Heroin and fentanyl overdoses in Kentucky: Epidemiology and surveillance

Perceived Social Isolation and Fentanyl Use Among Adults Who Inject Drugs in Rural Kentucky

Despite evidence linking perceived social isolation (PSI) with substance use disorders (SUDs), limited research has examined its effect on fentanyl use among people who inject drugs (PWID). Cross-sectional data of 350 PWID in Appalachian Kentucky were utilized to examine the association between PSI and lifetime fentanyl use. Study findings highlighted a significant association between PSI and lifetime fentanyl use. Additionally, PWID with higher scores on the PSI scale tend to use fentanyl less frequently, suggesting that social isolation may serve as a protective factor against fentanyl use within our PWID sample. This raises a concern regarding PWID forming support networks that inadvertently contribute to increased fentanyl use rather than promote recovery. Examining networks among at-risk PWID can offer valuable insights into patterns of fentanyl use and related overdoses. This can aid the design of effective policies and interventions to promote behavior change, harm reduction, and SUD treatment engagement among PWID.

National and regional trends in fentanyl seizures in the United States, 2017-2023

BACKGROUND

Rates of synthetic opioid-related deaths over time and across regions have been compared within the US, but other indicator data could help inform prevention and harm reduction as well. We compared regional trends in fentanyl seizures to examine potential shifts in illicit fentanyl availability.

METHODS

Annual trends in fentanyl seizures were examined using data from High Intensity Drug Trafficking Areas for the US overall and by region from 2017 through 2023. Multiple measures included the number of seizures, the number of powder seizures, the number of pill seizures, the total weight of seizures, the number of pills seized, and the percentage of the number of pill seizures relative to the number of total seizures.

RESULTS

The percentage of seizures in pill form in the US increased from 10.3 % in 2017 to 49.0 % in 2023 (adjusted annual percentage change [AAPC]=25.2, 95 % CI: 17.6, 33.2), with 115.6 million individual pills seized in 2023. Pill weight related to total seizure weight also increased from 0.4 % to 54.5 % (AAPC=112.6, 95 % CI: 78.6, 153.2). In 2023, the plurality of seizures was in the West, in seven out of eight of our measures, with 77.8 % of seizures in the West being in pill form. Although the Midwest had lower prevalence of seizures than the West, there were notable increases in the Midwest in the number of pill seizures (AAPC=142.2, 95 % CI: 91.9, 205.8) and number of pills seized (AAPC=421.0, 95 % CI: 272.7, 628.4). Total weight of fentanyl seized increased the most in the West (AAPC=84.6, 95 % CI: 72.3, 97.8).

CONCLUSIONS

The number and size of fentanyl seizures is increasing in the US, with the majority of seizures, especially in pill form, in the West. Continued monitoring of regional shifts in the fentanyl supply can help inform targeted prevention and public health response.

The burden of unlawful use of opioid and associated epidemiological characteristics in Africa: A scoping review

INTRODUCTION

There is an ongoing global upsurge of opioid misuse, fatal overdose and other related disorders, significantly affecting the African continent, due to resource-limited settings and poor epidemiological surveillance systems. This scoping review maps scientific evidence on epidemiological data on unlawful opioid use to identify knowledge gaps and policy shortcomings.

METHOD

The databases (PubMed, Scopus, Web of Sciences) and references were searched guided by Population, Concept, and Context (PCC) and PRISMA-ScR. The extracted characteristics examined were author/year, African country, epidemiological distribution, age group (year), gender, study design and setting, common opioid/s abused, sources of drugs, reasons for misuse, summary outcomes and future engagement.

RESULTS

A population of 55132 participated in the included studies of 68 articles, with the largest sample size of 17260 (31.31%) in a study done in South Africa, 11281(20.46%) in a study from Egypt and 4068 (7.38%) in a study from Ethiopia. The gender of the participants was indicated in 65(95.59%) papers. The mean and median age reported in 57(83.82%) papers were 15.9-38, and 22-31years. The majority of study-designs were cross-sectional, 44(64.71%), and the most used opioids were heroin, 14articles (20.59%), tramadol, 8articles (11.76%), and tramadol & heroin, 6 articles (8.82%) articles. Study-settings included urban community 15(22.06%), hospital 15(22.06%), university students 11(16.18%), and secondary school learners 6(8.82%). The highest epidemiological distributions were recorded in the South African study, 19615(35.60%), Egyptian study, 14627(26.54%), and Nigerian study 5895(10.70%). Nine (13.24%) papers reported major opioid sources as black market, friends, and drug dealers. To relieve stress, physical pain and premature ejaculation, improve mood and sleep-related problems and help to continue work, were the major reasons for taking these drugs as reported in twenty articles (29.41%).

CONCLUSION

The findings of this scoping review show significant knowledge gaps on opioid usage in the African continent. The epidemiological distribution of unlawful use of opioids among young adults, drivers, and manual labourers in both genders is evident in the findings. The reason for use necessity scrutinises the role of social interaction, friends and family influence on illicit opiate use. Therefore, there is a need for regular epidemiological surveillance and investigations into multilevel, value-based, comprehensive, and strategic long-term intervention plans to curb the opioid problem in the region.

Repeated High-dose Fentanyl Administration in Rats Reveals Minimal Tolerance to Unconsciousness, Bradycardia, Muscle Rigidity, and Respiratory Depression

BACKGROUND

Fentanyl is a synthetic opioid that is widely used in anesthesiology, but its illicit use is rapidly increasing. At high doses, fentanyl induces unconsciousness and muscle rigidity, the mechanisms of which are poorly understood. Since animal models are needed to study these effects, the aim of this study was to establish a rat model of fentanyl abuse and investigate the effects of repeated high-dose fentanyl injections on loss of righting reflex, heart rate, respiratory depression, muscle, and brain activity.

METHODS

Male and female Sprague-Dawley rats were studied (n = 40). A bolus of 100 µg/kg fentanyl was administered intravenously twice a week for 5 consecutive weeks. Time to return of righting reflex after fentanyl injection and changes in electromyography/electroencephalography activity as well as heart rate were analyzed. Additionally, arterial blood gas analysis for evaluation of ventilation was performed. Mixed-effect models with Dunnett test and effect sizes were used for statistical analysis.

RESULTS

Repeated injections resulted in a U-shaped change in time to return of righting reflex with the longest latency after the first exposure (median, 50 [first to third quartile, 36 to 56] min) and the shortest after the fifth exposure (16 [13 to 33] min). After fentanyl administration, heart rate dropped immediately by 225 beats/min (95% CI, 179 to 271; F = 3,952.16; P < 0.001), while electromyography activity increased by 291% (95% CI, 212 to 370; F = 27.51; P < 0.001) and partial pressure of arterial carbon dioxide increased by 49.4 mmHg (95% CI, 40.6 to 58.2; F = 75.97; P < 0.001) within 5 min after injection. Additionally, pH decreased by 0.48 (95% CI, 0.41 to 0.54; F = 142.00; P < 0.01), and partial pressure of arterial oxygen decreased by 50.4 mmHg (40.8 to 60.0; F = 57.90; P < 0.001). Repeated fentanyl exposures did not significantly affect the extent of these changes (EMG, F = 1.63, P = 0.237; partial pressure of arterial carbon dioxide, F = 1.23, P = 0.312; heart rate, F = 1.05, P = 0.400; pH, F = 3.05, P = 0.066; arterial partial pressure of oxygen, F = 3.35, P = 0.052). Electroencephalography analysis revealed that repeated fentanyl exposures elicited significantly higher absolute power in frequencies greater than 20 Hz as indicated by an area under the receiver operator characteristics curve greater than 0.7.

CONCLUSIONS

The authors established a rodent model of repeated high-dose fentanyl administration. Overall, significant evidence of tolerance was not observed after 10 exposures of high-dose fentanyl for any of the analyzed parameters. These results suggest that tolerance does not develop for fentanyl-induced unconsciousness, muscle rigidity, or respiratory depression.

Employment industry and opioid overdose risk: A pre- and post-COVID-19 comparison in Kentucky and Massachusetts 2018-2021

The COVID-19 pandemic has exacerbated the risk of opioid-related harm, and previous studies suggest a connection between opioid overdose risk and industry of employment. We used descriptive and spatial-statistical tests with opioid overdose data from the vital records offices of Kentucky and Massachusetts to examine opioid overdose rates by employment industry before and after COVID-19 emergency declarations. Both states had consistently high rates of opioid-related overdose mortality for individuals employed in the construction and arts, recreation, food services, and accommodation service industries. Additionally in both states, census tracts with a high percentage of renters and non-Hispanic Black residents were more likely to be located in fatal opioid-related overdose hotspots following the initial surge of COVID-19 cases. In Kentucky, census tracts with higher percentages of employment in the transportation and other services were more likely to be located in an overdose hotspot before and after the COVID-19 emergency declaration, while in Massachusetts the same was true for census tracts with high employment in manufacturing, agriculture, forest, and fisheries, and hunting.

