Trends in drug overdose deaths in England and Wales 1993-98: methadone does not kill more people than heroin

Trends in Fatal Poisoning Among Drug Users in France From 2011 to 2021: An Analysis of the DRAMES Register

Importance

The DRAMES (Décès en Relation avec l'Abus de Médicaments Et de Substances) register is a database of drug-related deaths with the aim of identifying the psychoactive substances associated with and estimating the trends in these deaths. Our novel approach is based on the collection of data on all deaths for which toxicology experts have performed analyses.

Objective

To describe drug-related deaths in France and report trends over an 11-year period.

Design, Setting, and Participants

This case series used a national register to assess 4460 drug-related deaths that occurred from 2011 to 2021 in France. Data analyses were performed from January 1, 2012, to December 31, 2022.

Main Outcomes and Measures

Demographic characteristics; medical and substance abuse history; forensic autopsy findings; and toxicology reports.

Results

Among the 4460 deceased individuals (mean [SD] age, 37.8 [10.5] years), the mortality rate was highest among men (sex ratio, 4.4:1). Of the deaths involving a single or predominant drug, the legal substitution product, methadone, was the leading cause of death during the entire study period, ahead of heroin-44.7% and 35.9% for methadone vs 15.8% and 21.8% for heroin in 2011 and 2021, respectively. Between 2011 and 2021, most of the drug-related deaths shifted from licit to illicit drugs, and statistically significant variations were found for buprenorphine, cocaine, heroin, methadone, and other licit opioids. Deaths related to polydrug use increased from 23.2% in 2011 to 30.6% in 2021. In this context, opioids remained associated with most deaths, with at least 1 opioid being involved in approximately 9 of 10 cases (85.9%) in 2021. However, the main trend was the dramatic increase in drug combinations with cocaine, from less than one-third of cases in 2011 (30.8%) to more than half in 2021 (57.8%).

Conclusions and Relevance

This case series assessment of 4460 drug-related deaths found that opioids used alone or in combination were the main contributor to drug-related deaths, despite having a lower prevalence than other drugs. This finding is similar to that of other countries; however, in France licit methadone was the leading cause of opioid-related deaths (ahead of heroin) during the study period. Deaths associated with use of cannabis, new psychoactive substances, and stimulants (including amphetamine-type stimulants and cocaine, especially in combination) have increased and should be closely monitored.

Perceptions and Experiences of Methadone Maintenance Treatment: A Qualitative Descriptive Research Study

Over the past 10 years, there has been a consistent increase in opioid use, which has resulted in an increase in methadone maintenance treatment (MMT). With retention in MMT being a key factor, to understand the process of retention, it is important to better understand individual perceptions and experiences. Little research in Ottawa, Ontario, has addressed the perspective of MMT from people enrolled in MMT; therefore, nursing-based research was undertaken. The objective was to understand the process and experiences associated with MMT from the perspective of persons who are enrolled in treatment. Twelve participants were engaged in semistructured interviews. These participants described that, although MMT can positively affect the people who use such a treatment option, multiple barriers, including social perceptions, physical environment, and healthcare delivery practices, continue to affect MMT initiation and delivery.

Five-year standardised mortality ratios in a cohort of homeless people in Dublin

OBJECTIVE

To calculate standardised mortality ratios (SMRs) for a cohort of homeless people in the Dublin region over a 5-year period and to examine leading causes of death.

SETTING

Homeless services reporting deaths from homeless persons in their care across the Dublin Homeless Region.

METHODS

Death data among people who experience homelessness was acquired from the Dublin Region Homeless Executive (2011-2015) and validated from both death certificates and records from the Dublin Coroner's Office.

PARTICIPANTS

Two hundred and nine deaths were recorded; of these 201 were verified (n=156 males, 77.6%). Deaths that could not be verified by certificate or coroners record were excluded from the study.

