The toxicology of heroin-related death: estimating survival times

The metabolic clock of ketamine abuse in rats by a machine learning model

Ketamine has recently become an anesthetic drug used in human and veterinary clinical medicine for illicit abuse worldwide, but the detection of illicit abuse and inference of time intervals following ketamine abuse are challenging issues in forensic toxicological investigations. Here, we developed methods to estimate time intervals since ketamine use is based on significant metabolite changes in rat serum over time after a single intraperitoneal injection of ketamine, and global metabolomics was quantified by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Thirty-five rats were treated with saline (control) or ketamine at 3 doses (30, 60, and 90 mg/kg), and the serum was collected at 21 time points (0 h to 29 d). Time-dependent rather than dose-dependent features were observed. Thirty-nine potential biomarkers were identified, including ketamine and its metabolites, lipids, serotonin and other molecules, which were used for building a random forest model to estimate time intervals up to 29 days after ketamine treatment. The accuracy of the model was 85.37% in the cross-validation set and 58.33% in the validation set. This study provides further understanding of the time-dependent changes in metabolites induced by ketamine abuse.

Fentanyl and its derivatives: Pain-killers or man-killers?

Fentanyl is a synthetic μ-opioid receptor agonist approved to treat severe to moderate pain with faster onset of action and about 100 times more potent than morphine. Over last two decades, abuse of fentanyl and its derivatives has an increased trend, globally. Currently, the United States (US) faces the most serious situation related to fentanyl overdose, commonly referred to as the opioid epidemic. Nowadays, fentanyl is considered as the number one cause of death for adults aged 18-45 in the US. Synthesis and derivatization of fentanyl is inexpensive to manufacture and easily achievable. Indeed, more than 1400 fentanyl derivatives have been described in the scientific literature and patents. In addition, accessibility and efficacy of fentanyl and its derivatives can play a potential role in misuse of these compounds as a chemical weapon. In this review, the properties, general pharmacology, and overdose death cases associated with fentanyl and selected derivatives are presented. Moreover, current opioid epidemic in the US, Moscow theatre hostage crisis, and potential misuse of fentanyl and its derivatives as a chemical weapon are disclosed.

The relationship between felt stigma and non-fatal overdose among rural people who use drugs

BACKGROUND

Drug overdose deaths in the United States exceeded 100,000 in 2021 and 2022. Substance use stigma is a major barrier to treatment and harm reduction utilization and is a priority target in ending the overdose epidemic. However, little is known about the relationship between stigma and overdose, especially in rural areas. We aimed to characterize the association between felt stigma and non-fatal overdose in a multi-state sample of rural-dwelling people who use drugs.

METHODS

Between January 2018 and March 2020, 2,608 people reporting past 30-day opioid use were recruited via modified chain-referral sampling in rural areas across 10 states. Participants completed a computer-assisted survey of substance use and substance-related attitudes, behaviors, and experiences. We used multivariable logistic regression with generalized estimating equations to test the association between felt stigma and recent non-fatal overdose.

RESULTS

6.6% of participants (n = 173) reported an overdose in the past 30 days. Recent non-fatal overdose was significantly associated with felt stigma after adjusting for demographic and substance use-related covariates (aOR: 1.47, 95% CI: 1.20-1.81). The association remained significant in sensitivity analyses on component fear of enacted stigma items (aOR: 1.48, 95% CI: 1.20-1.83) and an internalized stigma item (aOR: 1.51, 95% CI: 1.07-2.14).

CONCLUSIONS

Felt stigma related to substance use is associated with higher risk of non-fatal overdose in rural-dwelling people who use drugs. Stigma reduction interventions and tailored services for those experiencing high stigma are underutilized approaches that may mitigate overdose risk.

Clinical Pharmacokinetics and Pharmacodynamics of Naloxone

Naloxone is a World Health Organization (WHO)-listed essential medicine and is the first choice for treating the respiratory depression of opioids, also by lay-people witnessing an opioid overdose. Naloxone acts by competitive displacement of opioid agonists at the μ-opioid receptor (MOR). Its effect depends on pharmacological characteristics of the opioid agonist, such as dissociation rate from the MOR receptor and constitution of the victim. Aim of treatment is a balancing act between restoration of respiration (not consciousness) and avoidance of withdrawal, achieved by titration to response after initial doses of 0.4-2 mg. Naloxone is rapidly eliminated [half-life (t1/2) 60-120 min] due to high clearance. Metabolites are inactive. Major routes for administration are intravenous, intramuscular, and intranasal, the latter primarily for take-home naloxone. Nasal bioavailability is about 50%. Nasal uptake [mean time to maximum concentration (Tmax) 15-30 min] is likely slower than intramuscular, as reversal of respiration lag behind intramuscular naloxone in overdose victims. The intraindividual, interindividual and between-study variability in pharmacokinetics in volunteers are large. Variability in the target population is unknown. The duration of action of 1 mg intravenous (IV) is 2 h, possibly longer by intramuscular and intranasal administration. Initial parenteral doses of 0.4-0.8 mg are usually sufficient to restore breathing after heroin overdose. Fentanyl overdoses likely require higher doses of naloxone. Controlled clinical trials are feasible in opioid overdose but are absent in cohorts with synthetic opioids. Modeling studies provide valuable insight in pharmacotherapy but cannot replace clinical trials. Laypeople should always have access to at least two dose kits for their interim intervention.

Differences in heroin overdose deaths in Australia by age, 2020-2022: Disease and estimated survival times

Background

The age of people who use illicit opioids has increased, with a clinical picture of accelerated ageing. The study aimed to determine, stratified by age: 1. The circumstances and characteristics of heroin-related toxicity deaths in Australia, 2020-2022; 2. The toxicological profile and autopsy findings; 3. The proportion of cases in which blood 6-acetyl morphine (6AM) was detected, as a measure of survival time.

Methods

Retrospective study of 610 cases of fatal heroin-related drug toxicity in Australia, 2020-2022. Cases were stratified as: <30 years, 30-39 years, 40-49 years, ≥50 years.

Results

Compared to the youngest group, those aged ≥50 years were more likely to have a history of chronic pain (12.4 v 3.3 %), to have their death attributed to combined drug toxicity/disease (20.1 v 3.3 %), and to have evidence of a sudden collapse (21.3 v 11.1 %). There were no differences in free morphine concentrations or glucuronide concentrations. Compared to the youngest group, however, the two older groups were significantly more likely to have 6AM present in blood, a proxy measure of a shorter survival time (52.0, 55.2 v 34.5 %). Compared to the youngest group, cases aged ≥50 years were more likely to be diagnosed with cardiomegaly (44.0 v 16.7 %), coronary artery disease (46.0 v 15.0 %), emphysema (35.0 v 5.1 %), hepatic steatosis (15.4 v 3.4 %), hepatic fibrosis (17.6 v 3.4 %), and cirrhosis (19.8 v 0.0 %).

Conclusions

Older cases of heroin overdose had more extensive heart, lung, and liver disease, and appeared more likely to have shorter survival times.

A descriptive coronial study of heroin toxicity deaths in Australia, 2020-2022: Characteristics, toxicology and survival times

BACKGROUND AND AIMS

Mortality rates among people who use heroin are estimated to be 15 times that of the general population. The study aimed to determine (1) the case characteristics and circumstances of death of heroin-related toxicity deaths in Australia, 2020-2022; (2) their toxicological profile and major autopsy findings; (3) the proportion of cases in which blood 6-acetyl morphine (6AM) was detected, as a proxy measure of survival times; and (4) compare 6AM positive and negative cases on toxicology, circumstances of death and acute clinical presentation.

DESIGN

Retrospective study of heroin toxicity deaths in Australia, 2020-2022, retrieved from the National Coronial Information System.

SETTING

This study was conducted Australia-wide.

CASES

There were 610 cases of fatal heroin-related drug toxicity.

MEASUREMENTS

Information was collected on characteristics, manner of death, toxicology and autopsy results.

FINDINGS

The mean age was 42.6 years (range 18-73 years), 80.5% were male and 7.5% were enrolled in a drug treatment programme. The circumstances of death were as follows: unintentional drug toxicity (86.2%), combined unintentional drug toxicity/disease (11.3%) and intentional drug toxicity (2.5%). The median free morphine concentration was 0.17 mg/L (range 0.00-4.20 mg/L). Psychoactive drugs other than heroin were present in 95.2% (Confidence Interval 93.1%-96.8%), most commonly hypnosedatives (62.3%, 58.2%-66.4%) and psychostimulants (44.8%, 40.7%-49.1%). Major autopsy findings of clinical significance included acute bronchopneumonia (14.8%, 11.3%-18.8%), emphysema (16.9%, 13.2%-21.1%), cardiomegaly (30.1%, 12.7%-28.2%), coronary artery disease (27.4%, 23.0%-32.3%), coronary replacement fibrosis (13.4%, 10.1%-17.3%), hepatic cirrhosis (8.8%, 6.6%-12.2%) and renal fibrosis (10.3%, 7.3%-14.0%). In 47.0% (42.3%-51.2%), 6AM was present in blood.