Misclassification of opioid-involvement in drug-related overdose deaths in the United States: A scoping review

PURPOSE

Most drug-related deaths in the United States (US) in 2022 involved opioids. However, methodological challenges in overdose surveillance may contribute to underestimation of opioid involvement in the overdose crisis. This scoping review aimed to synthesize existing literature to examine the breadth and contributing sources of misclassification of opioid-related overdose deaths.

METHODS

In October 2022, we searched PubMed, Web of Science, and Scopus for studies on overdose surveillance, death certificates, and medicolegal death investigation (MDI) systems in the US published in 2013-2022. Two reviewers independently screened abstracts, reviewed full-texts, and performed data extraction of study characteristics.

RESULTS

We identified 17 studies examining misclassification in drug-related deaths. Across studies, opioid involvement in drug-related deaths was underestimated nationally by 20-35 %. Unspecified drug-related deaths differed by geographic areas and MDI systems and decreased over time. States/counties with coroner MDI systems were more likely to report unspecified overdose deaths than those with medical examiners. Integrating toxicology testing, death scene investigations, and other data with death certificates identified additional opioid-related overdose deaths, particularly those involving heroin.

CONCLUSIONS

Findings highlight the need for additional resources for surveillance efforts, training for coroners, and data integration to improve reporting of opioid involvement in overdose deaths to inform interventions.

Synaptic Structure and Transcriptomic Profiling of Reward and Sensory Brain Areas in Male Mice of Fentanyl Addiction

Background

Opioid-based medications are powerful analgesics commonly prescribed for pain management, but they are also highly addictive. The over-prescription of opioids analgesics has triggered current opioid crisis, which now has expanded to heroin and illicit synthetic opioids like fentanyl and its analogues. The side effects of fentanyl abuse have been well recognized, yet the underlying molecular adaptations across brain regions upon fentanyl exposure remain elusive.

Methods

The transmission electron microscopy (TEM) and next-generation RNA-sequencing (RNA-seq) were used to investigate the ultrastructure synaptic alterations and transcriptional profiling changes of reward and sensory brain regions in mice after fentanyl exposure.

Results

The naloxone-precipitated acute withdrawal symptoms were observed in mice exposed to fentanyl. Results of TEM showed an increase in the number of synapses, widening of synaptic gaps, and thickening of postsynaptic density in the NAc of the fentanyl addiction mice, accompanied by obvious mitochondrial swelling. RNA-seq identified differentially expressed genes (DEGs) in prefrontal cortex of mice brains after fentanyl exposure, and the expression of some addiction-related genes such as Calm4, Cdh1, Drd1/2/3/4, F2rl2, Gabra6, Ht2cr, Oprk1 and Rxfp3 showed the most striking changes among experimental groups. KEGG enrichment analysis indicated that these DEGs were related to the development of addiction behavior, dopaminergic/GABAergic/serotonergic synapse, synapse assembly/synaptic plasticity/synaptic vesicle cycle, cAMP/MAPK signaling pathway, neuroactive ligand-receptor interactions. These transcriptomic changes may be correlated with the structural and behavioral changes observed in fentanyl-exposed mice.

Discussion

The findings of this study contribute to a better understanding of the molecular mechanism of addiction behavior, which is essential for the development of optimized therapy strategies for addicts.

Respiratory Depression Associated with Opioids: A Narrative Review

OPINION

All opioids have a risk of causing respiratory depression and reduced cerebral circulation. Fentanyl has the greatest risk of causing both. This is particularly a concern when combined with illicit opioids such as diamorphine (also known as heroin). Fentanyl should not be used as a frontline potent opioid due its significant risks. Buprenorphine, a schedule III opioid, morphine, or hydromorphone is preferred, followed by oxycodone, which has a significant risk of abuse relative to buprenorphine and morphine. Although all opioids were equally effective in producing analgesia, the relative safety of each opioid is no longer a secondary concern when prescribing. In the face of an international opioid epidemic, clinicians need to choose opioid analgesics safely, wisely, and carefully.

Targeting α1- and α2-adrenergic receptors as a countermeasure for fentanyl-induced locomotor and ventilatory depression

This study assessed the ability of α1 and α2-adrenergic drugs to decrease fentanyl-induced locomotor and ventilatory depression. Rats were given saline or fentanyl, followed by: (1) naltrexone, (2) naloxone, (3) nalmefene, (4) α1 agonist phenylephrine, (5) α1 antagonist prazosin, (6) α1D antagonist BMY-7378, (7) α2 agonist clonidine, (8) α2 antagonist yohimbine or (9) vehicle. All µ-opioid antagonists dose-dependently reversed fentanyl-induced locomotor and ventilatory depression. While the α1 drugs did not alter the effects of fentanyl, clonidine dose-dependently decreased locomotion and respiration with and without fentanyl. Conversely, yohimbine given at a low dose (0.3-1 mg/kg) stimulated ventilation when given alone and higher doses (>1 mg/kg) partially reversed (∼50 %) fentanyl-induced ventilatory depression, but not locomotor depression. High doses of yohimbine in combination with a suboptimal dose of naltrexone reversed fentanyl-induced ventilatory depression, suggestive of additivity. Yohimbine may serve as an effective adjunctive countermeasure agent combined with naltrexone to rescue fentanyl-induced ventilatory depression.

Law enforcement fentanyl seizures and overdose mortality in US counties, 2013-2020

BACKGROUND

The spread of illicitly manufactured fentanyl is driving steep increases in US overdose deaths. Fentanyl seizures are correlated with state-level opioid-related mortality; however, more granular seizure surveillance information has the potential to better inform overdose prevention and harm reduction efforts.

METHODS

Using data on fentanyl pill and powder seizures from High Intensity Drug Trafficking Areas (HIDTA), we tested associations between seizure prevalence and overdose mortality, from 2013 to 2020. The primary exposure-seizure burden-was constructed by identifying counties having high (above the median) prevalence of pill, powder, or combined pill/powder seizure burden per 100,000 population. Poisson models accounted for county demographic, law enforcement and time trends.

RESULTS

During the timeframe, there were 13,842 fentanyl seizures in 606 US counties. In adjusted models, counties with a high burden of pill or powder fentanyl seizures, or both (combined pills/powder) exhibited higher total overdose mortality than non-high burden counties (pills adjusted prevalence ratio [aPR]: 1.10 [95 % confidence interval [CI]: 1.08, 1.12]; powder aPR 1.12 [CI: 1.11, 1.13]; combined pills/powder aPR: 1.27 [CI: 1.25, 1.29]). A similar pattern of associations with fentanyl seizure burden was noted for overdose deaths involving synthetic opioids (pills [aPR]: 0.99 [CI: 0.96, 1.02]; powder aPR 1.29 [CI: 1.27, 1.30]; combined pills/powder aPR 1.55 [CI: 1.52, 1.58]).

CONCLUSIONS

Law enforcement data on fentanyl seizures predicts drug overdose mortality at the county-level. Integrating these data with more traditional epidemiologic surveillance approaches has the potential to inform community overdose response efforts.

Overdose Experiences Among a Sample of Women in Jail with Opioid Use Disorder

Background:  Previous non-fatal overdose may increase risk of overdose fatality for women reentering the community following incarceration, but pre-incarceration overdose experiences are understudied. This study describes the prevalence and correlates of non-fatal overdose prior to jail among women with opioid use disorder (OUD). Methods: Women (N = 700) were randomly selected from eight Kentucky jails, screened for OUD, and interviewed as part of the NIDA-funded Kentucky Justice Community Opioid Innovation Network (JCOIN) trial. Descriptive statistics were used to examine women's prior overdose experiences, while bivariate analyses and logistic regression were used to identify correlates of overdose in the 90 days prior to jail. Results: Analyses found that 55.4% of women had overdosed in their lifetime, and 21.4% overdosed in the 90 days prior to jail. Of those who overdosed in the 90 days prior to jail, heroin (80.7%) was the most-commonly used drug prior to overdose, 35.2% received emergency, medically-attended services post-overdose, and 92.4% were administered naloxone - primarily by acquaintances. Overdosing in the 90 days prior to jail was positively correlated with identifying as a sexual minority, being from an urban community, childhood victimization, as well as recent heroin, fentanyl, and injection drug use. Conclusions: Findings indicate that prior overdose is common among jailed women with OUD, and although naloxone was often administered, few women received medically-attended services post-overdose. Results highlight the importance of distributing naloxone to community members and women reentering the community from jail, and suggest additional research is needed to understand factors inhibiting medical care following an overdose.