RESULTS

SMRs were 3-10 times higher in homeless men and 6-10 times higher in homeless women compared with the general population. Drug and alcohol-related deaths were the leading cause of death, accounting for 38.4% of deaths in homeless individuals. These were followed by circulatory (20%) and respiratory causes (13%).

CONCLUSION

Mortality rates among homeless persons are exceptionally high. Services and programmes, particularly housing and those targeting overdose and alcoholism, are urgently needed to prevent premature mortality in this vulnerable population.

Examining Fatal Opioid Overdoses in Marion County, Indiana

Drug-related overdoses are now the leading injury-related death in the USA, and many of these deaths are associated with illicit opioids and prescription opiate pain medication. This study uses multiple sources of data to examine accidental opioid overdoses across 6 years, 2010 through 2015, in Marion County, IN, an urban jurisdiction in the USA. The primary sources of data are toxicology reports from the county coroner, which reveal that during this period, the most commonly detected opioid substance was heroin. During the study period, 918 deaths involved an opiod, and there were significant increases in accidental overdose deaths involving both heroin and fentanyl. In order to disentangle the nature and source of opioid overdose deaths, we also examine data from Indiana's prescription drug monitoring program and the law enforcement forensic services agency. Results suggest that there have been decreases in the number of opiate prescriptions dispensed and increases in law enforcement detection of both heroin and fentanyl. Consistent with recent literature, we suggest that increased regulation of prescription opiates reduced the likelihood of overdoses from these substances, but might have also had an iatrogenic effect of increasing deaths from heroin and fentanyl. We discuss several policy implications and recommendations for Indiana.

Heroin overdose

BACKGROUND AND AIMS

This narrative review aims to provide a brief history of the development of the heroin overdose field by discussing a selection of major 'classics' from the latter part of the 20th century.

METHODS

Papers considered landmarks were selected from 1972, 1977, 1983, 1984 and 1999.

RESULTS

Findings of earlier works suggest much of what later research was to demonstrate. These include arguing that overdoses occurred primarily among tolerant older users, that most 'overdose' deaths involved low morphine concentrations, that most overdoses involve polypharmacy, that drug purity has only a moderate influence on overdose rates and that instant death following heroin administration is rare.

CONCLUSIONS

Landmark studies of heroin overdose from the 1970s, 1980s and 1990s laid the foundations for subsequent overdose research, mainly by identifying the major demographic characteristics of overdose cases, risk factors, survival times and behaviours at overdose events.

Research Note — Review of Corrections-Based Therapy for Opiate-Dependent Patients: Implications for Buprenorphine Treatment among Correctional Populations

Inmates with a history of opiate dependence represent a substantial proportion of the correctional population in the United States. Opiate use has negative consequences for both the inmate and society, including increased recidivism rates, increased infectious disease prevalence, avoidable emergency room use, decreased access to primary care services, and overdose. While there have been great successes in community-based treatment of opiate dependence, these successes have not yet been achieved in correctional settings. This paper reviews the pharmacological treatment options for opiate-dependent inmates, along with potential application for community-to-correctional approaches. The recent approval by the Food and Drug Administration (FDA) of physician-prescribed buprenorphine and the new opportunities it presents to corrections-based treatment are also explored in depth. Successful implementation of such strategies is likely to result in desirable health and social outcomes for both the inmate and the community at large.

Risk of mortality on and off methadone substitution treatment in primary care: a national cohort study

AIM

To assess whether risk of death increases during periods of treatment transition, and investigate the impact of supervised methadone consumption on drug-related and all-cause mortality.

DESIGN

National Irish cohort study.

SETTING

Primary care.

PARTICIPANTS

A total of 6983 patients on a national methadone treatment register aged 16-65 years between 2004 and 2010.

MEASUREMENT

Drug-related (primary outcome) and all-cause (secondary outcome) mortality rates and rate ratios for periods on and off treatment; and the impact of regular supervised methadone consumption.