CONCLUSIONS

The 'typical' heroin overdose case in Australia from 2020 to 2022 was a male who injected heroin, aged in the 40s, not enrolled in a treatment programme and had used multiple drugs. In over half of cases, there had been a sufficient survival time for 6-acetyl morphine to have been metabolised, which may indicate times in excess of 20-30 min.

Comparison of the effects of fentanyls and other μ opioid receptor agonists on the electrical activity of respiratory muscles in the rat

Introduction: Deaths due to overdose of fentanyls result primarily from depression of respiration. These potent opioids can also produce muscle rigidity in the diaphragm and the chest muscles, a phenomenon known as Wooden Chest Syndrome, which further limits ventilation. Methods: We have compared the depression of ventilation by fentanyl and morphine by directly measuring their ability to induce muscle rigidity using EMG recording from diaphragm and external and internal intercostal muscles, in the rat working heart-brainstem preparation. Results: At equipotent bradypnea-inducing concentrations fentanyl produced a greater increase in expiratory EMG amplitude than morphine in all three muscles examined. In order to understand whether this effect of fentanyl was a unique property of the phenylpiperidine chemical structure, or due to fentanyl's high agonist intrinsic efficacy or its lipophilicity, we compared a variety of agonists with different properties at concentrations that were equipotent at producing bradypnea. We compared carfentanil and alfentanil (phenylpiperidines with relatively high efficacy and high to medium lipophilicity, respectively), norbuprenorphine (orvinolmorphinan with high efficacy and lipophilicity) and levorphanol (morphinan with relatively low efficacy and high lipophilicity). Discussion: We observed that, agonists with higher intrinsic efficacy were more likely to increase expiratory EMG amplitude (i.e., produce chest rigidity) than agonists with lower efficacy. Whereas lipophilicity and chemical structure did not appear to correlate with the ability to induce chest rigidity.

Preliminary effectiveness of online opioid overdose and naloxone administration training and impact of naloxone possession on opioid use

BACKGROUND

Despite the demonstrated value of opioid overdose education and naloxone distribution (OEND) programs, uptake and utilization remains low. Accessibility to OEND is limited and traditional programs may not reach many high-risk individuals. This study evaluated the effectiveness of online opioid overdose and naloxone administration education and the impact of naloxone possession.

METHODS

Individuals with self-reported illicit use of opioids were recruited via Craigslist advertisements and completed all assessments and education online via REDCap. Participants watched a 20-minute video outlining signs of opioid overdose and how to administer naloxone. They were then randomized to either receive a naloxone kit or be given instructions on where to obtain a kit. Effectiveness of training was measured with pre- and post-training knowledge questionnaires. Naloxone kit possession, overdoses, opioid use frequency, and treatment interest were self-reported on monthly follow-up assessments.

RESULTS

Mean knowledge scores significantly increased from 6.82/9.00 to 8.22 after training (t(194)=6.85, p <0.001, 95% CI[1.00, 1.81], Cohen's d=0.85). Difference in naloxone possession between randomized groups was significant with a large effect size (p <0.001, diff=0.60, 95% CI[0.47, 0.73]). A bidirectional relationship was found between naloxone possession and frequency of opioid use. Overdoses and treatment interest were similar across possession status.

CONCLUSIONS

Overdose education is effective in online video format. Disparity in naloxone possession across groups indicates barriers to obtaining naloxone from pharmacies. Naloxone possession did not influence risky opioid use or treatment interest and its impact on frequency of use warrants further investigation.

TRIAL REGISTRATION

Clinitaltrials.gov-NCT04303000.

Feasibility and acceptability of online opioid overdose education and naloxone distribution: Study protocol and preliminary results from a randomized pilot clinical trial

Drug overdose is the leading cause of accidental death in the United States, with over 70% of drug related fatalities resulting from the use of opioids. Federal agencies have responded to this crisis with various recommendations including enhancing harm reduction approaches such as training laypersons to administer naloxone through Opioid Overdose Education and Naloxone Distribution (OEND) programs. Several studies have demonstrated that OEND programs effectively reduce opioid overdose mortality and are both safe and cost-effective, however, they are typically implemented in urban areas as part of large medical center research programs, needle exchanges, or drug treatment programs. Individuals living in areas without these programs or services lack access to critical and life-saving OEND. The current study examined the acceptability and feasibility of online recruitment, online opioid overdose education, and remote distribution of naloxone kits. Persons who illicitly use opioids and are at risk for overdose were recruited through online media and completed an opioid use questionnaire. If interested in receiving opioid overdose and naloxone administration training, participants completed pre- and post-intervention knowledge questionnaires, engaged in audiovisual training, and were randomized to either receive a naloxone kit or be given information on where they could obtain one. Preliminary results indicate feasibility and acceptability as evidenced by strong recruitment and retention, as well as high participant satisfaction ratings. Successful implementation of remote OEND through this project supports future employment of similar remote programs to expand this critical harm reduction strategy to high-risk individuals in areas lacking traditional OEND programs.

Trial Registration #

Clinitaltrials.gov- NCT04303000.

Sweden's first Take-Home Naloxone program: participant characteristics, dose endpoints and predictors for overdose reversals

BACKGROUND

Opioid overdoses are a growing concern, particularly among people who inject drugs. Sweden, with a comparatively high proportion of drug-related mortality, introduced its first Take-Home Naloxone (THN) program in 2018, at the Stockholm needle and syringe program (NSP). In this study we compare THN participant characteristics regarding refills and overdose reversals as well as investigate predictors associated with number of reversals. We also investigate interventions performed in overdose situations and endpoints for naloxone doses.

METHODS

This was a prospective open inclusion cohort study conducted between January 24^th 2018 and March 31^st 2022 at the Stockholm NSP. Participants received THN, free of charge, after a training session and provided data regarding drug use and overdose experiences. During refill visits, participants reported if the naloxone was used for overdose reversal and, if so, responded to a ten-item questionnaire which included stating whether the naloxone recipient was the participant themselves or somebody else. Questionnaire data was combined with NSP database demographic data. Zero-inflated Poisson regression was applied to analyse predictors for number of reported overdose reversals.

RESULTS

Among study participants (n = 1,295), 66.5% stated opioids as their primary drug, and 61.4% and 81.0% had previous experience of a personal or witnessed overdose, respectively. Overall, 44.0% of participants reported a total of 1,625 overdose reversals and the victim was known to have survived in 95.6% of cases. Stimulant use (aIRR 1.26; 95% CI 1.01, 1.58), benzodiazepine use (aIRR 1.75; 95% CI 1.1, 2.78) and homelessness (aIRR 1.35; 95% CI 1.06, 1.73) were predictors associated with an increased number of reported overdose reversals. Mortality was higher among those who reported at least one overdose reversal (HR 3.4; 95% CI 2.2, 5.2).

CONCLUSIONS

An NSP's existent framework can be utilised to effectively implement a THN program, provide basic training and reach numerous high-risk individuals. During the four-year study, THN participants reversed a sizeable number of potentially fatal overdoses, of which many were reported by participants whose primary drug was not opioids. Naloxone refill rate was high, indicating that participants were motivated to maintain a supply of naloxone in case of future overdose events.