Wastewater Surveillance for Xylazine in Kentucky

Introduction

In the U.S., xylazine, the veterinary non-opioid sedative, has emerged as a major threat to people who use illicitly manufactured fentanyl and other drugs. The aim of this study was to compare wastewater detection of xylazine with other public health and safety surveillance data from 2019 to 2023 in Kentucky.

Methods

Wastewater samples from 5 rest areas, 2 truck weigh stations, and 4 wastewater treatment plants were tested for xylazine. Wastewater xylazine positivity rates were compared with xylazine-positive submission rates from the National Forensic Laboratory Information System and Kentucky's fatal overdoses in 6-month periods (Period 1=January-June; Period 2=July-December).

Results

Xylazine was detected in 61.6% (424 of 688) of daily wastewater samples from roadway sites/wastewater treatment plants. For roadways, detection increased from 55% (Period 1, 2021) to 94% (Period 1, 2023), and wastewater treatment plants had an overall detection of 25.8% (n=66 samples, Periods 1 and 2, 2022). Increasing roadway positivity corresponded to trends in National Forensic Laboratory Information System xylazine-positive submission rates: from 0.19 per 1,000 submissions (Period 1, 2019) to 2.9 per 1,000 (Period 2, 2022, latest available). No deaths from xylazine were reported publicly in Kentucky, although this study's authors identified 1-4 deaths (true count suppressed) in the overdose surveillance system, which, in back-of-the-envelope comparisons with other states, is far fewer than expected.

Conclusions

Wastewater signals indicate broad geographic exposure to xylazine in Kentucky, yet health outcomes data suggest otherwise. These findings may inform regional, national, and international efforts to incorporate wastewater-based drug surveillance. Harm-reduction activities along roadways and other suitable locations may be needed.

Abuse potential of fentanyl and fentanyl analogues

Introduction

In this perspective review, we evaluated the clinical management of fatal fentanyl overdose in several routes of administration, concentrating on both legally prescribed and illegally produced formulations.

Methods

A literature search was conducted on Web of Science, PubMed, and Google Scholar databases, using the following keywords: fentanyl, illicit fentanyl, deaths, misuse, abuse, and naloxone. We included only articles whose abstracts were available in English. All articles were screened using their abstracts to determine their relevance to the current review.

Results

The gold standard for treating both acute and chronic pain is fentanyl, but abuse of the drug has exploded globally since the late 2000s. Fentanyl abuse has been shown to frequently result in serious harm and even death.

Conclusion

By educating patients and physicians, making rescue kits easily accessible, developing vaccines to prevent opioid addiction, and perhaps even creating new tamper-resistant fentanyl formulations, it may be possible to prevent fentanyl misuse, therapeutic errors, and the repercussions that follow.

A scoping review of law enforcement drug seizures and overdose mortality in the United States

BACKGROUND

Leveraging law enforcement drug seizure data to better respond to the overdose crisis requires an understanding of available evidence and knowledge gaps regarding relationships between drug seizures and overdose mortality.

OBJECTIVE

This scoping review summarized peer-reviewed literature on associations between law enforcement drug seizures and drug-related mortality in the United States (US) in the era of illicitly-manufactured fentanyl, comparing study data sources, measures, methodologies, settings, and findings.

METHODS

We identified 388 non-duplicate records from three online databases searched on May 23, 2023. After title/abstract and full-text screening by two independent reviewers, 14 studies met the criteria for inclusion. The included studies tested the association between a measure related to law enforcement drug seizures and an overdose mortality outcome in the US and were published in English, in peer-reviewed journals, during or after 2013.

RESULTS

Four of 14 studies (29%) included data from the entire US, while the remaining studies focused on an individual state/city/county or a group of states/cities/counties. Synthetic opioid/fentanyl seizures represented the most frequently examined drug seizure category, and overdose deaths overall (involving any drugs) represented the most frequently examined outcome. Most studies used counts/rates of drug seizures, with fewer studies examining dosage/weight, drug combinations, the proportion of drug seizures involving a specific drug, or spatiotemporal distribution. The majority (86%) of studies reported at least one statistically significant positive association between a law enforcement drug seizure measure and an overdose mortality outcome, most consistently for fentanyl-related seizures. Results were relatively less consistent for seizures involving stimulants and other drugs.

CONCLUSIONS

Studies in this review provided consistent evidence that fentanyl-related seizure measures are positively associated with overdose mortality outcomes, despite the limitations inherent in drug seizure data, even in the absence of available information regarding seizure weight or dosage.

Examination of naloxone dosing patterns for opioid overdose by emergency medical services in Kentucky during increased fentanyl use from 2018 to 2021

BACKGROUND

Fatal overdoses involving fentanyl/fentanyl analogs (F/FA) have increased in the US, raising questions about naloxone doses for F/FA overdose reversal. Emergency medical services (EMS) data provide an opportunity to examine naloxone administration changes as fentanyl increases in the illicit opioid supply.

METHODS

Administered naloxone intranasal-equivalent total dose (INTD) in milligrams (mg) was calculated for Kentucky EMS suspected opioid overdose (SOO) encounters (n=33,846), 2018-2021, and patterns of administration were examined. County-level F/FA availability was measured as 1) proportion of fatal drug overdoses involving F/FA, and 2) F/FA police seizures. Linear mixed models estimated changes in INTD in relation to local F/FA availability accounting for patient characteristics.

RESULTS

From 2018-2021, SOOs increased by 44% (6853 to 9888) with an average INTD increase from 4.5mg to 4.7mg, with more than 99% of encounters resulting in successful reversal each year. For SOO encounters examined by outcome at the scene (i.e., non-fatal fatal vs fatal), average INTD for non-fatal were 4.6mg compared to 5.9mg for fatal overdoses. Mixed modeling found no significant relationship between INTD and the two measures for local F/FA availability.

CONCLUSION

As F/FA-involved overdose risk increased, we observed a modest increase in INTD administered in SOO EMS encounters - just slightly higher than the 4mg standard dose. The lack of significant relationship between F/FA and naloxone dose suggests that naloxone utilization in SOO with EMS involvement remains effective for overdose reversal, and that EMS naloxone dosing patterns have not changed substantially.

Association of medications for opioid use disorder with reduced risk of repeat opioid overdose in Medicaid: A cohort study

INTRODUCTION

Following a nonfatal opioid overdose, patients are at high risk for repeat overdose. The objective of this study was to examine the association of MOUD after nonfatal opioid overdose with risk of repeat overdose in the following year.

METHODS

This retrospective cohort study analyzed Missouri Medicaid claims from July 2012 to December 2021. The study identified opioid overdoses occurring between 2013 and 2020 using diagnosis codes for opioid poisoning in an inpatient or emergency department setting. The study implemented Cox models with a time-varying covariate for post-overdose receipt of MOUD.

RESULTS

During the study period, MOUD receipt after overdose more than tripled, from 4.8 % to 18.9 %. Overall, only 12.1 % of patients received MOUD in the year after index. MOUD during follow-up was associated with significantly lower risk of repeat overdose (HR = 0.34, 95 % CI = 0.14-0.82). Out of 3017 individuals meeting inclusion criteria, 13.6 % had a repeat opioid overdose within 1 year. Repeat overdose risk was higher for those whose index overdose involved heroin or synthetic opioids (HR = 1.71, 95 % CI = 1.35-2.15), but MOUD was associated with significantly reduced risk in this group (HR = 0.34, 95 % CI = 0.13-0.92).

CONCLUSIONS

MOUD receipt was associated with reduced risk of repeat overdose. Those whose index overdoses involved heroin or synthetic opioids were at greater risk of repeat overdose, but MOUD was associated with reduced risk in this group.

Multinational appraisal of the epidemiological distribution of opioid fatalities: a systematic review and meta-analysis

Background

The global or multinational scientific evidence on the distribution of opioid fatality is unknown. Hence, the current study collects epidemiological characteristics to shed light on the ongoing global or multinational opioid crisis and to promote the development of public health prevention/management strategies.

Method

All documents on PRISMA standards were retrieved via electronic databases.

Results

Among the 47 articles relevant to our studies, which depict a total population size of 10,191 individuals, the prevalence of opioid fatal overdose was 15,022 (14.74%). Among the 47 articles, 14 of them reported the gender of the participants, with 22,125 (15.79%) male individuals and 7,235 (5.17%) female individuals, and the age distribution of the participants that was most affected by the overdose was as follows: 29,272 (31.13%) belonged to the 18-34-year-old age group and 25,316 (26.92%) belonged to the less than 18-year-old age group. Eighteen studies qualified for the meta-analysis of the multinational prevalence of fatal opioid overdose, depicting an overall pooled prevalence estimate of 19.66%, with 95% CIs (0.13-0.29), I2 = 99.76% determined using the random-effects model, and Q statistic of 7198.77 (p < 0.0001). The Egger test models of publication bias revealed an insubstantial level of bias (p = 0.015). The subgroup analysis of the study design (cohort or other) revealed that others have the highest prevalence estimate of 34.37, 95% CIs (0.1600-0.5901), I2 = 97.04%, and a sample size of less than 1,000 shows the highest prevalence of 34.66, 95% CIs (0.2039-0.5234), I2 = 97.82%, compared to that of more than 1,000 with a prevalence of 12.28, 95% CIs (0.0675-0.2131), I2 = 99.85%. The meta-regression analysis revealed that sample size (less-than or greater-than 1,000), (p = 0.0098; R2 = 3.83%) is significantly associated with the observed heterogeneity.

