses examined correlates of risky drinking.

RESULTS

Most participants (70.4%, n = 672) reported polysubstance use; these individuals engaged in riskier patterns of drinking, experienced more alcohol-related consequences, used fewer PBS, had stronger drinking motives (enhancement, social, coping), endorsed more mental health symptoms, and reported more emotion dysregulation. Regression models showed that emotion dysregulation significantly associated with risky drinking in the alcohol-only group; conformity and coping motives, alcohol PBS, and anxiety symptoms significantly associated with risky drinking in the polysubstance group.

CONCLUSIONS

Among risky drinking youth, results indicated youth engaging in polysubstance use have greater comorbidities and individual-level factors associated with risky drinking than youth who consume alcohol only. These findings may inform the tailoring of interventions for individuals who engage in risky drinking and polysubstance use.

Factors that influence pharmacists' efforts in addressing substance use in Nigeria: An exploratory study

Introduction

Substance use is a major global public health problem. Over the years, the burden of substance use has increased worldwide, with Nigeria having a prevalence that is substantially above the global average. Tackling this challenge requires a collaborative effort between different health professionals. Despite the critical roles pharmacists could play in substance use prevention and management, exploration of pharmacists' role in mitigating substance use in society has received limited attention in most sub-Saharan countries. In this study, we explored the experiences of pharmacists in substance use prevention and management.

Methods

We conducted semi-structured interviews to explore pharmacists' perceptions of their roles in the prevention and management of substance use in Nigeria. Following data transcription, we conducted a thematic content analysis.

Results

The four major themes that emerged included 1) the extent of pharmacists' involvement in the decision-making process for addressing substance use, 2) factors that influence pharmacists efforts in addressing substance use in Nigeria, 3) how to improve rational prescribing practices and, 4) capacity building to enhance pharmacists participation in addressing substance use.

Conclusion

Pharmacists have the opportunity to play critical roles in the prevention and management of substance use, but several individual and systemic challenges limit their full potential. Addressing these challenges is crucial in increasing pharmacists' participation in preventing and managing substance use.

The effect of concurrent access to alcohol and oxycodone on self-administration and reinstatement in rats

RATIONALE

Although polysubstance use is highly prevalent, preclinical studies that assess voluntary consumption of multiple substances at the same time are rather uncommon. Overlooking drug taking patterns commonly observed in humans may limit the translational value of preclinical models.

OBJECTIVES

Here, we aimed to develop a model of polysubstance use that could be used to assess oral operant self-administration patterns under concurrent access to alcohol and the prescription opioid oxycodone.

METHODS

After a training period where animals associated specific cues and levers with each drug, rats self-administered alcohol and oxycodone solutions concurrently in daily sessions. Oxycodone was then removed to assess potential changes in alcohol consumption. The role of cues and stress on alcohol consumption and oxycodone seeking was also examined under reinstatement conditions.

RESULTS

We found that females consumed more alcohol and oxycodone than males when given access to both drugs, and this effect on alcohol intake persisted when oxycodone was removed. Additionally, re-exposure to oxycodone cues in combination with the administration of the pharmacological stressor yohimbine drove reinstatement of oxycodone seeking in females but did not have a strong effect in males, possibly due to low levels of oxycodone intake during active self-administration in male rats. Additionally, yohimbine drove increased alcohol consumption, in line with prior findings from our group and others.

CONCLUSIONS

Taken together, this study demonstrates that rats will concurrently self-administer both oxycodone and alcohol in operant chambers, and this procedure can serve as a platform for future investigations in polysubstance use and relapse-like behavior.

A role for the circadian transcription factor NPAS2 in the progressive loss of non-rapid eye movement sleep and increased arousal during fentanyl withdrawal in male mice

RATIONALE

Synthetic opioids like fentanyl are contributing to the rise in rates of opioid use disorder and drug overdose deaths. Sleep dysfunction and circadian rhythm disruption may worsen during opioid withdrawal and persist during abstinence. Severe and persistent sleep and circadian alterations are putative factors in opioid craving and relapse. However, very little is known about the impact of fentanyl on sleep architecture and sleep-wake cycles, particularly opioid withdrawal. Further, circadian rhythms regulate sleep-wake cycles, and the circadian transcription factor, neuronal PAS domain 2 (NPAS2) is involved in the modulation of sleep architecture and drug reward. Here, we investigate the role of NPAS2 in fentanyl-induced sleep alterations.

OBJECTIVES

To determine the effect of fentanyl administration and withdrawal on sleep architecture, and the role of NPAS2 as a factor in fentanyl-induced sleep changes.

METHODS

Electroencephalography (EEG) and electromyography (EMG) was used to measure non-rapid eye movement sleep (NREMS) and rapid eye movement sleep (REMS) at baseline and following acute and chronic fentanyl administration in wild-type and NPAS2-deficient male mice.

RESULTS

Acute and chronic administration of fentanyl led to increased wake and arousal in both wild-type and NPAS2-deficient mice, an effect that was more pronounced in NPAS2-deficient mice. Chronic fentanyl administration led to decreased NREMS, which persisted during withdrawal, progressively decreasing from day 1 to 4 of withdrawal. The impact of fentanyl on NREMS and arousal was more pronounced in NPAS2-deficient mice.