Heroin-Related Fatalities in Jeddah, Saudi Arabia, between 2008 and 2018

To date, epidemiological studies have not evaluated heroin-related deaths in the Middle East and North African regions, especially Saudi Arabia. All heroin-related postmortem cases reported at the Jeddah Poison Control Center (JPCC) over a 10-year period (21 January 2008 to 31 July 2018) were reviewed. In addition, liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was utilized to determine the 6-monoacetylmorphine (6-MAM), 6-acetylcodeine (6-AC), morphine (MOR), and codeine contents in unhydrolyzed postmortem specimens. Ninety-seven heroin-related deaths were assessed in this study, and they represented 2% of the total postmortem cases at the JPCC (median age, 38; 98% male). In the blood, urine, vitreous humor, and bile samples, the median morphine concentrations were 280 ng/mL, 1400 ng/mL, 90 ng/mL, and 2200 ng/mL, respectively; 6-MAM was detected in 60%, 100%, 99%, and 59% of the samples, respectively; and 6-AC was detected in 24%, 68%, 50%, and 30% of the samples, respectively. The highest number of deaths (33% of total cases) was observed in the 21-30 age group. In addition, 61% of cases were classified as "rapid deaths," while 24% were classified as "delayed deaths." The majority (76%) of deaths were accidental; 7% were from suicide; 5% were from homicide; and 11% were undetermined. This is the first epidemiological study to investigate heroin-related fatalities in Saudi Arabia and the Middle East and North African region. The rate of heroin-related deaths in Jeddah remained stable but increased slightly at the end of the study period. Most patients were heroin-dependent abusers and from the middle-aged group. The availability of urine, vitreous humor, and bile specimens provided valuable information regarding the opioids that were administered and the survival time following heroin injection.

Overdose and suicide are different phenomena among opioid users that require different clinical management

Given the high rates of mental health comorbidity among opioid users, and increasing rates of opioid prescription for chronic pain, psychiatrists and mental health clinicians are likely to treat patients who are dependent on opioids. Among such patients, many will have histories of opioid overdose or suicide attempts. It is tempting to assume that these are related behaviours and that 'accidental' overdoses are actually suicide attempts. We provide evidence here to demonstrate that while some overdoses are intentional, most are not. More than half of deaths among opioid users are due to unintentional overdose. Suicides constitute a minority: less than 10% of heroin user deaths are estimated to be due to suicide, as are 20-30% of prescribed opioid fatalities. Moreover, suicide attempts are more commonly made using means other than opioids. Overdose and suicide among opioid dependent patients are two distinct phenomena, associated with different risk factors, that need to be separately assessed and their respective risk managed.

Characteristics and circumstances of cocaine-related completed suicide in Australia, 2000-2021

BACKGROUND

There has been a substantial global increase in cocaine use and associated harms. The current study aimed to: 1. Determine the case characteristics and circumstances of death of cocaine-related suicide in Australia 2000-2021; and 2. Determine the toxicological profiles of cases.

METHODS

Retrospective study of cocaine-related death in Australia, 2000-2021, retrieved from the National Coronial Information System (NCIS). Suicide intent was based upon the NCIS code for "Intentional Self-harm", derived from case circumstances and coroners' conclusions. Sex comparisons were made for all major variables.

RESULTS

A total of 157 cases were identified, 82.2% male, 79.5% employed, with a mean age of 32.3 years. Concerns for mental health were documented in 65.6%, a previous suicide attempt in 21.0%, a history of substance use treatment and/or negative consequences of substance use in 45.9% and injecting drug use in 14.6%. Manner of death amongst both sexes was predominantly by physical means (82.8%). Written intent was documented in 29.3%. Intense agitation prior to the incident was noted in 28.0% and conflict in 24.8%. The median blood cocaine concentration was 0.060 mg/L (range 0.007-5.500). Other drugs were present in 95.5%, most commonly alcohol (63.1%) with a median concentration of 0.140 g/100 ml. Psychostimulants other than cocaine were present in 31.2%.

CONCLUSIONS

The 'typical' cocaine-related suicide case was a male, aged in their early thirties, who was highly likely to be employed. The majority of cases used physical means, and a substantial minority were highly agitated and engaged in conflict prior to the fatal incident.

Rates, characteristics and toxicology of cocaine-related deaths in Australia, 2000-2021

AIMS

To (i) assess the population mortality rates of cocaine-related deaths in Australia, 2000 to 2021; (ii) determine the circumstances of death and case characteristics; and (iii) determine their toxicological profile.

DESIGN

Retrospective study of cocaine-related deaths in Australia, 2000 to 2021, retrieved from the National Coronial Information System.

SETTING

Australia-wide.

CASES

A total of 884 cases, mean age = 33.8 (SD, 10.0) years and 86.5% (n = 765) male.

MEASUREMENTS

Information was collected on characteristics, manner of death and toxicology. Only cases in which the presence of blood cocaine and/or metabolites were included.

FINDINGS

Population rates did not significantly increase during 2001-2011 (annual percentage change [APC] = 1.5; CI, -3.2, 6.5), but from 2012, there was a marked acceleration (APC = 20.0, 95% CI, 15.5, 25.3). Circumstances of death were unintentional drug toxicity (70.7%, n = 625), intentional self-harm (17.8%, n = 157), traumatic accident (11.5%, n = 102). The proportion of cases constituted by unintentional toxicity declined across the study period (APC = -2.6; CI, -3.1, -2.1). There was a substantial decline in the proportion of cases with a history of injecting drug use (APC = -5.7; CI, -6.5, -4.9) and with a history of substance use problems (APC = -3.2; CI, -3.9, -2.5). Both cocaine (0.100 vs 0.050 mg/L, P < 0.001) and benzoylecgonine (0.590 vs 0.240 mg/L, P < 0.001) concentrations were higher amongst toxicity cases than in cases of death from traumatic injury. Cocaethylene was present in 26.4% (n = 233), levamisole in 18.6% (n = 164) and lignocaine in 11.5% (n = 102). Psychoactive drugs in addition to cocaine were present in 92.9% (n = 821), most commonly opioids (50.5%, n = 446), alcohol (47.1%, n = 416), hypnosedatives (43.2%, n = 382) and psychostimulants (30.3%, n = 268). There was a steady decline in the proportion of opioid positive cases (APC = -5.4; CI, -6.3, -4.5).

CONCLUSIONS

There was a large increase in cocaine-related deaths across Australia from 2000 to 2021. This was accompanied by changes in case profiles, with histories of injecting drug use and substance use problems, as well as recent opioid use, becoming less prominent.

Prevalence and correlates of using opioids alone among individuals in a residential treatment program in Michigan: implications for overdose mortality prevention

BACKGROUND

Avoiding use of opioids while alone reduces overdose fatality risk; however, drug use-related stigma may be a barrier to consistently using opioids in the presence of others.

METHODS

We described the frequency of using opioids while alone among 241 people reporting daily heroin use or non-prescribed use of opioid analgesic medications (OAMs) in the month before attending a substance use disorder treatment program in the Midwestern USA. We investigated drug use-related stigma as a correlate of using opioids while alone frequently (very often vs. less frequently or never) and examined overdose risk behaviors associated with using opioids while alone frequently, adjusted for sociodemographic and clinical characteristics.

RESULTS

The sample was a median age of 30 years, 34% female, 79% white, and nearly all (91%) had experienced an overdose. Approximately 63% had used OAMs and 70% used heroin while alone very often in the month before treatment. High levels of anticipated stigma were associated with using either opioid while alone very often (adjusted PR: 1.20, 95% CI: 1.04-1.38). Drinking alcohol and taking sedatives within two hours of OAMs very often (vs. less often or never) and using OAMs in a new setting very often (vs. less often or never) were associated with using OAMs while alone very often. Taking sedatives within two hours of using heroin and using heroin in a new setting very often (vs. less often or never) were associated with using heroin while alone very often.

CONCLUSION

Anticipated stigma, polysubstance use, and use in a new setting were associated with using opioids while alone. These findings highlight a need for enhanced overdose harm reduction options, such as overdose detection services that can initiate an overdose response if needed. Addressing stigmatizing behaviors in communities may reduce anticipated stigma and support engagement and trust in these services.

A Forensic Diagnostic Algorithm for Drug-Related Deaths: A Case Series

The best evidence provided in the literature worldwide suggests the importance of harmonizing the investigation in drug-related fatalities. In this study, the application of a multidisciplinary approach in eight cases of drug-related deaths is presented. Although death scene findings could be highly suggestive of drug intoxication, external examination and toxicological screening test alone are insufficient. There are several variables, and it is not always easy to give the proper interpretation of the drug detection. A complete autopsy is necessary to correctly complete organ and tissues sampling for further histological and toxicological studies and obtain body fluids. The use of peripheral blood is recommended to avoid artifacts. The collection of many specimens is warranted to get more responses. The sampling aims to provide a picture of the distribution of the substance in the body. The sample and the selection of the drugs and the matrices to investigate are case-dependent. The presented diagnostic algorithm provides the coroner with all the elements to investigate drug-related deaths and cooperate with toxicologists. Toxicological forensic diagnosis is still extremely heterogeneous in regional and national contexts. Funding for method development, research, networking, facilities, and technologies improvement is mandatory to standardize the toxicological investigation.