RESULTS

Crude drug-related mortality rates were 0.24 per 100 person-years on treatment and 0.39 off treatment, adjusted mortality rate ratio 1.63 [95% confidence interval (CI) = 0.66-4.00]. Crude all-cause mortality rate per 100 person-years was 0.51 on treatment versus 1.57 off treatment, adjusted mortality rate ratio 3.64 (95% CI = 2.11-6.30). All-cause mortality off treatment was 6.36 (95% CI = 2.84-14.22) times higher in the first 2 weeks, 9.12 (95% CI = 3.17-26.28) times higher in weeks 3-4, compared with being 5 weeks or more in treatment. All-cause mortality was lower in those with regular supervision (crude mortality rate 0.60 versus 0.81 per 100 person-years) although, after adjustment, insufficient evidence exists to suggest that regular supervision is protective (mortality rate ratio = 1.23, 95% CI = 0.67-2.27).

CONCLUSIONS

Among primary care patients undergoing methadone treatment, continuing in methadone treatment is associated with a reduced risk of death. Patients' risk of all-cause mortality increases following treatment cessation, and is highest in the initial 4-week period.

Risk Factors for Mortality and Endotracheal Intubation after Methadone Intoxication

This was a retrospective chart review to evaluate various risk factors associated with in-hospital mortality and intubation risk in acute methadone overdose. All patients admitted to an academic hospital in Tehran, Iran, during a 10-year period (2000-2009) constituted the study sample. Exclusion criteria were significant comorbidities and age under 18 years. Outcome variables were in-hospital mortality and being intubated during admission. A total of 802 patients were enrolled in the study. There were 15 (1.8%) deaths due to methadone overdose or its complications. The number of yearly admissions was 15 patients in 2000, 16 in 2001, 16 in 2002, 18 in 2003, 23 in 2004, 38 in 2005, 59 in 2006, 110 in 2007, 206 in 2008 and 301 in 2009. Based on logistic regression analysis, the most important independent variable predicting mortality was length of admission in toxicology ward [OR (95% CI): 1.6 (1.1-2.3)]. For the prediction of intubation, independent variables were Glasgow Coma Scale (GCS) score of 5-9 [OR (95% CI): 356.5 (9.8-12907.4)] in the emergency department (ED), miosis in the ED [356.9 (1.4-87872.5)] and respiratory rate in the ED [1.5 (1.1-2.1)]. Linear regression model for length of hospitalization showed patient age as the most important variable for prediction of this outcome. Despite a relatively low mortality rate, the increasing number of methadone-poisoned patients requires special attention to this common intoxication. Careful disposition of patients from ED to ordinary wards or intensive care units and also from higher to lower levels of care should be considered in methadone overdose.

The relative risk of fatal poisoning by methadone or buprenorphine within the wider population of England and Wales

OBJECTIVE

To examine the population-wide overdose risk emerging from the prescription of methadone and buprenorphine for opioid substitution treatment in England and Wales.

DESIGN

Retrospective administrative data study.

SETTING

National databases for England and Wales.

PARTICIPANTS/CASES

Drug-related mortality data were drawn from the Office for National Statistics, and prescription data for methadone and buprenorphine were obtained from the National Health Service for the years 2007-2012. During this 6-year period, a total of 2366 methadone-related deaths and 52 buprenorphine-related deaths were registered, corresponding to 17,333,163 methadone and 2,602,374 buprenorphine prescriptions issued. The analysis encompassed poisoning deaths among members of the wider population of England and Wales who consumed, but were not prescribed these medications, in addition to patients prescribed methadone or buprenorphine.

MAIN OUTCOME MEASURES

Mortality risk: substance-specific overdose rate per 1000 prescriptions issued; relative risk ratio of methadone in relation to buprenorphine.