CONCLUSIONS

Chronic fentanyl disrupts NREMS, leading to a progressive loss of NREMS during subsequent days of withdrawal. Loss of NPAS2 exacerbates the impact of fentanyl on sleep and wake, revealing a potential role for the circadian transcription factor in opioid-induced sleep changes.

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

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

Demographic and Geographic Variation in Fatal Drug Overdoses in the United States, 1999-2020

The U.S. drug overdose crisis has been described as a national disaster that has affected all communities. But overdose rates are higher among some subpopulations and in some places than they are in others. This article describes demographic (sex, racial/ethnic, age) and geographic variation in fatal drug overdose rates in the United States from 1999 to 2020. Across most of that timespan, rates were highest among young and middle-age (25-54 years) White and American Indian males and middle-age and older (45+ years) Black males. Rates have been consistently high in Appalachia, but the crisis has spread to several other regions in recent years, and rates are high across the urban-rural continuum. Opioids have been the main contributor, but overdoses involving cocaine and psychostimulants have also increased dramatically in recent years, demonstrating that our problem is bigger than opioids. Evidence suggests that supply-side interventions are unlikely to be effective in reducing overdoses. I argue that the U.S. should invest in policies that address the upstream structural drivers of the crisis.

Interactions between opioids and stimulants: Behavioral pharmacology of abuse-related effects

Opioid abuse continues to be a significant public health challenge, with rates of opioid-related overdose deaths increasing continuously over the last two decades. There also has been a sharp increase in overdose deaths involving stimulant drugs, primarily cocaine and methamphetamine. Recent estimates indicate a high prevalence of co-use of opioids and stimulants, which is a particularly complex problem. Behavioral pharmacology research over the last few decades has characterized interactions between opioids and stimulants as well as evaluated potential treatments. This chapter describes interactions between opioids and stimulants, with a focus on pre-clinical studies of abuse-related behavioral effects using self-administration, reinstatement, drug discrimination, place conditioning, and intracranial self-stimulation paradigms in laboratory animals. In general, the literature provides substantial evidence of mutual enhancement between opioids and stimulants for abuse-related effects, although such results are not ubiquitous. Enhanced abuse-related effects could manifest in many ways including engaging in drug seeking and taking behaviors with greater persistence, effort, and motivation and/or increased likelihood of relapse. Moreover, studies on opioid/stimulant combinations set the stage for evaluating potential treatments for polysubstance use. Behavioral pharmacology research has proven invaluable for elucidating these relationships using rigorous experimental designs and quantitative analyses of pharmacological and behavioral data.

Applying network analysis to investigate substance use symptoms associated with drug overdose

BACKGROUND

Drug overdose deaths have been increasing over the last several decades. While single substance classes, such as opioids, have been implicated in this rise, less is known about the contributions of polysubstance use (PSU) and other combinations of specific substances and symptoms that may be a risk factor for drug overdose.

METHODS

Symptoms of alcohol, cannabis, and other drug use disorders, as well as co-substance use indicators, were assessed and then examined via network analysis in a sample of young adults (N = 1540). Features of the estimated symptom network were investigated, including topology and node centrality, as well as bridge centrality, which further examines node centrality while accounting for the nodes belonging to discrete communities.

RESULTS

Individual symptoms were more strongly associated with other symptoms within the same substance class than across substance classes. Tolerance and withdrawal symptoms were the most central items in the network. However, when accounting for symptoms belonging to discrete substance classes, drug overdose emerged as a strong bridge symptom, among others.

CONCLUSIONS

As a strong bridge symptom, drug overdose had many connections with a variety of substances and symptoms, which might suggest that risk for drug overdose may be a function of overall substance use severity. Altogether, examining alcohol and substance use symptoms using a network analytic framework provided novel insights into the role PSU might play in conferring risk for drug overdose.

A Survey on Opioid Tapering Practices, Policies, and Perspectives by Pain and Palliative Care Pharmacists

Opioid tapering is an essential clinical tool to utilize for a variety of reasons, including safety and analgesic optimization. The need for individualized regimens reveals a corresponding need for healthcare providers who can actively manage patients throughout the process. Pharmacists have taken on an integral role for achieving success in opioid tapering. This survey was conducted to describe the current opioid tapering practices of pain and palliative care pharmacists. A Qualtrics survey was offered to the Society of Pain and Palliative Care Pharmacist members. The majority (87%) indicated they specialized in pain management. Almost all respondents (98%) reported providing tapering recommendations and 82% reported being involved with patient monitoring throughout the taper. The majority (multiple responses could be chosen) noted that the indication for initiating an opioid taper was due to abuse/misuse (91%), reduced overall efficacy (89%), and adverse drug reactions (78%). The most common follow-up intervals during tapering were weekly (15%), every 2 weeks (22%), and every 4 weeks (44%). This practice-based survey, though small, showed that pharmacists in pain management and palliative care are actively involved in opioid tapering. This survey will hopefully serve as a foundation for continuing research into opioid tapering and the pharmacist's role therein.