Characteristics of fatal 'novel' synthetic opioid toxicity in Australia

BACKGROUND

Aims: To determine 1. The characteristics of all recorded cases of fatal drug poisoning involving novel synthetic opioids (NSOs) in Australia; 2. The toxicology of cases; and 3. The major autopsy findings.

METHODS

Review of all fatal poisonings related to NSOs in Australia 2000-2021 identified in the National Coronial Information System.

RESULTS

Thirty-one cases were identified, 96.8% due to unintentional drug toxicity. The mean age was 31.9 years and 87.1% were male. Only six were aged over forty. A history of substance use problems was documented in 80.6% and 58.1% had a history of injecting drug use. In 32.3% the final route of administration of a NSO was by non-injecting routes of administration. Ten NSOs were identified. Fentanyl analogues were present in 67.2%, most commonly furanylfenatyl (19.4%). Other NSO types were present in 39.7%, most commonly U-47700 (35.5%). Substances other than NSOs were present in 90.3%, most commonly benzodiazepines (67.7%) and other opioids (51.6%). A CNS depressant in addition to NSOs was present in 90.3%, and a new psychoactive substance other than a NSO in 25.8%. Pulmonary oedema was diagnosed in 82.6%, aspiration of vomitus in 30.4%, and acute bronchopneumonia in 17.4%.

CONCLUSIONS

Ten NSOs were identified. Case characteristics suggest a younger cohort whose profile is more typical of use of other NPS than of the established opioids. A large proportion used NSOs by non-injecting routes of administration.

Pharmacokinetic considerations for community-based dosing of nasal naloxone in opioid overdose in adults

INTRODUCTION

The administration of the opioid antagonist naloxone in the community is a measure to prevent death from opioid overdose. Approved nasal naloxone sprays deliver initial doses of 0.9 to 8 mg. The level of the initial community dose is controversial, as the scientific base is weak.In this review knowledge of the pharmacokinetics of nasal, both approved and improvised nasal sprays, and intramuscular naloxone will be utilized to evaluate dose-effect relationships in previous studies of opioid overdose outcomes.

AREAS COVERED

The aim was to present scientifically based considerations on the initial nasal naloxone doses currently available, which reasonably balances the effect and adverse outcomes, given that at least two doses are at hand. Also included in these considerations is the challenge by illicitly manufactured fentanyl and analogs.This paper is based on both peer-reviewed and grey literature identified by several searches, of such as naloxone pharmacokinetics/formulations/outcomes/emergency medical services, in PubMed and Embase.

EXPERT OPINION

There is little scientific evidence that supports the use of initial systemic dosing that exceeds 0.8 mg in the community. Higher doses increase the risk of withdrawal symptoms feared in people who use opioids. Many obstacles may reduce the potential of community-administered naloxone.

Socioeconomic correlates of incident and fatal opioid overdose among Swedish people with opioid use disorder

Background

Opioid overdose (OD) and opioid OD death are major health threats to people with opioid use disorder (OUD). Socioeconomic factors are underexplored potential determinants of opioid OD. In this study, we assessed socioeconomic and other factors and their associations with incident and fatal opioid OD, in a cohort consisting of 22,079 individuals with OUD.

Methods

We performed a retrospective, longitudinal study based on Swedish national register data for the period January 2005–December 2017. We used Cox proportional hazard models to investigate the risk of incident and fatal opioid OD as a function of several individual, parental and neighborhood covariates.

Results

Univariate analysis showed that several covariates were associated with incident and fatal opioid OD. In the multivariate analysis, incident opioid OD was associated with educational attainment (Hazard ratio [HR] 0.96; 95% confidence interval [CI] 0.94–0.97), having received social welfare (HR 1.31; 95% CI 1.22–1.39), and criminal conviction (HR 1.53; 95% CI 1.42–1.65). Fatal opioid OD was also associated with criminal conviction (HR 1.93; 95% CI 1.61–2.32).

Conclusion

Individuals with low education and receipt of social welfare had higher risks of incident opioid OD and individuals with criminal conviction were identified as a risk group for both incident and fatal opioid OD. Our findings should raise attention among health prevention policy makers in general, and among decision-makers within the criminal justice system and social services in particular.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13011-021-00409-3.

Circumstances, Postmortem Findings, Blood Concentrations and Metabolism in a Series of Methoxyacetylfentanyl Related Deaths

Methoxyacetylfentanyl is one of many fentanyl analogs available as new psychoactive substances. It have been encountered in both the European Union and the United States, and existing literature suggest that methoxyacetylfentanyl is around 3 to 5-fold less potent than fentanyl. The aim of the present work was to combine case information with blood concentrations and abundance of urinary metabolites to investigate the importance of these parameters for toxicological interpretation. Quantification of methoxyacetylfentanyl in femoral blood was performed by LC-MS/MS and urinary metabolites were analyzed by LC-QTOF-MS with and without hydrolysis with β-glucuronidase/arylsulfatase. For confirmation of identified metabolites, methoxyacetylfentanyl was incubated with hepatocytes for up to 5 hours and analyzed with the same method as the urine samples. In eleven postmortem cases (27 to 41 years old and including one female) methoxyacetylfentanyl was reported in femoral blood. The cause of death was intoxication by methoxyacetylfentanyl alone or in combination with other drugs in all but one case, where death was attributed to acute complications of an underlying heart disease but with possible contribution from methoxyacetylfentanyl. In total, 27 urinary metabolites were found, including eight glucuronides. Major biotransformations were O-demethylation, dealkylation to form the nor-metabolite, mono- and dihydroxylations of the phenethyl moiety, as well as combinations thereof. The most abundant metabolites in hydrolyzed urine included O-desmethyl-, O-desmethyl-phenethyl-hydroxy-, O-desmethyl-phenethyl-hydroxymethoxy- and nor-methoxyacetylfentanyl.Differences in the abundance of methoxyacetylfentanyl and its major metabolites could be interpreted to indicate fatal intoxications in abstinent or chronic users. We postulate that urinary concentrations of methoxyacetylfentanyl and two metabolites, in combination with the methoxyacetylfentanyl concentration in femoral blood, might be good indicators of the time between administration and death as well as prior use.

Heroin-Related Compounds and Metabolic Ratios in Postmortem Samples Using LC-MS-MS

Analysis of postmortem samples with the presence of morphine can sometimes be challenging to interpret. Tolerance complicates interpretation of intoxications and causes of death due to overlap in therapeutic and fatal concentrations. Determination of metabolites and metabolic ratios can potentially differentiate between abstinence, continuous administration, and perhaps time of administration. The purpose of this study was to (a) develop and validate a method for quantitation of morphine-3β-D-glucuronide, morphine-6β-D-glucuronide, normorphine, codeine-6β-D-glucuronide, norcodeine, codeine, 6-acetylmorphine, and ethylmorphine in urine using liquid chromatography–tandem mass spectrometry; (b) apply the method to opiate related deaths; (c) compare metabolic ratios in urine in different causes of death (CoD) and after different drug intakes and (d) compare heroin intoxications in rapid and delayed deaths. Validation parameters such as precision, bias, matrix effects, stability, process efficiency, and dilution integrity were assessed and deemed acceptable. Lower limits of quantitation ranged from 0.01–0.2 μg/mL for all analytes. Autopsy cases (n=135) with paired blood and urine samples were analyzed. Cases were divided into three groups based on CoD; opiate intoxication, intoxication with other drugs than opiates, and other CoD. The cases were classified by intake: codeine (n=42), heroin (n=36), morphine (n=49), and ethylmorphine (n=3). Five cases were classified as mixed intakes and excluded. Heroin intoxications (n=35) were divided into rapid (n=15) or delayed (n=20) deaths. Parent drug groups were compared using metabolic ratio morphine-3β-D-glucuronide/morphine and significant differences were observed between codeine vs morphine (p=0.005) and codeine vs heroin (p≤0.0001). Urine and blood concentrations, and metabolic ratios in rapid and delayed heroin intoxications were compared and determined a significant difference for morphine (p=0.001), codeine (p=0.009), 6-acetylmorphine (p=0.02) in urine, and morphine (p=0.02) in blood, but there was no significant difference (p=0.9) between metabolic ratios. Morphine-3β-D-glucuronide results suggested a period of abstinence prior to death in 25% of the heroin intoxications.

Prevalence and correlates of multiple non-fatal opioid overdoses among people who inject drugs who utilise needle syringe programs in Australia

BACKGROUND

Non-fatal overdose (NFOD) is a major cause of morbidity among people who inject drugs (PWID) and multiple NFOD is associated with increased risk of fatal overdose. Despite this, few studies have examined the prevalence and correlates of drug-specific multiple NFOD. The current study aimed to determine the prevalence and correlates of recent multiple non-fatal opioid overdose (NFOOD) among PWID who access needle syringe programs (NSPs) in Australia.