RESULTS

During the years 2007-2012, the pooled overdose death rate was 0.137/1000 prescriptions of methadone, compared to 0.022/1000 prescriptions of buprenorphine (including buprenorphine-naloxone). The analysis generated a relative risk ratio of 6.23 (95% CI 4.79 to 8.10) of methadone in relation to buprenorphine. UK Borders Agency data were taken into consideration and revealed that only negligible amounts of methadone and buprenorphine were seized on entering UK territory between 2007 and 2012, suggesting domestic diversion.

CONCLUSIONS

Our analysis of the relative safety of buprenorphine and methadone for opioid substitution treatment reveals that buprenorphine is six times safer than methadone with regard to overdose risk among the general population. Clinicians should be aware of the increased risk of prescribing methadone, and tighter regulations are needed to prevent its diversion.

Opiate- and cocaine-related fatal overdoses in Luxembourg from 1985 to 2011: a study on gender differences

BACKGROUND/AIM

We analysed gender differences in national fatal overdose (FOD) cases related to opiates and cocaine use between 1985 and 2011 (n = 340).

METHODS

Cross-examination of national data from law enforcement and drug use surveillance sources and of forensic evidence. Bivariate and logistic regression analysis of male/female differences according to sociodemographics, forensic evidence and drug use trajectories.

RESULTS

The burden of deaths caused by FOD on the general national mortality was higher for men (PMR/100=0.55) compared with women (PMR/100=0.34). Compared with their male peers, women were younger at the time of death (t=3.274; p=0.001) and showed shorter drug use careers (t=2.228; p=0.028). Heroin use was recorded more frequently in first drug offences of female victims (AOR=6.59; 95% CI 2.97-14.63) and according to forensic evidence, psychotropic prescription drugs were detected to a higher degree in females (AOR=2.019; 95% CI 1.065-3.827).

CONCLUSION

The time window between the onset of illicit drug use and its fatal outcome revealed to be shorter for women versus men included in our study. Early intervention in female drug users, routine involvement of first-line healthcare providers and increased attention to use of poly- and psychotropic prescription drugs might contribute to prevent premature drug-related death and reduce gender differences.

Take-home emergency naloxone to prevent heroin overdose deaths after prison release: rationale and practicalities for the N-ALIVE randomized trial

The naloxone investigation (N-ALIVE) randomized trial commenced in the UK in May 2012, with the preliminary phase involving 5,600 prisoners on release. The trial is investigating whether heroin overdose deaths post-prison release can be prevented by prior provision of a take-home emergency supply of naloxone. Heroin contributes disproportionately to drug deaths through opiate-induced respiratory depression. Take-home emergency naloxone is a novel preventive measure for which there have been encouraging preliminary reports from community schemes. Overdoses are usually witnessed, and drug users themselves and also family members are a vast intervention workforce who are willing to intervene, but whose responses are currently often inefficient or wrong. Approximately 10% of provided emergency naloxone is thought to be used in subsequent emergency resuscitation but, as yet, there have been no definitive studies. The period following release from prison is a time of extraordinarily high mortality, with heroin overdose deaths increased more than sevenfold in the first fortnight after release. Of prisoners with a previous history of heroin injecting who are released from prison, 1 in 200 will die of a heroin overdose within the first 4 weeks. There are major scientific and logistical challenges to assessing the impact of take-home naloxone. Even in recently released prisoners, heroin overdose death is a relatively rare event: hence, large numbers of prisoners need to enter the trial to assess whether take-home naloxone significantly reduces the overdose death rate. The commencement of pilot phase of the N-ALIVE trial is a significant step forward, with prisoners being randomly assigned either to treatment-as-usual or to treatment-as-usual plus a supply of take-home emergency naloxone. The subsequent full N-ALIVE trial (contingent on a successful pilot) will involve 56,000 prisoners on release, and will give a definitive conclusion on lives saved in real-world application. Advocates call for implementation, while naysayers raise concerns. The issue does not need more public debate; it needs good science.