Patterns and motivations of polysubstance use: a rapid review of the qualitative evidence

INTRODUCTION

Polysubstance use-the use of substances at the same time or close in time-is a common practice among people who use drugs. The recent rise in mortality and overdose associated with polysubstance use makes understanding current motivations underlying this pattern critical. The objective of this review was to synthesize current knowledge of the reasons for combining substances in a single defined episode of drug use.

METHODS

We conducted a rapid review of the literature to identify empirical studies describing patterns and/or motivations for polysubstance use. Included studies were published between 2010 and 2021 and identified using MEDLINE, Embase, PsycINFO and Google Scholar.

RESULTS

We included 13 qualitative or mixed-method studies in our analysis. Substances were combined sequentially to alleviate withdrawal symptoms or prolong a state of euphoria ("high"). Simultaneous use was motivated by an intention to counteract or balance the effect(s) of a substance with those of another, enhance a high or reduce overall use, and to mimic the effect of another unavailable or more expensive substance. Self-medication for a pre-existing condition was also the intention behind sequential or simultaneous use.

CONCLUSION

Polysubstance use is often motivated by a desire to improve the experience based on expected effects of combinations. A better understanding of the reasons underlying substance combination are needed to mitigate the impact of the current overdose crisis.

Synthetic opioids: a review and clinical update

The term 'opioids' refers to both the natural compounds ('opiates') which are extracted from the opium poppy plant (Papaver somniferum) and their semi-synthetic and synthetic derivatives. They all possess relatively similar biochemical profiles and interact with the opioid receptors within the human body to produce a wide range of physiological effects. They have historically been used for medicinal purposes, their analgesic and sedative effects, and in the management of chronic and severe pain. They have also been used for non-medicinal and recreational purposes to produce feelings of relaxation, euphoria and well-being. Over the last decade, the emergence of an illegal market in new synthetic opioids has become a major global public health issue, associated with a substantial increase in unintentional overdoses and drug-related deaths. Synthetic opioids include fentanyl, its analogues and emerging non-fentanyl opioids. Their popularity relates to changes in criminal markets, pricing, potency, availability compared to classic opioids, ease of transport and use, rapid effect and lack of detection by conventional testing technologies. This article expands on our previous review on new psychoactive substances. We now provide a more in-depth review on synthetic opioids and explore the current challenges faced by people who use drugs, healthcare professionals, and global public health systems.

Polysubstance use trends and variability among individuals with opioid use disorder in rural versus urban settings

Rural areas of the United States have been disproportionately impacted by the opioid epidemic, exacerbated by COVID-19-related economic upheavals. While polysubstance use is an important determinant of overdose risk, variability in polysubstance use as a result of numerous factors (e.g., access, preference) has yet to be described, particularly among rural persons with opioid use disorder (PWOUD). Survey data on past-month use of prescription and illicit opioids and 12 non-opioid psychoactive drug classes were analyzed from a national sample of rural (n = 3872) and urban (n = 8153) residents entering treatment for OUD from 2012 to 2019. Trend analyses for opioid and stimulant use were compared between rural and urban PWOUD. Latent class analyses assessed substance use trends through identified typologies of rural/urban PWOUD, which then underwent comparative analyses. By 2019, prescription opioid use remained greater in rural versus urban PWOUD, and methamphetamine use showed greater growth in rural, compared to urban areas. Latent class analyses identified variability in polysubstance use, with five identical subgroups in rural/urban PWOD: high polysubstance, polyprescription, prescription opioid-focused, prescription opioid-focused with polysubstance use, and illicit opioid-focused. Polyprescription was highest in rural areas, with illicit opioid-focused use highest in urban areas. Demographic characteristics, co-morbid conditions and healthcare coverage were all associated with between-group differences. There is significant variability in polysubstance use that may identify specific prevention and treatment needs for subpopulations of OUD patients: interventions focused on reducing opioid prescriptions, early engagement with mental health resources, wider distribution of naloxone, and screening/treatment plans that take into account the use of multiple substances.

History of Respiratory Stimulants

The interest in substances that stimulate respiration has waxed and waned throughout the years, intensifying following the introduction of a new class of drugs that causes respiratory depression, and diminishing when antidotes or better drug alternatives are found. Examples include the opioids--deaths increasing during overprescribing, diminishing with wider availability of the opioid receptor antagonist naloxone, increasing again during COVID-19; the barbiturates--until largely supplanted by the benzodiazepines; propofol; and other central nervous system depressants. Unfortunately, two new troubling phenomena force a reconsideration of the status-quo: (1) overdoses due to highly potent opioids such as fentanyl, and even more-potent licit and illicit fentanyl analogs, and (2) overdose due to polysubstance use (the combination of an opioid plus one or more non-opioid drug, such as a benzodiazepine, sedating antidepressant, skeletal muscle relaxant, or various other agents). Since these now represent the majority of cases, new solutions are again needed. An interest in respiratory stimulants has been revived. This interest can be informed by a short review of the history of this interesting class of medications. We present a short history of the trajectory of advances toward more selective and safer respiratory stimulants.