METHODS

The Australian Needle and Syringe Program Survey is conducted annually and was conducted at 46 sites across Australia in 2019. Participation involves completion of a self-administered questionnaire and a capillary dried blood spot for HIV and hepatitis C virus testing. In 2019, respondents who reported a minimum of one NFOOD in the previous 12 months (recent NFOOD) were asked to complete supplementary questions regarding their last NFOOD. Bivariate and multivariate logistic regression were used to determine factors independently associated with multiple recent NFOOD.

RESULTS

A total of 222 respondents reported recent NFOOD. Respondents were predominantly male (59%), one third (39%) were aged less than 39 years and 73% reported last injecting heroin at their last NFOOD. One in two respondents (48%, n = 107) reported multiple opioid overdoses (median 3, interquartile range 2-5). The odds of reporting multiple NFOOD were higher among respondents who reported injecting in a public location at their last NFOOD (adjusted odds ratio [AOR] 2.10, 95% CI 1.14-3.90, p = 0.018) and benzodiazepine use in the 12 h prior to NFOOD (AOR 2.74, 95% CI 1.50-4.99, p = 0.001).

CONCLUSIONS

Multiple NFOOD was prevalent among PWID who utilised NSPs who reported recent NFOOD. Public injecting and benzodiazepine use were associated with increased risk of multiple NFOOD, and there is a need for interventions specifically targeting PWID who report these high risk injecting practices.

Evaluation of an immunoassay procedure to measure 6-monoacetylmorphine

Introduction: 6-Monoacetylmorphine (6-MAM) is a specific metabolite of heroin. Thus, the presence of 6-MAM in urine is a definitive indication of heroin intake. The possibility of having an immunoassay procedure to measure 6-MAM would be a diagnosis tool to discriminate, among opiates-positive, those patients who have consumed heroin and those who have not.Methods: EMIT^® II Plus 6-Acetylmorphine Assay was used to measure 6-MAM in urine. The positive opiate screening results were confirmed at the Toxicology laboratory of our hospital by GC-MS.Results: This study includes 63 urine samples from subjects admitted to emergency department with suspicion of opiate consumption. Specificity was evaluated in the two groups of samples studied. In the first group all samples which resulted negative by opiate immunoassay (n = 33) were negative for 6-MAM immunoassay test. Thus, the specificity obtained for 6-MAM immunoassay in this group was 100%. Regarding the second specificity study, performed in positive samples by opiate immunoassay which were negative to 6 MAM by GC-MS, the specificity decreased down to 75%. In the study of sensitivity all samples confirmed as positive to 6-MAM by confirmatory method (GC-MS) resulted positive by the screening method, thus sensitivity obtained was 100%.Discussion: In this study no FN for 6-MAM was observed and therefore the new Emit^® II Plus 6- Acetylmorphine Assay procedure has a high NPV, thus a negative result with 6-MAM immunoassay practically excludes heroine consume. The positive results to 6-MAM by immunoassay should be confirmed by a more analytically specific method, such as GCMS.

Characteristics and circumstances of death related to gamma hydroxybutyrate (GHB)

Introduction: Gamma hydroxybutyrate (GHB) has gained substantial popularity as an illicit recreational drug. The current study aimed to: (1) determine the characteristics and circumstances of death of all recorded cases of GHB-related death in Australia, 2001-2019; (2) determine the toxicology of cases; and (3) determine major organ pathology.Methods: Retrospective study of all Australian cases in which GHB was a mechanism contributory to death retrieved from the National Coronial Information System (n = 74). Information was collected on cause of death, demographics, circumstances of death, toxicology and major organ pathology.Results: The mean age was 31.5 years and 70.3% were male. The predominant circumstance of death was accidental drug toxicity (79.7%), including five cases attributed to a combination of toxicity and natural disease. Other deaths were due to trauma (12.2%) and suicide (8.2%). The fatal incident overwhelmingly occurred in a home environment (82.4%). In all cases, GHB was consumed orally. The median GHB blood concentration was 210 mg/L (range 13-1350 mg/L), and was significantly higher in toxicity cases than others (258 vs. 98 mg/L, p < .01). Other substances were present in 92.2%, most commonly psychostimulants (64.1%), hypnosedatives (28.2%) and alcohol (20.3%). Resuscitation was attempted in 20.3% of cases. Acute pneumonia (36.7%) and aspiration of vomitus (30.6%) were common.Conclusions: The typical case was a young male, who swallowed GHB and used it with other substances, most commonly at home. While acute drug toxicity was the most common cause of death, there was a substantial minority due to trauma or suicide.

Protocol for a multi-site study of the effects of overdose prevention education with naloxone distribution program in Skåne County, Sweden

BACKGROUND

Continuously high rates of overdose deaths in Sweden led to the decision by the Skåne County to initiate the first regional take-home naloxone program in Sweden. The project aims to study the effect of overdose prevention education and naloxone distribution on overdose mortality in Skåne County. Secondary outcome measures include non-fatal overdoses and overdose-related harm in the general population, as well as cohort-specific effects in study participants regarding overdoses, mortality and retention in naloxone program.

METHODS

Implementation of a multi-site train-the-trainer cascade model was launched in June 2018. Twenty four facilities, including opioid substitution treatment units, needle exchange programs and in-patient addiction units were included for the first line of start-up, aspiring to reach a majority of individuals at-risk within the first 6 months. Serving as self-sufficient naloxone hubs, these units provide training, naloxone distribution and study recruitment. During 3 years, questionnaires are obtained from initial training, follow up, every sixth month, and upon refill. Estimated sample size is 2000 subjects. Naloxone distribution rates are reported, by each unit, every 6 months. Medical diagnoses, toxicological raw data and data on mortality and cause of death will be collected from national and regional registers, both for included naloxone recipients and for the general population. Data on vital status and treatment needs will be collected from registers of emergency and prehospital care.

DISCUSSION

Despite a growing body of literature on naloxone distribution, studies on population effect on mortality are scarce. Most previous studies and reports have been uncontrolled, thus not being able to link naloxone distribution to survival, in relation to a comparison period. As Swedish registers present the opportunity to monitor individuals and entire populations over time, conditions for conducting systematic follow-ups in the Swedish population are good, serving the opportunity to study the impact of large scale overdose prevention education and naloxone distribution and thus fill the knowledge gap.

TRIAL REGISTRATION

Naloxone Treatment in Skåne County - Effect on Drug-related Mortality and Overdose-related Complications, NCT03570099, registered on 26 June 2018.

Investigation of Fragmentation Pathways of Fentanyl Analogues and Novel Synthetic Opioids by Electron Ionization High-Resolution Mass Spectrometry and Electrospray Ionization High-Resolution Tandem Mass Spectrometry

The global drug market is characterized by the fast development of new psychoactive substances such as fentanyl analogues and novel synthetic opioids, the detection of which is complicated by the lack of appropriate quality control procedures and references. Herein, we analyze the fragmentation pathways and characteristic ions of 25 novel fentanyl analogues and 5 novel synthetic opioids by electron ionization (EI) and electrospray ionization (ESI) high-resolution mass spectrometry to provide a reference for the identification of these species. In the ESI mode, fentanyl analogues mainly undergo piperidine ring degradation, phenethyl and piperidine ring dissociation, and piperidine ring and amide moiety cleavage, while piperidine ring degradation and phenethyl and piperidine ring dissociation are the major pathways in the EI mode. The five novel synthetic opioids largely undergo amide group dissociation and N-cyclohexyl bond cleavage in the ESI mode. Thus, this work facilitates the detection and quantitation of fentanyl analogues and novel synthetic opioids or other substances with similar structures in forensic laboratories.