Tramadol induces conditioned place preference in rats: interactions with morphine and buprenorphine

Surveys and drug surveillance have demonstrated that the abuse liability of tramadol is considerably low in the general population but appears to be higher in opiate addicts, and this difference could attribute to the poly-drug abuse of opioid addicts, although this hypothesis has not been tested in the laboratory. The present study examined the interactions between tramadol and a full μ opioid receptor agonist morphine or a partial μ opioid receptor agonist buprenorphine in a conditioned place preference (CPP) paradigm in rats. Rats were conditioned with tramadol (2-54 mg/kg, i.p.), morphine (0.125-8 mg/kg, s.c.), buprenorphine (0.01-0.316 mg/kg, s.c.) or a combination of a subeffective dose of tramadol (2mg/kg) with a subeffective dose of morphine or buprenorphine and the CPP effect was measured. The retention of CPP effect was also examined. Tramadol, morphine and buprenorphine all produced a dose-dependent and significant CPP. A smaller dose of tramadol (2mg/kg) enhanced morphine- and buprenorphine-induced CPP and shifted the dose-effect curves of both drugs leftward. In addition, the combination of tramadol with morphine or buprenorphine prolonged the retention of CPP. These findings indicate that tramadol potentiates the rewarding effects of morphine or buprenorphine largely in an additive manner and support the general contention that tramadol has relatively low abuse liability.

Influence of war on quantitative and qualitative changes in drug-induced mortality in Split-Dalmatia County, Croatia

Aim

To study drug-induced mortality and characteristics of overdose deaths in the war (1991-1995), pre-war (1986-1990), and post-war period (1996-2000) in Split-Dalmatia County.

Methods

We retrospectively searched through Databases of the Department of Forensic Medicine, University Hospital Split, the national register of death records, the archives of the Split-Dalmatia County Police, and the Register of Treated Drug Addicts of the Croatian National Institute of Public Health, covering the period from 1986 to 2000, according to drug poisoning codes IX and X of the International Classification of Diseases. The indicators were statistically analyzed.

Results

There were 146 registered drug-induced deaths, with 136 (93%) deceased being men. The median age of all cases was 27 years (interquartile range 8). Most of them were single (70.6%), unemployed (44.6%), and secondary school graduates (69.2%). In the war period, there were 4.8 times more deaths than in the pre-war period (P = 0.014), and in the post-war period there were 5.2 times more deaths than in the pre-war period (P = 0.008). The most common site of death was the deceased person’s home. The toxicological analyses showed that 59 (61%) deaths were heroin related, alcohol use was found in 62 cases (42.5%), and multi-substance use was found in more than a half of the cases. In 133 (91.1%) cases, deaths were classified as unintentional, whereas 13 (8.9%) were classified as suicides.

Conclusion

The war, along with other risk factors, contributed to unfavorable developments related to drug abuse in Split-Dalmatia County, including the increase in the drug-induced mortality rate.

Elevated overdose mortality rates among First Nations individuals in a Canadian setting: a population-based analysis

AIMS

To determine the total burden of illicit drug overdose mortality over the study period in the province of British Columbia and investigate possible population-level determinants by estimating rates among subgroups including First Nations individuals.

DESIGN

Review of coroner case files.

SETTING

The province of British Columbia, Canada.

PARTICIPANTS

Individuals dying from an illicit drug overdose between 2001 and 2005.

MEASUREMENTS

Age-adjusted mortality rates, standardized mortality ratios (SMR) and years of potential life lost (YPLL), stratified by major population groups.

FINDINGS

Over the study period, 909 individuals died from illicit drug overdoses, including 104 (11.4%) First Nations individuals. Compared to the general population, First Nations males and females suffered from substantially elevated SMR and YPLL. In a multivariate logistic regression analysis, First Nations deaths were significantly more likely to be among women, related to injection drug use and to have occurred in the Downtown Eastside area of Vancouver, the local epicentre of human immunodeficiency virus infection and open drug use (all P< 0.05).