Conclusion

Research-based findings of fatal opioid overdose are grossly lacking in middle- and low-income nations. We established that there is a need for opioid fatality surveillance systems in developing nations.

Xylazine in Overdose Deaths and Forensic Drug Reports in US States, 2019-2022

Importance

Xylazine is increasingly reported in street drugs and fatal overdoses in the US, yet state-level data are limited, hampering local public health responses.

Objective

To gather available state-level data on xylazine involvement in overdose deaths and in forensic drug reports.

Design, Setting, and Participants

This cross-sectional study was a secondary analysis of 2019 to 2022 data from the National Forensic Laboratory Information System (NFLIS), National Center for Health Statistics, and individual states' medical examiner or public health agency reports. Data were analyzed from August to October 2023.

Exposure

State.

Main Outcomes and Measures

Yearly xylazine-related overdose deaths per 100 000 residents; xylazine NFLIS drug reports, both per 100 000 residents and as a percentage of all NFLIS drug reports (from samples of drugs seized by law enforcement and analyzed by NFLIS-participating laboratories).

Results

A total of 63 state-years were included in analyses of mortality rates, while 204 state-years were included in analyses of NFLIS reports. According to the publicly available data compiled in this study, at least 43 states reported at least 1 xylazine-related overdose death from 2019 to 2022, yet yearly totals of xylazine-related deaths were available for only 21 states. Of states with data available, xylazine-involved overdose death rates were highest in Vermont (10.5 per 100 000 residents) and Connecticut (9.8 per 100 000 residents) in 2022. In 2019, 16 states had zero xylazine reports included in NFLIS reports; in 2022, only 2 states had zero xylazine reports and all but 3 states had recorded an increase in xylazine's representation in NFLIS reports. In 2022, xylazine represented 16.17% of all NFLIS reports in Delaware and between 5.95% and 7.00% of NFLIS reports in Connecticut, Maryland, District of Columbia, New Jersey, and Rhode Island, yet less than 1.0% of NFLIS reports in 35 different states.

Conclusions and Relevance

In this cross-sectional study of publicly available data on fatal overdoses and drugs analyzed by forensic laboratories, xylazine's reported presence in overdose deaths and forensic reports was concentrated in the eastern US yet extended across the country to encompass nearly all states. In spite of xylazine's geographic reach, yearly state-level numbers of xylazine-related overdose deaths were publicly available for less than half of all states.

Drug supply measures and drug overdose mortality in the era of fentanyl and stimulants

Background

Illicitly-manufactured fentanyl and stimulants have replaced prescription opioids as the primary contributors to fatal overdoses in the United States (US), yet the street supply of these substances is challenging to quantify. Building on the foundation of prior research on law enforcement drug reports, the present study compares publicly available forensic laboratory drug report measures to identify which measures account for the most variation in drug overdose mortality between states, within states over time, and in various demographic groups.

Methods

Drug reports from the National Forensic Laboratory Information System and drug overdose mortality rates from the Centers for Disease Control and Prevention were examined for all US states and the District of Columbia, 2013-2021 (459 state-years). State- and year- fixed effects models regressed drug overdose mortality rates (in the overall population and subpopulations by sex, age, and race/ethnicity) on various drug report measures, including rates per population and proportional shares of drug reports positive for fentanyl/fentanyl-related compounds, heroin, cocaine, methamphetamine, and xylazine.

Results

For drug overdose death rates in the overall population and nearly all subpopulations examined by sex, race/ethnicity, and age, the model including all drug report proportional measures represented the best-performing model (as identified via the lowest Akaike Information Criterion and highest within R-squared value), followed by the model including only the fentanyl/fentanyl-related compounds proportion.

Conclusions

Findings support the utility of publicly available drug report composition measures, particularly the proportion of fentanyl/fentanyl-related compounds, as predictors of drug overdose mortality in the US and in various subpopulations.

"Just another thing for me to stress off of": Responses to unintentional fentanyl use in a community-based study of people who use opioids

The unintentional consumption of fentanyl is a serious health risk for people who use illicit drugs. In an ongoing community-based study regarding polysubstance use among people who use opioids, we found that 17 of 58 (29%) of participants who did not endorse fentanyl use in the past thirty days tested positive for fentanyl during point-of-care urinalysis (UA). This paper describes the reactions and experiences of participants who were informed they had consumed fentanyl unintentionally, as well as how the research team handled the unanticipated occurrence of discordant results. Consistent with other recent studies, we found that people learning of unintentional fentanyl use expressed strong concerns about accidental overdose. It was common for participants to reflect on recent substance use experiences that were atypical and might have involved fentanyl, as well as to examine sources of recent drug purchases. While not all participants were surprised that they had unintentionally consumed fentanyl, all felt that learning their positive results was important due to risk of overdose. Research and medical staff have an opportunity to promote awareness of possible contamination by sharing and discussing UA test results with people who use drugs in non-judgmental manner. In addition to the widely promoted harm reduction strategy of testing drugs with fentanyl test strips, self-administered point-of-care UA, particularly after an unexpected reaction to using a drug, could provide useful information for people buying and using illicit drugs.

Residence in urban or rural counties in relation to opioid overdose mortality among Kentucky hospitalizations before and during the COVID-19 pandemic

BACKGROUND

At the beginning of the opioid overdose epidemic, overdose mortality rates were higher in urban than in rural areas. We examined the association between residence in an urban or rural county and subsequent opioid overdose mortality in Kentucky, a state highly impacted by the opioid epidemic, and whether this was modified by the COVID-19 pandemic.

METHODS

We captured hospitalizations in Kentucky from 2016 to 2020, involving an opioid using ICD-10-CM codes T40.0-T40.4 and T40.6. Patient's county was classified as urban or rural based on the NCHS Urban-Rural Classification Scheme. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of opioid overdose mortality, adjusted for demographics, hospitalization severity, and zip code SES. We assessed effect modification by the COVID-19 pandemic.

RESULTS

Overall, patients living in urban counties had 46% higher odds of opioid overdose death than patients residing in rural counties (adjusted OR=1.46; 95% CI=1.22, 1.74). Before the pandemic, patients in urban counties had 63% increased odds of opioid overdose death (adjusted OR=1.63; 95% CI=1.34, 1.97); however, during the COVID-19 pandemic, patients in urban and rural counties became more similar in regard to opioid overdose mortality (adjusted OR=0.72; 95% CI=0.45, 1.16; p-value for interaction =0.02).

CONCLUSION

Before the pandemic, living in urban counties was associated with higher opioid overdose mortality among Kentucky hospitalizations; however, during the COVID-19 pandemic, opioid overdose mortality in rural areas increased, approaching rates in urban areas. COVID-19 posed social, economic, and healthcare challenges that may be contributing to worsening mortality trends affecting both urban and rural patients.

Xylazine in Drug Seizure Reports and Overdose Deaths in the US, 2018-2022

Xylazine is increasingly reported in street drugs and fatal overdoses in the United States (US), often in combination with synthetic opioids, yet state-level xylazine data are limited, hampering local public health responses. The present study analyzed 2018-2022 state-level data from the National Forensic Laboratory Information System (xylazine-positive reports of seized drugs analyzed by forensic laboratories), the Centers for Disease Control and Prevention (population estimates, synthetic opioid overdose mortality rates), and individual states' medical examiner/public health agency reports (numbers of xylazine-involved overdose deaths). An ordinary least squares regression model predicted state-level synthetic opioid overdose mortality rates by xylazine seizure report rates, adjusting for US Census Region. In 2018, relatively low rates of xylazine seizure reports were observed, with 21 states reporting zero xylazine seizures. In 2022, only three states reported zero xylazine seizures, and the highest xylazine seizure report rates (per 100,000 residents) were observed in New Jersey (30.4), Rhode Island (22.7), Maryland (18.9), Virginia (15.5), New Hampshire (13.0), and Ohio (10.9). Data on 2019-2022 xylazine-involved overdose deaths were available for 21 states/DC (60 state-years), with the highest 2022 xylazine-involved overdose death rates (per 100,000 residents) in Vermont (10.5) and Connecticut (9.8). Finally, in 2021, at the state level, each additional reported xylazine seizure per 100,000 residents was associated with a 2% higher synthetic opioid overdose mortality rate (b=0.02, robust standard error=0.01; p=0.049). Overall, study results emphasize xylazine's increasing involvement in US law enforcement drug seizure reports and overdose deaths, primarily in the East, yet also extending across the country.