Take-Home Naloxone for the Emergency Interim Management of Opioid Overdose: The Public Health Application of an Emergency Medicine

Naloxone is a well-established essential medicine for the treatment of life-threatening heroin/opioid overdose in emergency medicine. Over two decades, the concept of 'take-home naloxone' has evolved, comprising pre-provision of an emergency supply to laypersons likely to witness an opioid overdose (e.g. peers and family members of people who use opioids as well as non-medical personnel), with the recommendation to administer the naloxone to the overdose victim as interim care while awaiting an ambulance. There is an urgent need for more widespread naloxone access considering the growing problem of opioid overdose deaths, accounting for more than 100,000 deaths worldwide annually. Rises in mortality are particularly sharp in North America, where the ongoing prescription opioid problem is now overlaid with a rapid growth in overdose deaths from heroin and illicit fentanyl. Using opioids alone is dangerous, and the mortality risk is clustered at certain times and contexts, including on prison release and discharge from hospital and residential care. The provision of take-home naloxone has required the introduction of new legislation and new naloxone products. These include pre-filled syringes and auto-injectors and, crucially, new concentrated nasal sprays (four formulations recently approved in different countries) with speed of onset comparable to intramuscular naloxone and relative bioavailability of approximately 40-50%. Choosing the right naloxone dose in the fentanyl era is a matter of ongoing debate, but the safety margin of the approved nasal sprays is superior to improvised nasal kits. New legislation in different countries permits over-the-counter sales or other prescription-free methods of provision. However, access remains uneven with take-home naloxone still not provided in many countries and communities, and with ongoing barriers contributing to implementation inertia. Take-home naloxone is an important component of the response to the global overdose problem, but greater commitment to implementation will be essential, alongside improved affordable products, if a greater impact is to be achieved.

Fentanyl depression of respiration: Comparison with heroin and morphine

BACKGROUND AND PURPOSE

Fentanyl overdose deaths have reached "epidemic" levels in North America. Death in opioid overdose invariably results from respiratory depression. In the present work, we have characterized how fentanyl depresses respiration, and by comparing fentanyl with heroin and morphine, the active breakdown product of heroin, we have sought to determine the factors, in addition to high potency, that contribute to the lethality of fentanyl.

EXPERIMENTAL APPROACH

Respiration (rate and tidal volume) was measured in awake, freely moving mice by whole body plethysmography.

KEY RESULTS

Intravenously administered fentanyl produced more rapid depression of respiration than equipotent doses of heroin or morphine. Fentanyl depressed both respiratory rate and tidal volume. Fentanyl did not depress respiration in μ-opioid receptor knockout mice. Naloxone, the opioid antagonist widely used to treat opioid overdose, reversed the depression of respiration by morphine more readily than that by fentanyl, whereas diprenorphine, a more lipophilic antagonist, was equipotent in reversing fentanyl and morphine depression of respiration. Prolonged treatment with morphine induced tolerance to respiratory depression, but the degree of cross tolerance to fentanyl was less than the tolerance to morphine itself.

CONCLUSION AND IMPLICATIONS

We propose that several factors (potency, rate of onset, lowered sensitivity to naloxone, and lowered cross tolerance to heroin) combine to make fentanyl more likely to cause opioid overdose deaths than other commonly abused opioids. Lipophilic antagonists such as diprenorphine may be better antidotes than naloxone to treat fentanyl overdose.

Circumstances of death of opioid users being treated with naltrexone

BACKGROUND AND AIMS

Naltrexone is an opioid antagonist used as a maintenance drug for the treatment of opioid dependence and in opioid withdrawal regimens. The current study aimed to: (1) determine the clinical characteristics and circumstances of death of people undergoing naltrexone treatment for opioid dependence; and (2) determine the blood toxicology of cases including naltrexone concentrations, the presence of other drugs and a comparison of morphine concentrations in the presence and absence of naltrexone.

DESIGN

Retrospective study of all deaths among people undergoing naltrexone treatment for opioid dependence retrieved from the National Coronial Information System, 2000-17.

SETTING

Australia-wide.

CASES

Seventy-four cases, with a mean age of 32.5 years; 81.1% male.

MEASUREMENTS

Information was collected on demographics, manner of death, naltrexone treatment history, toxicology and major organ pathology.

FINDINGS

Death was attributed to opioid toxicity in 86.5% of cases: accidental (79.7%), deliberate (6.8%). In 55.4% of all cases the decedent was maintained on oral naltrexone and 32.4% had a recent naltrexone implant. In five cases the decedent was undergoing opioid detoxification. Among those screened for naltrexone, naltrexone was present in the blood or urine of 52.5% (15.8% of oral maintenance cases, 85.7% of implant cases). Fourteen cases were known to have died from opioid toxicity with naltrexone present in their blood or urine. The median blood naltrexone concentrations were within the reported therapeutic range.

CONCLUSIONS

The primary cause of death among people undergoing naltrexone treatment for opioid dependence in Australia from 2000 to 2017 was opioid toxicity, the majority of cases having been maintained on oral naltrexone. Cases in which naltrexone was not detected indicate the importance of treatment compliance. Deaths due to opioid toxicity where naltrexone was present indicates the possibility of overdose while naltrexone medication is maintained.

"You can see those concentric rings going out": Emergency personnel's experiences treating overdose and perspectives on policy-level responses to the opioid crisis in New Hampshire

BACKGROUND

In parallel to a substantial increase in opioid overdose deaths in New Hampshire (NH), emergency personnel experienced an increase in opioid-related encounters. To inform public health responses to this crisis, insights into the experiences and perspectives of those emergency personnel who treat opioid-related overdoses are warranted.

AIMS

Systematically examine emergency personnel's experiences treating opioid overdoses and obtain their perspectives on policy-level responses to the opioid crisis in NH.

METHODS

Semi-structured qualitative interviews were conducted with 18 first responders [firefighters (n = 6), police officers (n = 6), emergency medical service providers (n = 6)] and 18 emergency department personnel employed in six NH counties. Interviews focused on emergency personnel's perspectives on fentanyl/heroin formulations, experiences treating overdoses, harm reduction strategies, and experiences with treatment referral. Interviews were audio recorded, transcribed verbatim, and analyzed using content analysis.

RESULTS

Emergency personnel cited the potency and inconsistency of fentanyl-laced heroin as primary drivers of opioid overdose. Increases in overdose-related encounters took a substantial emotional toll on emergency personnel, who described a range of responses including feelings of burnout, exhaustion, and helplessness. While some emergency personnel felt conflicted about the implementation of harm reduction strategies like syringe services programs, others emphasized the necessity of these services. Emergency personnel expressed frustration with barriers to treatment referral in the state and recommended immediate treatment access after overdose events.

CONCLUSIONS

Findings suggest that interventions addressing trauma and burnout are necessary to support emergency personnel, while expanded harm reduction and treatment access are critical to support those who experience opioid overdose in NH.

Characteristics and circumstances of synthetic cannabinoid-related death

Introduction: Synthetic cannabinoids are an emerging clinical and public health concern. The current study aimed to determine: (1) The characteristics and circumstances of death of all recorded cases of synthetic cannabinoid-related sudden or unnatural death in Australia, (2) The toxicology of cases and (3) Their major organ pathology.Methods: Retrospective study of all cases in Australia in which synthetic cannabinoid use was a mechanism contributory to death (n  =  55) retrieved from the National Coronial Information System (2000-2017). Information was collected on cause of death, demographics, drug use history, circumstances of death, toxicology and major organ pathology.Results: The mean age was 37.2 years and 91.1% were male. Causes of death comprised of accidental toxicity (38.2%), accidental toxicity/cardiovascular disease (9.1%), natural disease (20.0%), suicide (10.9%) and traumatic accident (10.9%). The most common clinical presentation proximal to death was sudden collapse (25.5%). Cardiovascular disease was prominent: severe atherosclerosis (20.0%), myocardial replacement fibrosis (18.0%), cardiomegaly (12.0%). The most frequent synthetic cannabinoids were the indazolecarboxemides (61.8%), most commonly AB-CHMINACA (38.2%). The most frequent other substances were alcohol (34.5%) and Δ⁹-THC (23.6%).Conclusions: AB-CHMINACA was the most commonly seen synthetic cannabinoid. There was a high representation of relatively older decedents and of older males in particular. While acute toxicity was the most common cause of death, cardiovascular disease was prominent.

Application of a chemiluminescence immunoassay system and GC/MS for toxicological investigations on skeletonized human remains

Hair, larvae and cardiac muscle, the only biological samples present on a skeletonized human body found in a rural area, were used for forensic toxicological analyses in order to determine possible causes of death. Since no information about the victim or the circumstances of death was available (except for the place where the corpse was found, known to be a gathering place for drug addicts), the first approach for the analysis of non-conventional matrices involved the screening of different classes of active principles, using a chemiluminescence-based screening assay designed for whole blood. The immunoassay test results showed positivity to amphetamines, cocaine and opiates on water/methanol extract from cardiac tissue, larvae and hair samples. Gas chromatography-mass spectrometry (GC/MS) analyses confirmed the immunoassay results, except for amphetamines. The minimal sample preparation (hydration and extraction in an ultrasonic bath), the reduced sample volume required for the analyses, together with the correctness of results as confirmed by GC/MS, showed the suitability of the screening test for forensic applications on non-conventional matrices. Quantitative analyses in GC/MS allowed the cause of death to be ascertained on the basis of the ratio between parent drugs and metabolites.