CONCLUSIONS

This report found highly elevated overdose death rates and levels of premature mortality among First Nations Canadians in British Columbia compared to the general population. While previously unidentified, these findings are consistent with the poorer population health profile of First Nations Canadians. Although further research is needed to identify the causes of the elevated death rates, our findings support increased availability of evidence-based overdose prevention measures.

Impact of supervision of methadone consumption on deaths related to methadone overdose (1993-2008): analyses using OD4 index in England and Scotland

OBJECTIVE

To evaluate the impact of introduction of supervision of methadone dosing on deaths related to overdose of methadone in Scotland and England between 1993 and 2008 while controlling for increased prescribing of methadone.

DESIGN

Analysis of annual trends in deaths related to overdose of methadone in relation to defined daily doses of methadone prescribed.

SETTING

Scotland and England. Population Deaths in which methadone was coded as the only drug involved or as one of the drugs implicated.

MAIN OUTCOME MEASURE

Annual OD4-methadone index (number of deaths with methadone implicated per million defined daily doses of methadone prescribed in that year).

RESULTS

OD4-methadone declined substantially over the four epochs of four years between 1993 and 2008. It decreased significantly (P<0.05) in 10 of 12 epoch changes: in Scotland from 19.3 (95% confidence interval 15 to 24) to 4.1 (2.8 to 5.4) and finally to 3.0 (2.4 to 3.5) for methadone only deaths (and from 58 to 29 to 14 for deaths with any mention of methadone); in England from 27.1 (25 to 29) to 24.8 (23 to 27) and finally to 5.8 (5.3 to 6.3) for methadone only deaths (and from 46 to 42 to 12 for deaths with any mention of methadone). The decreases in OD4-methadone were closely related to the introduction of supervised dosing of methadone in both countries, first in Scotland (1995-2000) and later in England (1999-2005). These declines occurred over periods of substantial increases in prescribing of methadone (18-fold increase in defined daily doses per million population annually in Scotland and sevenfold increase in England).

CONCLUSIONS

Introduction of supervised methadone dosing was followed by substantial declines in deaths related to overdose of methadone in both Scotland and England. OD4-methadone index analyses, controlled for substantial increases in methadone prescribing in both countries, identified at least a fourfold reduction in deaths due to methadone related overdose per defined daily dose (OD4-methadone) over this period.

Development of a coroner-based surveillance system for drug-related deaths in Los Angeles county

Existing data sources do not provide comprehensive and timely information to adequately monitor drug-related mortality in Los Angeles County. To fill this gap, a surveillance system using coroner data was developed to examine patterns in drug-related deaths. The coroner provided data on all injury deaths in Los Angeles County. A list of keywords that indicate a death was caused by drug use was developed. The cause of death variables in the coroner data were searched for mentions of one of the keywords; if a keyword was detected, that death was classified as drug related. The effectiveness of the keyword list in classifying drug-related deaths was evaluated by matching records in the coroner death data to records in the state death files. Then, the drug-related deaths identified using the keywords were compared to drug-related deaths in the state mortality files identified using International Classification of Death codes. Toxicological test results were used to categorize drug-related deaths based on the type and legality of the drug(s) ingested. Mortality rates were calculated for each category of drug and legal status and for different demographic groups. Compared to the gold standard state mortality files, the coroner data had a sensitivity of 95.6% for identifying drug-related deaths. Over three quarters of all drug-related deaths tested positive for opiates and/or stimulants. Males, Whites, and 35-54-year-olds each accounted for more than half of all drug-related deaths. The surveillance of drug-related deaths using coroner data has several advantages: data are available in a timely fashion, the data include information about the specific substances each victim ingested, and the data can be broken down to compare mortality among specific subpopulations.