Case Report of Very-Low-Dose Fentanyl Causing Fentanyl-Induced Chest Wall Rigidity

Wooden chest syndrome (WCS) is a rare phenomenon of opioid-induced skeletal muscle rigidity causing respiratory failure and inability to ventilate. The most common opioid associated with WCS is the synthetic opioid fentanyl. Fentanyl has been called the deadliest drug in America. With the use of fentanyl in critical care units and operation rooms, it is important to better understand fentanyl's side effects and predisposing factors of WCS. The symptoms of WCS are often seen in lower fentanyl doses than what would cause apnea. In this case report, we present a case of WCS with an extremely low dose of fentanyl, i.e., 50 μcg (0.49 μcg/kg), in an 80-year-old patient with a medical history significant for chronic inflammatory demyelinating polyneuropathy (CIDP) and Guillain-Barré syndrome (GBS).

Deep Neural Networks for Fine-Grained Surveillance of Overdose Mortality

Surveillance of drug overdose deaths relies on death certificates for identification of the substances that caused death. Drugs and drug classes can be identified through the International Classification of Diseases, Tenth Revision (ICD-10), codes present on death certificates. However, ICD-10 codes do not always provide high levels of specificity in drug identification. To achieve more fine-grained identification of substances on death certificate, the free-text cause-of-death section, completed by the medical certifier, must be analyzed. Current methods for analyzing free-text death certificates rely solely on lookup tables for identifying specific substances, which must be frequently updated and maintained. To improve identification of drugs on death certificates, a deep-learning named-entity recognition model was developed, utilizing data from the Kentucky Drug Overdose Fatality Surveillance System (2014-2019), which achieved an F1-score of 99.13%. This model can identify new drug misspellings and novel substances that are not present on current surveillance lookup tables, enhancing the surveillance of drug overdose deaths.

Trends in seizures of powders and pills containing illicit fentanyl in the United States, 2018 through 2021

BACKGROUND

Prevalence of fentanyl-laced counterfeit prescription pills has been increasing in the US, possibly placing a wider population at risk for unintentional exposure. We aimed to determine whether there have been shifts in the number of fentanyl seizures and in the form of fentanyl seized in the US.

METHODS

We examined quarterly national seizure data from High Intensity Drug Trafficking Areas to determine the number of drug seizures in the US containing fentanyl from January 2018 through December 2021. Generalized additive models were used to estimate trends in the number and weight of pill and powder seizures containing fentanyl.

RESULTS

There was an increase both in the number of fentanyl-containing powder seizures (from 424 in 2018 Quarter 1 [Q1] to 1539 in 2021 Quarter 4 [Q4], β = 0.94, p < 0.001) and in the number of pill seizures (from 68 to 635, β = 0.96, p < 0.01). The proportion of pills to total seizures more than doubled from 13.8% in 2018 Q1 to 29.2% in 2021 Q4 (β = 0.92, p < 0.001). Weight of powder fentanyl seizures increased from 298.2 kg in 2018 Q1 to 2416.0 kg in 2021 Q4 (β = 1.12, p = 0.01); the number of pills seized increased from 42,202 in 2018 Q1 to 2,089,186 in 2021 Q4 (β = 0.90, p < 0.001).

CONCLUSIONS

Seizures of drugs containing fentanyl have been increasing in the US. Given that over a quarter of fentanyl seizures are now in pill form, people who obtain counterfeit pills such as those disguised as oxycodone or alprazolam are at risk for unintentional exposure to fentanyl.

Transdermal Polymeric Microneedle Sensing Platform for Fentanyl Detection in Biofluid

Opioid drugs are extremely potent synthetic analytes, and their abuse is common around the world. Hence, a rapid and point-of-need device is necessary to assess the presence of this compound in body fluid so that a timely countermeasure can be provided to the exposed individuals. Herein, we present an attractive microneedle sensing platform for the detection of the opioid drug fentanyl in real serum samples using an electrochemical detection method. The device contained an array of pyramidal microneedle structures that were integrated with platinum (Pt) and silver (Ag) wires, each with a microcavity opening. The working sensor was modified by graphene ink and subsequently with 4 (3-Butyl-1-imidazolio)-1-butanesulfonate) ionic liquid. The microneedle sensor showed direct oxidation of fentanyl in liquid samples with a detection limit of 27.8 μM by employing a highly sensitive square-wave voltammetry technique. The resulting microneedle-based sensing platform displayed an interference-free fentanyl detection in diluted serum without conceding its sensitivity, stability, and response time. The obtained results revealed that the microneedle sensor holds considerable promise for point-of-need fentanyl detection and opens additional opportunities for detecting substances of abuse in emergencies.

Discriminant Function Analyses: Classifying Drugs/Violence Victimization Typologies Among Incarcerated Rural Women

This study examined the relationship between drug use and violence victimization among incarcerated women in Appalachian Kentucky. The purpose of this study was to test the utility of Goldstein's tripartite conceptual framework among rural incarcerated women, by examining whether distinct drugs/violence nexus groups could be classified based on psychopharmacological, economic-compulsive, and systemic factors. This study used secondary data from a National Institute on Drug Abuse (NIDA)-funded grant focused on risk reduction among high-risk incarcerated women in Appalachia (N = 400). Predicted drugs/violence groups were developed using a series of discriminant function analyses. The data yielded three statistically significant discriminant models. Findings of the classified groupings indicated support for three distinct drugs/violence victimization subgroups. The psychopharmacological group showed the greatest prevalence (n = 181; Wilks's λ = .389, F = 3.94, p < .001), followed by the economic-compulsive group (n = 77; Wilks's λ = .584, F = 11.86, p < .001) and systemic group (n = 55) significant (Wilks's λ = .994, F = 2.247, p < .035). To date, this is the first study to report a relationship between systemic violence victimization among rural communities. These findings could offer novel considerations for theory development and implications for clinical practice regarding the drug-related risks for violence victimization among rural incarcerated women.

The release of abuse-deterrent OxyContin and adolescent heroin use

OBJECTIVE

To determine the association between the abuse-deterrent reformulation of OxyContin and adolescent lifetime heroin use in the United States.

METHODS

The quasi-experimental study uses individual survey data from the 1999-2019 Youth Risk Behavior Surveillance System to examine whether the reformulation of OxyContin in August 2010 affected adolescent lifetime heroin use, exploiting heterogeneity in state-level rates of OxyContin misuse before the reformulation. Multiple regression analysis adjusted for state and year fixed effects, adolescent demographics, and time-varying state characteristics and policies.

RESULTS

The release of the abuse-deterrent reformulation of OxyContin was associated with a reduction in adolescents reporting ever using heroin. An adolescent in a state with a one percentage point higher state-level rate of pre-reformulation OxyContin misuse was 1.7% points less likely to report ever using heroin after the reformulation (95% confidence interval, [(CI) = -0.007, -0.027]). These effects are strongest for adolescent males (estimate: -0.028, [(CI) = -0.016, 0.040]) and non-whites (estimate: -0.021, [(CI) = -0.005, -0.037]).

CONCLUSIONS

These results suggest the release of abuse-deterrent OxyContin is associated with a decrease in the likelihood of adolescent lifetime heroin use in states with higher pre-reformulation rates of OxyContin misuse. Pharmaceutical innovations and policies that reduce the likelihood of prescription opioid misuse may be effective in reducing adolescent lifetime heroin use.

Characterizing Opioid Overdoses Using Emergency Medical Services Data : A Case Definition Algorithm Enhanced by Machine Learning

OBJECTIVES

Tracking nonfatal overdoses in the escalating opioid overdose epidemic is important but challenging. The objective of this study was to create an innovative case definition of opioid overdose in North Carolina emergency medical services (EMS) data, with flexible methodology for application to other states' data.

METHODS

This study used de-identified North Carolina EMS encounter data from 2010-2015 for patients aged >12 years to develop a case definition of opioid overdose using an expert knowledge, rule-based algorithm reflecting whether key variables identified drug use/poisoning or overdose or whether the patient received naloxone. We text mined EMS narratives and applied a machine-learning classification tree model to the text to predict cases of opioid overdose. We trained models on the basis of whether the chief concern identified opioid overdose.