Methodological Complexities in Quantifying Rates of Fatal Opioid-Related Overdose

PURPOSE OF REVIEW

Effective responses to the US opioid overdose epidemic rely on accurate and timely drug overdose mortality data, which are generated from medicolegal death investigations (MDI) and certifications of overdose deaths. We identify nuances of MDI and certification of overdose deaths that can influence drug overdose mortality surveillance, as well as recent research, recommendations, and epidemiological tools for improved identification and quantification of specific drug involvement in overdose mortality.

RECENT FINDINGS

Death certificates are the foundation of drug overdose mortality surveillance. Accordingly, counts and rates of specific drug involvement in overdose deaths are only as accurate as the drug listed on death certificates. Variation in systematic approaches or jurisdictional office policy in drug overdose death certification can lead to bias in mortality rate calculations. Recent research has examined statistical adjustments to improve underreported opioid involvement in overdose deaths. New cause-of-death natural language text analysis tools improve quantification of specific opioid overdose mortality rates. Enhanced opioid overdose surveillance, which combines death certificate data with other MDI-generated data, has the potential to improve understanding of factors and circumstances of opioid overdose mortality.

SUMMARY

The opioid overdose crisis has brought into focus some of the limitations of US MDI systems for drug overdose surveillance and has given rise to a sense of urgency regarding the pressing need for improvements in our MDI data for public health action and research. Epidemiologists can stimulate positive changes in MDI data quality by demonstrating the critical role of data in guiding public health and safety decisions and addressing the challenges of accurate and timely overdose mortality measures with stakeholders. Education, training, and resources specific to drug overdose surveillance and analysis will be essential as the nation's overdose crisis continues to evolve.

Dynamics of heroin molecule inside the lipid membrane: a molecular dynamics study

Heroin, or diamorphine (C₂₁H₂₃NO₅), is an opium product used for various pharmaceutical and euphoric purposes. In this work, the molecular dynamics simulation study of the heroin inside the two lipid bilayers, dipalmitoylphosphatidylcholine (DMPC) and dipalmitoylphosphatidylcholine (DPPC) are presented. The whole study was conducted at three different temperatures. The location of the heroin drug, the nature of the diffusion, rotational correlation function and structural variation inside both lipid bilayers is studied. Moreover, the free energy of the solvation of the drug inside both lipid bilayers is calculated. It is found that during the whole molecular dynamics study, the drug locates at the center of both lipid membranes. The effect of the temperature is not seen at the drug location. The nature of the diffusion of the heroin drug is anomalous. The radius of gyration is calculated to study the structural variations of the heroin molecule inside both lipid bilayers. It is found that the heroin molecule does not change its structure at three temperatures. From the rotational correlation function, it is seen that the drug is more hindered for rotation inside the DPPC lipid bilayer as compared to the DMPC lipid bilayer. It is applicable for all three temperatures. The rotational correlation time of the drug is decreased while the temperature of the system is increased. In the case of DMPC, there is an abrupt change in rotational correlation time while the phase is changed.

Opioid Deaths in Milwaukee County, Wisconsin 2013-2017: The Primacy of Heroin and Fentanyl

Heroin and fentanyl are the overwhelming and increasing cause of opioid deaths in Milwaukee County, Wisconsin. We reviewed all drug and opioid deaths from 2013 to 2017 to delineate the specific opioid drugs involved and changes in their incidence. From 2013 to 2017, 980 deaths were due to opioids, rising from 184 in 2013 to 337 in 2017. In 2017, opioid deaths exceeded combined non-natural deaths from homicide and suicide. Illicit heroin and fentanyl/analogs caused 84% of opioid deaths and 80% of drug deaths, with no increase in deaths due to oral prescription drugs such as oxycodone and hydrocodone. Any approach to decreasing this dramatic increase in opioid deaths should first focus on interdicting the supply and cheap availability of these illicit opioids. Fentanyl and its analogs represent the most deadly opioids and the greatest threat to human life in our population.

Drug- and/or trauma-induced hyperthermia? Characterization of HSP70 and myoglobin expression

Introduction

Heat shock protein 70 (HSP70) expression could be discussed as an adaption that promotes repair and counteracts cell damage. Myoglobin is released upon muscle damage of several pathways. The purpose of the present study was to determine whether the expression of HSP70 in kidney, heart and brain and of myoglobin in the kidney were associated with the cause of death and the survival times after lethal intoxications with three of the drugs most widely used in our local area (Saxony, Germany) as well as after fatal traumatic brain injury (TBI).

Methods

We retrospectively collected kidney, heart and brain samples of 50 autopsy cases with toxicological proved lethal intoxication (main drugs methamphetamine, morphine, alcohol), 14 TBI cases and 15 fatalities with acute myocardial injury in age- and gender-matched compilations.

Results

Our main findings suggest that HSP70 is associated with hyperthermal and other stress factors of most cell populations. HSP70 expressions in kidney and heart muscle are useful for a differentiation between fatal intoxications and cases without toxicological influence (p < 0.05). There were significant differences in the cerebral expression patterns between methamphetamine- and morphine-associated deaths compared to alcohol fatalities (p < 0.05). An intensive staining of HSP70 in the pericontusional zone and the hippocampus after TBI (especially neuronal and vascular) was shown even after short survival times and may be useful as an additional marker in questions of vitality or wound age. A relevant myoglobin decoration of renal tubules was only shown for methamphetamine abuse in the study presented.

Conclusion

In sum, the immunohistochemical characteristics presented can be supportive for determining final death circumstances and minimal trauma survival times but are not isolated usefully for the detection of drug- or trauma-induced hyperthermia.

Using medical examiner case narratives to improve opioid overdose surveillance

BACKGROUND

Current opioid overdose mortality surveillance methods do not capture the complexity of the overdose epidemic. Most rely on death certificates, which may underestimate both opioid analgesic and heroin deaths. Categorizing deaths using other characteristics from the death record including route of drug administration may provide useful information to design and evaluate overdose prevention interventions.

METHODS

We reviewed California Electronic Death Reporting System records and San Francisco Office of the Chief Medical Examiner (OCME) toxicology reports and investigative case narratives for all unintentional opioid overdose deaths in San Francisco County from 2006 to 2012. We chose this time period because it encompassed a period of evolution in local opioid use patterns and expansion of overdose prevention efforts. We created a classification system for heroin-related and injection-related opioid overdose deaths and compared demographic, death scene, and toxicology characteristics among these groups.

RESULTS

We identified 816 unintentional opioid overdose deaths. One hundred fifty-two (19%) were standard heroin deaths, as designated by the OCME or by the presence of 6-monoacetylmorphine. An "expanded" classification for heroin deaths incorporating information from toxicology reports and case narratives added 20 additional heroin deaths (13% increase), accounting for 21% of all opioid deaths. Two hundred five deaths (25%) were injection-related, 60% of which were attributed to heroin. A combined classification of expanded heroin and injection-related deaths accounted for 31% of opioid overdose deaths during this period.

CONCLUSIONS

Using additional sources of information to classify opioid overdose cases resulted in a modest increase in the count of heroin overdose deaths but identified a substantial number of non-heroin injection-related opioid analgesic deaths. Including the route of administration in the characterization of opioid overdose deaths can identify meaningful subgroups of opioid users to enhance surveillance efforts and inform targeted public health programming including overdose prevention programs.

Clinical and Autopsy Characteristics of Fatal Methamphetamine Toxicity in Australia

Characteristics of death attributed solely to methamphetamine toxicity (MT, n = 93) by forensic pathologists were examined and compared to cases of multiple drug toxicity (MDT, n = 634). The mean age of MT cases was 36.7 years, and 86.0% were male. Strenuous activity was reported in 12.9%. The most common witness observations were: collapse (60.3%), difficulty in breathing (36.2%), and hyperthermia (27.6%). MT cases had higher blood methamphetamine (0.54 vs. 0.11 mg/L) and amphetamine (0.04 vs. 0.02 mg/L) concentrations and lower likelihoods for opioids (12.5% vs. 80.9%), hypnosedatives (27.3 vs. 60.7%), antidepressants (14.8 vs. 29.8%), and antipsychotics (9.1 vs. 19.7%). MT cases had significantly heavier hearts than MDT cases (423.4 vs. 385.8 g) and were more likely to have cardiomegaly (37.1 vs. 20.4%) and replacement fibrosis (25.7 vs. 14.5%). The clinical picture was of a sudden cardiac event in a middle-aged man with a high methamphetamine concentration. Cardiovascular signs of heavy methamphetamine use are frequently seen.

Twenty years of take-home naloxone for the prevention of overdose deaths from heroin and other opioids-Conception and maturation

BACKGROUND

Opioid overdose is a major cause of mortality, but injury and fatal outcomes can be prevented by timely administration of the opioid antagonist naloxone. Pre-provision of naloxone to opioid users and family members (take-home naloxone, THN) was first proposed in 1996, and WHO Guidelines were issued in 2014. While widespread in some countries, THN is minimally available or absent elsewhere. This review traces the development of THN over twenty years, from speculative harm reduction proposal to public health strategy.

METHOD

Medline and PsycINFO were searched for peer-reviewed literature (1990-2016) using Boolean queries: 1) "naloxone OR Narcan"; 2) "(opioid OR opiate) AND overdose AND prevention". Grey literature and specialist websites were also searched. Data were extracted and synthesized as narrative review, with key events presented as chronological timeline.

RESULTS

Results are presented in 5-year intervals, starting with the original proposal and THN pilots from 1996 to 2001. Lack of familiarity with THN challenged early distribution schemes (2001-2006), leading to further testing, evaluation, and assessment of challenges and perceived medicolegal barriers. From 2006-2011, response to social and legal concerns led to the expansion of THN programs; followed by high-impact research and efforts to widen THN availability from 2011 to 2016.

CONCLUSIONS

Framed as a public health tool for harm reduction, THN has overcome social, clinical, and legal barriers in many jurisdictions. Nonetheless, the rising death toll of opioid overdose illustrates that current THN coverage is insufficient, and greater public investment in overdose prevention will be required if THN is to achieve its full potential impact.

Pharmacokinetics of concentrated naloxone nasal spray over first 30 minutes post-dosing: analysis of suitability for opioid overdose reversal

BACKGROUND AND AIMS

Lack of non-injectable naloxone formulations has impeded widespread take-home provision for the prevention of heroin/opioid overdose deaths. For non-injectable formulations that are finally being investigated, rapid onset of action and sufficient bioavailability will be vital. We present analysis of data from a study of concentrated naloxone nasal spray formulations. Our aims are: to assess (1) pharmacokinetic properties and (2) suitability for overdose reversal in terms of naloxone absorption within 30 minutes post-dosing.

DESIGN AND INTERVENTIONS/COMPARATOR

Open-label, randomized, four-way cross-over Latin-square pharmacokinetic study of naloxone administration by three routes: intranasal at two doses (8 mg/0.4 ml, 16 mg/0.4 ml) versus sublingual (16 mg/ml) versus intravenous reference (1 mg/ml).

SETTING

Clinical Pharmacology Unit at The Ohio State University (Columbus, OH, USA).

PARTICIPANTS

Twelve healthy volunteers (age 20-41; seven female).

MEASUREMENTS

From blood plasma naloxone concentrations, (1) standard pharmacokinetic parameters, including maximum plasma concentration (C_max ) and mean absolute bioavailability (F%, relative to intravenous injection), were determined; as well as (2) partial area under the curve (AUC) values, t_max (time to maximum plasma concentration) and t_50% (time to 50% of maximum plasma concentration) as measures of early absorption.

FINDINGS

(1) Bioavailability was F% = 25-28% for intranasal naloxone. Sublingual had low bioavailability (F% = 2%) and was not considered further. Mean C_max values for 8 mg (12.83 ng/ml) and 16 mg (18.25 ng/ml) intranasal exceeded 1 mg intravenous (9.64 ng/ml) naloxone. (2) Following intranasal administration, t_50% was reached within 8 minutes and t_max within 20 minutes. Mean naloxone absorption from dosing to 30 minutes (AUC₃₀ ) was greater following 8 mg (4.17 h × ng/ml) and 16 mg (5.91 h × ng/ml) intranasal than following 1 mg intravenous (1.70 h × ng/ml) administration.

CONCLUSIONS

Concentrated naloxone nasal spray has a promising pharmacokinetic profile, with substantial bioavailability. Its early absorption time-course suggests that concentrated nasal naloxone is suitable for emergency administration in the community, where rapid restoration of respiratory function is essential for opioid overdose reversal.

Naloxone for heroin, prescription opioid, and illicitly made fentanyl overdoses: Challenges and innovations responding to a dynamic epidemic

Community-based overdose prevention programs first emerged in the 1990's and are now the leading public health intervention for overdose. Key elements of these programs are overdose education and naloxone distribution to people who use opioids and their social networks. We review the evolution of naloxone programming through the heroin overdose era of the 1990's, the prescription opioid era of the 2000's, and the current overdose crisis stemming from the synthetic opioid era of illicitly manufactured fentanyl and its analogues in the 2010's. We present current challenges arising in this new era of synthetic opioids, including variable potency of illicit drugs due to erratic adulteration of the drug supply with synthetic opioids, potentially changing efficacy of standard naloxone formulations for overdose rescue, potentially shorter overdose response time, and reports of fentanyl exposure among people who use drugs but are opioid naïve. Future directions for adapting naloxone programming to the dynamic opioid epidemic are proposed, including scale-up to new venues and social networks, new standards for post-overdose care, expansion of supervised drug consumption services, and integration of novel technologies to detect overdose and deliver naloxone.

Frequency and severity of non-fatal opioid overdoses among clients attending the Sydney Medically Supervised Injecting Centre

BACKGROUND

Pharmaceutical opioid overdose rates have increased in recent years. The current study aimed to compare rates per 1000 injections of non-fatal overdose after heroin or oxycodone injection, and their comparative clinical severity.

METHODS

Analysis of prospectively collected data from the Sydney Medically Supervised Injecting Centre (MSIC). Severity of overdose was measured using the Glasgow Coma Scale, oxygen saturation levels, and the administration of naloxone.

RESULTS

Heroin overdoses occurred at three times the rate of oxycodone overdoses (12.7 v 4.1 per 1000 injections). Heroin overdoses appeared to be more severe than oxycodone overdoses, with higher levels of compromised consciousness (31 v 18%) and severe respiratory depression (67 v 48%), but there were no differences in naloxone doses (20 v 17%). Concurrent use of other depressants at the time of overdose was also associated with compromised consciousness, and the need for naloxone.

CONCLUSIONS

Heroin overdoses occurred at a greater rate than oxycodone overdoses, and had more severe clinical indicators.

Characterization and Management of Patients with Heroin versus Nonheroin Opioid Overdoses: Experience at an Academic Medical Center

STUDY OBJECTIVES

To characterize the differences between patients who had heroin and nonheroin opioid overdoses and to determine whether there were any significant differences in their management with regard to the naloxone use.

DESIGN

Retrospective cohort study.

SETTING

Large academic medical center.

PATIENTS

A total of 923 patients admitted to the medical center who were identified for overdose by heroin or other opiate-related narcotics between January 2010 and September 2015; 480 patients experienced a nonheroin opioid overdose event, and 443 patients experienced a heroin overdose event.

MEASUREMENTS AND MAIN RESULTS

Patients presenting with heroin overdose tended to be younger and male, with higher rates of hepatitis C virus (HCV) infection compared with those presenting with nonheroin opioid overdose (p<0.05). Patients in the heroin group were also more likely to have a previous overdose event, history of injection drug use, and history of prescription opioid abuse compared with the nonheroin group (p<0.05). Those presenting with heroin overdose were more likely to receive naloxone in the prehospital setting (p<0.05) but were less likely to receive naloxone once admitted (p<0.05). Patients with nonheroin opioid overdoses required more continuous infusions of naloxone (p<0.05) and admission to the intensive care unit (p<0.05). Of all 923 patients, 178 (19.3%) had a repeat admission for any reason, and 70 (7.6%) were readmitted over the course of the study period for another overdose event with the same drug. The proportion of patients presenting with a heroin overdose steadily increased from 2010-2015; the number of patients presenting to the emergency department with nonheroin opioid overdoses steadily decreased. As rates of heroin overdose increased each year, the incidence of HCV infection increased dramatically.

CONCLUSION

This study indicates that the incidence of heroin overdoses has significantly increased over the last several years, and the rates of HCV infection 4-fold since the start of the study period. Patients admitted for nonheroin opioid overdose were more likely to be admitted to the hospital and intensive care unit compared with those admitted for heroin overdose. The rise in overdose events only further illustrates a gap in our understanding of the cycle of addiction, drug abuse, and overdose events.