RESULTS

Using a random sample from the data, we found the positive predictive value of this case definition to be 90.0%, as compared with 82.7% using a previously published case definition. Using our case definition, the number of unresponsive opioid overdoses increased from 3412 in 2010 to 7194 in 2015. The corresponding monthly rate increased by a factor of 1.7 from January 2010 (3.0 per 1000 encounters; n = 261 encounters) to December 2015 (5.1 per 1000 encounters; n = 622 encounters). Among EMS responses for unresponsive opioid overdose, the prevalence of naloxone use was 83%.

CONCLUSIONS

This study demonstrates the potential for using machine learning in combination with a more traditional substantive knowledge algorithm-based approach to create a case definition for opioid overdose in EMS data.

Fentanyl causes naloxone-resistant vocal cord closure: A platform for testing opioid overdose treatments

BACKGROUND

High doses of the synthetic opioid fentanyl cause rapid and sustained vocal cord closure (VCC) leading to airway obstruction that prevents overdose victims from breathing. This airway effect is not caused by morphine-derived opiates (e.g. heroin), is distinct from respiratory depression, resistant to naloxone, and can be lethal. However, VCC has not been previously included in animal models of opioid overdose.

METHODS

Video laryngoscopy was used to monitor vocal cord movement in anesthetized Sprague-Dawley rats. Rats were administered saline, fentanyl (5, 25, or 50 μg/kg) or morphine (5 mg/kg) in an intravenous (IV) bolus delivered over a 10 s period. The mu opioid receptor (MOR) antagonist naloxone was administered as a pre-treatment (1 mg/kg, IV) 5 min prior to fentanyl (25 μg/kg) or a post-treatment (1 and 2 mg/kg) 1 min after fentanyl (25 μg/kg).

RESULTS

Fentanyl (25 and 50 μg/kg) caused sustained and lethal VCC within 10 s. Morphine (5 mg/kg) and fentanyl (5 μg/kg) caused only brief laryngospasm with full recovery. Pre-treatment with naloxone (1 mg/kg) prevented fentanyl-induced VCC, but naloxone (1 and 2 mg/kg) was unable to reverse VCC when administered after fentanyl.

CONCLUSIONS

These results indicate sustained VCC is a lethal physiological reaction, specific to fentanyl and resistant to naloxone treatment. While pre-treatment with naloxone prevented fentanyl-induced VCC, naloxone was unable to reverse the effect, suggesting a non-opioid receptor-mediated mechanism. These findings demonstrate the necessity of VCC inclusion in animal models of synthetic opioid overdose and the urgent need for more effective treatments for fentanyl-related overdoses.

Syringe services programs in the Bluegrass: Evidence of population health benefits using Kentucky Medicaid data

PURPOSE

To evaluate whether Kentucky counties that established a new syringe services program realized a significant decline in the incidence rate of a set of infectious disease diagnoses commonly transmitted via injection drug use.

METHODS

Longitudinal count models of within-county rates of newly diagnosed infections among populations at risk were estimated using Medicaid claims/encounters data. Generalized estimating equation models were used to report incident rate ratios of 6 diagnoses: (1) HIV; (2) hepatitis C; (3) hepatitis B; (4) osteomyelitis; (5) endocarditis; and (6) skin/soft tissue infection. To investigate whether a delay in effect was present, separate models were fit to estimate the effects of establishing a syringe services program: at its opening date, and again at 1, 3, and 6 months postopening date.

FINDINGS

Taken together, the aggregated within-county incidence rate of these 6 diagnoses was significantly lower following the implementation of a syringe services program (P < .05). Our models estimated that counties which opted to open a syringe services program realized an approximate month-over-month decline in new diagnoses of 0.5% among the population at risk.

CONCLUSIONS

These results lend further support to previous conclusions made in the public health literature regarding the efficacy of syringe services programs. Specifically, declines in incidence rates were observable beginning at 1 month post syringe services program opening. These results are particularly notable due to the typical setting in which these syringe services programs operated-rural communities of fewer than 40,000 residents.

Methodological approaches for the prediction of opioid use-related epidemics in the United States: a narrative review and cross-disciplinary call to action

The opioid crisis in the United States has been defined by waves of drug- and locality-specific Opioid use-Related Epidemics (OREs) of overdose and bloodborne infections, among a range of health harms. The ability to identify localities at risk of such OREs, and better yet, to predict which ones will experience them, holds the potential to mitigate further morbidity and mortality. This narrative review was conducted to identify and describe quantitative approaches aimed at the "risk assessment," "detection" or "prediction" of OREs in the United States. We implemented a PubMed search composed of the: (1) objective (eg, prediction), (2) epidemiologic outcome (eg, outbreak), (3) underlying cause (ie, opioid use), (4) health outcome (eg, overdose, HIV), (5) location (ie, US). In total, 46 studies were included, and the following information extracted: discipline, objective, health outcome, drug/substance type, geographic region/unit of analysis, and data sources. Studies identified relied on clinical, epidemiological, behavioral and drug markets surveillance and applied a range of methods including statistical regression, geospatial analyses, dynamic modeling, phylogenetic analyses and machine learning. Studies for the prediction of overdose mortality at national/state/county and zip code level are rapidly emerging. Geospatial methods are increasingly used to identify hotspots of opioid use and overdose. In the context of infectious disease OREs, routine genetic sequencing of patient samples to identify growing transmission clusters via phylogenetic methods could increase early detection capacity. A coordinated implementation of multiple, complementary approaches would increase our ability to successfully anticipate outbreak risk and respond preemptively. We present a multi-disciplinary framework for the prediction of OREs in the US and reflect on challenges research teams will face in implementing such strategies along with good practices.

Rural-urban differences in hospitalizations for opioid use-associated infective endocarditis in Kentucky, 2016-2019

PURPOSE

In 2016, the US rate of opioid use-associated infective endocarditis (OUA IE) hospitalizations was 3.86/100,000 for rural and 3.49/100,000 for urban residents. This study estimates the Kentucky OUA IE hospitalization rates, 2016-2019, describing differences in rural-urban residency trends, demographics, relevant comorbidities, and discharge disposition. OUA IE hospitalization rates between counties with and without syringe services programs (SSPs) are also compared.

METHODS

We used Kentucky statewide inpatient discharge records from 2016 to 2019. An OUA IE hospitalization was identified by an infective endocarditis discharge diagnosis in any diagnosis field and a concurrent diagnosis indicating opioid use. Rurality was determined based on the 2013 Rural-Urban Continuum Codes (RUCC).

FINDINGS

Kentucky's rate of OUA IE hospitalizations in 2016 was 8.9/100,000, with no significant variation between rural and urban residents. By 2019, the average rate for urban residents doubled to 17.9/100,000, significantly higher than the rural resident rate, 13.2/100,000. There were no significant rural-urban differences in percentages of those with concurrent diagnoses of HIV (<1%) or HCV (>60%). Counties that established SSPs in 2017-2018 had a 39.4% increase in OUA IE rates from 2016 to 2019, while counties without SSPs had a 79.5% increase.

CONCLUSION

The estimated 2016 Kentucky rates of OUA IE hospitalizations are 2 times higher than reported national rates, highlighting Kentucky as one of the areas most affected by this particular opioid use disorder complication. Despite challenges and barriers to the effectiveness of SSPs as a harm reduction measure, our study suggests a positive effect that should be further investigated.

Overdoses due to fentanyl and its analogues (F/FAs) push naloxone to the limit

WHAT IS KNOWN AND OBJECTIVE

Food and Drug Administration (FDA) risk evaluation and mitigation strategies (REMs) encourage emergency responders, paramedics, law enforcement agents, and even laypeople to be trained in the administration of naloxone with the intent of rescuing individuals from a known or suspected opioid overdose.

COMMENT

Although naloxone is generally safe and effective at reversing respiratory depression caused by a conventional opioid such as morphine or heroin by competing with the opioid and displacing it from the μ-opioid receptor, questions increasingly are arising as to whether naloxone can adequately reverse opioid overdoses that may involve the potent opioids fentanyl and its analogues (F/FAs). In other words, as more and more opioid overdoses involve F/FAs, can naloxone keep up?

WHAT IS NEW AND CONCLUSION

As a competitive antagonist at μ-opioid receptors, naloxone is often a life-saving agent in cases of overdose caused by conventional opioids, but it may not be versatile or powerful enough to combat the rising tide of overdoses due to fentanyl and its illicit analogues, or in cases of overdose involving combinations of opioids and non-opioids.

Interrupted time series analysis to evaluate the performance of drug overdose morbidity indicators shows discontinuities across the ICD-9-CM to ICD-10-CM transition

INTRODUCTION

On 1 October 2015, the USA transitioned from the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) to the International Classification of Diseases, 10th Revision (ICD-10-CM). Considering the major changes to drug overdose coding, we examined how using different approaches to define all-drug overdose and opioid overdose morbidity indicators in ICD-9-CM impacts longitudinal analyses that span the transition, using emergency department (ED) and hospitalisation data from six states' hospital discharge data systems.

METHODS

We calculated monthly all-drug and opioid overdose ED visit rates and hospitalisation rates (per 100 000 population) by state, starting in January 2010. We applied three ICD-9-CM indicator definitions that included identical all-drug or opioid-related codes but restricted the number of fields searched to varying degrees. Under ICD-10-CM, all fields were searched for relevant codes. Adjusting for seasonality and autocorrelation, we used interrupted time series models with level and slope change parameters in October 2015 to compare trend continuity when employing different ICD-9-CM definitions.

RESULTS

Most states observed consistent or increased capture of all-drug and opioid overdose cases in ICD-10-CM coded hospital discharge data compared with ICD-9-CM. More inclusive ICD-9-CM indicator definitions reduced the magnitude of significant level changes, but the effect of the transition was not eliminated.

DISCUSSION

The coding change appears to have introduced systematic differences in measurement of drug overdoses before and after 1 October 2015. When using hospital discharge data for drug overdose surveillance, researchers and decision makers should be aware that trends spanning the transition may not reflect actual changes in drug overdose rates.

Using prescribing and toxicology data to determine non-medical prescription drug overdose

BACKGROUND

Overdose deaths have increased dramatically in the United States and are often attributed to prescription opioids. This study presents a framework for "overdose typologies", including non-medical prescription drug use, to more accurately describe drug use patterns.

METHODS

This study examined linked prescription drug monitoring program (PDMP) and toxicology data (2016-2018) from accidental overdose deaths from a large metropolitan coroner's office in the Midwest (Indianapolis, Indiana).

RESULTS

In total, 1,112 accidental overdose deaths occurred and over two-thirds (68.0%; n = 756) were coded as an illicit drug user with no prescription opioid present in the toxicology. The most infrequent categories were prescription opioid users 5.5% (n = 61).

CONCLUSION

Linked PDMP and toxicology reports are useful in identifying drug use patterns that contribute to mortality.

Life expectancy of people who are dependent on opioids: A cohort study in New South Wales, Australia

BACKGROUND

People who are dependent on opioids have increased risk of premature death, but there are few estimates of life expectancy.

METHODS

We calculated age-specific mortality rates in a cohort of people who had at least one prescription of an opioid agonist (methadone or buprenorphine) between 2001 and 2018 in New South Wales, Australia. We used life tables to estimate life expectancy at age 18. We also estimated the potential years of life lost before age 75, decomposed by cause of death.

RESULTS

The cohort included 47,197 people, with a median of 9.8 years of follow-up. 5097 participants died, and the standardised mortality ratio (compared to the general population of New South Wales) was 6.06 (95% CI 5.90-6.23). Life expectancy at age 18 was an additional 47.5 years (95% CI 42.9-50.5) for men and 50.7 years (95% CI 45.4-54.8) for women; deficits of 14.7 and 15.8 years respectively when compared to the general population. The largest cause of death was non-communicable physical diseases, which accounted for 47% of deaths in life tables for men and 42% for women. Drug-related deaths accounted for 16% of deaths for men and 19% for women, but due to the young age at which these deaths occur, they contributed approximately one third of potential years of life lost.

CONCLUSION

In common with people with serious mental illnesses, people who are dependent on opioids have substantially reduced life expectancy. In both populations most excess deaths relate to non-communicable physical diseases.

Buprenorphine dispensing in an epicenter of the U.S. opioid epidemic: A case study of the rural risk environment in Appalachian Kentucky

BACKGROUND

Buprenorphine is a cornerstone to curbing opioid epidemics, but emerging data suggest that rural pharmacists in the US sometimes refuse to dispense this medication. We conducted a case study to explore buprenorphine dispensing practices in 12 rural Appalachian Kentucky counties, and analyze whether and how they were shaped by features of the rural risk environment.

METHODS

In this case study, we conducted one-on-one semi-structured interviews with 14 pharmacists operating 15 pharmacies in these counties to explore buprenorphine dispensing practices and perceived influences on these practices. Thematic analyses of the resulting transcripts revealed three features of the rural risk environment that shaped dispensing. To explore these three risk environment features, we analyzed policy documents (e.g., Attorney General lawsuits) and administrative databases (e.g., incarceration data). Textual documents were analyzed using thematic analyses and administrative data were analyzed using descriptive statistics; memoes explored relationships among risk environment features and dispensing practices.

RESULTS

Twelve of the 15 pharmacies limited dispensing, by refusing to serve new patients; limiting dispensing to known patients or prescribers; or refusing to dispense buprenorphine altogether. Concerns about exceeding a "Drug Enforcement Administration (DEA) cap" on opioid dispensing stifled dispensing. A legacy of aggressive and fraudulent marketing of opioid analgesics (OAs) by pharmaceutical companies and physician OA overprescribing undermined pharmacist trust in buprenorphine and in its prescribers. The escalating local war on drugs may have undermined dispensing by reinforcing stigma against people who use drugs.

CONCLUSIONS

Initiatives to increase buprenorphine prescribing must be accompanied by policy changes to increase dispensing. Specifically, buprenorphine should be removed from opioid monitoring systems; efforts to de-escalate the war on drugs should be extended to encompass rural areas; initiatives to dismantle aggressive OA marketing should be strengthened; and efforts to re-build pharmacist trust in physicians are needed.

Fentanyl but not Morphine Interacts with Nonopioid Recombinant Human Neurotransmitter Receptors and Transporters

Synthetic opioids, including fentanyl and its analogs, have therapeutic efficacy in analgesia and anesthesia. However, their illicit use in the United States has increased and contributed to the number one cause of death for adults 18-50 years old. Fentanyl and the heroin metabolite morphine induce respiratory depression that can be treated with the μ opioid receptor (MOR) antagonist naloxone. With higher or more rapid dosing, fentanyl, more than morphine, causes chest wall rigidity and can also induce rapid onset laryngospasm. Because non-MORs could mediate differing clinical manifestations, we examined the interactions of fentanyl and morphine at recombinant human neurotransmitter transporters, G protein-coupled receptors, and the N-methyl-D-aspartate glutamate receptor. Both drugs were agonists at MOR, κ, and δ opioid receptors. Morphine had little or no affinity at other human receptors and transporters (K i or IC50 value >100 µM). However, fentanyl had K i values of 1407 and 1100 nM at α 1A and α 1B adrenoceptor subtypes, respectively, and K i values of 1049 and 1670 nM at dopamine D4.4 and D1 receptor subtypes, respectively; it also blocked [3H]neurotransmitter uptake by the vesicular monoamine transporter 2 (IC50 = 911 nM). Pharmacokinetic models indicate that these Ki and IC50 values are pharmacologically relevant. Fentanyl had little affinity for other receptors or transporters. Thus, noradrenergic disposition at specific receptor subtypes in relevant organs may play a role in respiratory and cardiothoracic effects of fentanyl. Data suggest that less selective fentanyl receptor pharmacology could play a role in the different clinical effects of morphine compared with fentanyl, including fentanyl-induced deaths after illicit use. SIGNIFICANCE STATEMENT: The synthetic opioid fentanyl induces different clinical effects, including rapid onset muscular rigidity, vocal cord closure, and rapid death, than the heroin metabolite morphine. Our data indicate for the first time that the two drugs have very different effects at recombinant human neurotransmitter receptors and transporters that might explain those clinical differences.

Polysubstance Use Patterns among Justice-Involved Individuals Who Use Opioids

AIM

The current study explores pre-incarceration polysubstance use patterns among a justice-involved population who use opioids. Design: Setting: Data from prison and jail substance use programing in the state of Kentucky from 2015-2017 was examined. Participants: A cohort of 6,569 individuals who reported both pre-incarceration use of opioids and reported the use of more than one substance per day. Measurements: To determine the different typologies of polysubstance use involving opioids, latent profile analysis of the pre-incarceration thirty-day drug use of eight substances was conducted. Multinomial logistic regression predicted latent profile membership. Findings: Six unique profiles of polysubstance use involving opioids and other substances were found; Primarily Alcohol (9.4%), Primarily Heroin (19.0%), Less Polysubstance Use (34.3%), Tranquilizer Polysubstance Use (16.3%), Primarily Buprenorphine (7.8%), and Stimulant-Opioid (13.2%). Profiles differed by rural/urban geography, injection drug use, physical, and mental health symptoms. Conclusion: Findings indicate the heterogeneity of opioid use among a justice-involved population. More diverse polysubstance patterns may serve as a proxy to identifying individuals with competing physical and mental health needs. Future interventions could be tailored to polysubstance patterns during the period of justice-involvement.

Racial/ethnic differences in opioid-involved overdose deaths across metropolitan and non-metropolitan areas in the United States, 1999-2017

BACKGROUND

From 1999 to 2017, more than 400,000 Americans died from a drug overdose death involving an opioid. Early surveillance studies have observed large variations in opioid-involved overdose deaths among different geographic regions and racial/ethnic groups. The purpose of this study was to characterize trends in racial/ethnic opioid-involved overdose deaths across metropolitan and non-metropolitan areas in the United States from 1999 to 2017.

METHODS

The analysis used National Vital Statistics System data from 1999 to 2017 that were accessed through the CDC WONDER online database. Drug overdose deaths involving any opioid were identified using the International Classification of Diseases, Tenth Revision, codes and were represented as age-adjusted rates per 100,000 population. Joinpoint regression was used to examine trends in opioid-involved overdose deaths among racial/ethnic groups (non-Hispanic white, non-Hispanic black, Hispanic, non-Hispanic other) by metropolitan and non-metropolitan status (large metropolitan areas, medium-small metropolitan areas, and non-metropolitan areas).

RESULTS

The annual age-adjusted death rates for drug overdose deaths that involved any opioid significantly increased for all racial/ethnic groups in metropolitan and non-metropolitan areas from 1999 to 2017. The largest average annual increases in rates occurred among non-Hispanic whites in non-metropolitan areas (13.6% increase per year) and medium-small metropolitan areas (12.3% increase per year), followed by non-Hispanic blacks in medium-small metropolitan areas (11.3% increase per year).

CONCLUSIONS

The variations in opioid-involved overdose deaths among different racial/ethnic groups across geographic regions support the existence of multiple sub-epidemics in the current opioid overdose crisis and provide directions for targeted intervention efforts.

The Impact of Policy Changes on Heroin and Nonmedical Prescription Opioid Use among an Incarcerated Population in Kentucky, 2008-2016

In response to the opioid epidemic, there have been several national and state-level policies enacted. Consideration of how criminal justice-involved individuals are affected by such policies has received limited attention, despite disproportionately higher use among this population. Bivariate statistics examined yearly trends and logistic regressiosns examined demographic correlates of nonmedical prescription opioid and heroin use among Kentucky inmates over an eight-year time-span of important national and local policy changes (n=34,542). Results indicate that among incarcerated individuals, prior use of heroin increased 204% from 2008 to 2016, with increases possibly linked to key policy changes associated with OxyContin reformulation and state implementation of a prescription drug monitoring program. The current incarcerated population had more severe use patterns when considering general population research. Consideration of criminal justice-involved populations is crucial to understanding and treating the opioid epidemic.

Frequency of health-care utilization by adults who use illicit drugs: a systematic review and meta-analysis

AIMS

To summarize evidence on the frequency and predictors of health-care utilization among people who use illicit drugs.

DESIGN

Systematic search of MEDLINE, EMBASE and PsychINFO for observational studies reporting health-care utilization published between 1 January 2000 and 3 December 2018. We conducted narrative synthesis and meta-analysis following a registered protocol (identifier: CRD42017076525).

SETTING AND PARTICIPANTS

People who use heroin, powder cocaine, crack cocaine, methamphetamine, amphetamine, ecstasy/3,4-methyl​enedioxy​methamphetamine (MDMA), cannabis, hallucinogens or novel psychoactive substances; have a diagnosis of 'substance use disorder'; or use drug treatment services.

MEASUREMENTS

Primary outcomes were the cumulative incidence (risk) and rate of care episodes in three settings: primary care, hospital admissions (in-patient) and emergency department (ED).

FINDINGS

Ninety-two studies were included, 84% from North America and Australia. Most studies focused on people using heroin, methamphetamine or crack cocaine, or who had a diagnosis of drug dependence. We were able to conduct a meta-analysis of rates across 25 studies reporting ED episodes and 25 reporting hospital admissions, finding pooled rates of 151 [95% confidence interval (CI) = 114-201] and 41 (95% CI = 30-57) per 100 person-years, respectively; on average 4.8 and 7.1 times more often than the general population. Heterogeneity was very high and was not explained by drugs used, country of study, recruitment setting or demographic characteristics. Predictors of health-care utilization were consistent across studies and included unstable housing, drug injection and mental health problems. Opioid substitution therapy was consistently associated with reduced ED presentation and hospital admission. There was minimal research on health-care utilization by people using ecstasy/MDMA, powder cocaine, hallucinogens or novel psychoactive substances.

CONCLUSIONS

People who use illicit drugs are admitted to emergency department or hospital several times more often than the general population.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Risk factors for heroin use following release from jail or prison in adults in a Central Appalachian state between 2012-2017

Background

Corrections-involved adults with a history of opioid use disorder are at elevated risk of opioid overdose following release from correctional settings. Increased opioid prescribing restrictions and monitoring during a time when heroin is becoming cheaper and ubiquitous means that adults who misused prescription opioids prior to incarceration may be reentering communities at greater risk for heroin exposure and use.

Objectives

Determine risk factors of post-release heroin use among a sample of adults who participated in corrections-based drug treatment in Kentucky released between 2012 and 2017.

Methods

Survey data obtained as part of an ongoing evaluation of corrections-based drug treatment were examined.

Results

The final sample (N = 1,563) was majority male (80.9%). Nearly 11.0% reported past-year heroin use following their release. Depressive symptoms, polydrug use, and urban proximity were more common among participants reporting post-release heroin use. Heroin use 30 days prior to incarceration was associated with a 432.1% increase in odds of heroin use subsequent to incarceration. Post-release suicidal ideation increased odds of heroin use by 154.2%, whereas reporting satisfaction from social interactions decreased odds of use by nearly 60%. Post-release use of cocaine and diverted buprenorphine were associated with increased likelihood of heroin use during this time period, increasing odds by 469.1% and 265.9%, respectively. Residing in Central Appalachia subsequent to incarceration was associated with decreased likelihood of use.

Conclusions

In this sample, post-release heroin use was associated with concerning features, such as polydrug use, lack of social satisfaction, and suicidal ideation. These features can serve as clear targets for clinical intervention.

Characterization of diverted buprenorphine use among adults entering corrections-based drug treatment in Kentucky

BACKGROUND

Illicit, medically unsupervised use of buprenorphine (i.e., "diverted use") among vulnerable and underserved populations, such as corrections-involved adults, remains underexplored.

METHODS

Survey data (2016-2017) collected as part of a clinical assessment of incarcerated adults entering corrections-based substance use treatment in Kentucky were analyzed. For years examined, 12,915 completed the survey. Removing cases for participants who did not reside in Kentucky for >6 months during the one-year pre-incarceration period (n = 908) resulted in a final sample size of 12,007.

RESULTS

Over a quarter of the sample reported past-year diverted buprenorphine use prior to incarceration and 21.8 % reported use during the 30-days prior to incarceration, using 6.5 months and 14.3 days on average, respectively. A greater proportion of participants who reported diverted buprenorphine use had previously been engaged with some substance use treatment (77.0 %) and reported greater perceived need for treatment (79.4 %) compared to those who did not report use. Use was more likely among participants who were younger, white, male, and who reported rural or Appalachian residence. Diverted buprenorphine users also evidenced extensive polydrug use and presented with greater substance use disorder severity. Non-medical prescription opioid, heroin, and diverted methadone use were associated with increased odds of diverted buprenorphine use while kratom was not. Diverted methadone use was associated with a 252.9 % increased likelihood of diverted buprenorphine use.

CONCLUSIONS

Diverted buprenorphine use among participants in this sample was associated with concerning high-risk behaviors and may indicate barriers to accessing opioid agonist therapies for corrections-involved Kentucky residents, particularly those in rural Appalachia.

Pharmacokinetic and pharmacodynamic considerations in developing a response to the opioid epidemic

Introduction: Opioids continue to be used widely for pain management. Widespread availability of prescription opioids has led to opioid abuse and addiction. Besides steps to reduce inappropriate prescribing, exploiting opioid pharmacology to make their use safer is important.Areas covered: This article discusses the pathology and factors underlying opioid abuse. Pharmacokinetic and pharmacodynamic properties affecting abuse liability of commonly abused opioids have been highlighted. These properties inform the development of ideal abuse deterrent products. Mechanisms and cost-effectiveness of available abuse deterrent products have been reviewed in addition to the pharmacology of medications used to treat addiction.Expert opinion: The opioid crisis presents unique challenges to managing pain effectively given the limited repertoire of strong analgesics. The 5-point strategy to combat the opioid crisis calls for better preventive, treatment, and recovery services, better data, better pain management, better availability of overdose-reversing drugs and better research. There is an urgent need to decrease the cost of abuse deterrent opioids which deters their cost-effectiveness. In addition, discovery of novel analgesics, further insight into central and peripheral pain mechanisms, understanding genomic risk profiles for efficient targeted efforts, and education will be key to winning this fight against the opioid crisis.