The comparative toxicology and major organ pathology of fatal methadone and heroin toxicity cases

In order to determine the comparative toxicology and systemic disease of cases of death due to methadone and heroin toxicity, 1193 coronial cases of opioid overdose that occurred in New South Wales, Australia between 1 January 1998 and 31 December 2007 were inspected. These comprised 193 cases in which cause of death involved methadone toxicity (METH) and 1000 cases in which cause of death involved heroin toxicity in the absence of methadone (HER). METH cases were significantly more likely to have benzodiazepines (63.7% vs. 32.2%), and less likely to have alcohol (23.6% vs. 42.7%) detected. METH cases were significantly more likely to be diagnosed with pre-existing systemic pathology (94.3% vs. 79.9%), and multiple organ system pathology (68.8% vs. 41.4%). Specifically, METH cases were more likely to have cardiac (58.9% vs. 34.5%), pulmonary (53.6% vs. 30.9%), hepatic (80.7% vs. 62.8%) and renal (25.0% vs. 9.5%) disease. Given the notable differences in toxicology and disease patterns, great caution appears warranted in prescribing benzodiazepines to methadone users, and regular physical examinations of methadone treatment patients would appear clinically warranted.

Problem drug use the public health imperative: what some of the literature says

Background

With more than 200,000 problem drug users is contact with structured treatment services in England the public health imperative behind drug treatment is great. Problem drug use for many is a chronic and relapsing condition, where "cure" is often neither a reasonable or appropriate expectation and it can further be argued that in these circumstances problem drug use is no different from any number of chronic and enduring health conditions that are managed in the health care system and therefore should be conceptualised as such.

Discussion

A public health approach to drug treatment emphasises the need for drug users in or accessing treatment, to reduce their harmful drug use, reduce drug use related risks such as sepsis and overdose and stay alive for longer. However a public health perspective in relation to problem drug use isn't always either apparent or readily understood and to that end there is still a significant need to continue the arguments and debate that treatment and interventions for problem and dependent drug users need to extend beyond an individualistic approach. For the purposes of discussion in this article public and population health will be used interchangeably.

Summary

A recognition and acceptance that a public and population health approach to the management of problem drug users is sound public health policy also then requires a long term commitment in terms of staffing and resources where service delivery mirrors that of chronic condition management.

Randomized controlled trial comparing the effectiveness and safety of intranasal and intramuscular naloxone for the treatment of suspected heroin overdose

AIMS

Traditionally, the opiate antagonist naloxone has been administered parenterally; however, intranasal (i.n.) administration has the potential to reduce the risk of needlestick injury. This is important when working with populations known to have a high prevalence of blood-borne viruses. Preliminary research suggests that i.n. administration might be effective, but suboptimal naloxone solutions were used. This study compared the effectiveness of concentrated (2 mg/ml) i.n. naloxone to intramuscular (i.m.) naloxone for suspected opiate overdose.

METHODS

This randomized controlled trial included patients treated for suspected opiate overdose in the pre-hospital setting. Patients received 2 mg of either i.n. or i.m. naloxone. The primary outcome was the proportion of patients who responded within 10 minutes of naloxone treatment. Secondary outcomes included time to adequate response and requirement for supplementary naloxone. Data were analysed using multivariate statistical techniques.

RESULTS

A total of 172 patients were enrolled into the study. Median age was 29 years and 74% were male. Rates of response within 10 minutes were similar: i.n. naloxone (60/83, 72.3%) compared with i.m. naloxone (69/89, 77.5%) [difference: -5.2%, 95% confidence interval (CI) -18.2 to 7.7]. No difference was observed in mean response time (i.n.: 8.0, i.m.: 7.9 minutes; difference 0.1, 95% CI -1.3 to 1.5). Supplementary naloxone was administered to fewer patients who received i.m. naloxone (i.n.: 18.1%; i.m.: 4.5%) (difference: 13.6%, 95% CI 4.2-22.9).

CONCLUSIONS

Concentrated intranasal naloxone reversed heroin overdose successfully in 82% of patients. Time to adequate response was the same for both routes, suggesting that the i.n. route of administration is of similar effectiveness to the i.m. route as a first-line treatment for heroin overdose.

Factors associated with mortality in Scottish patients receiving methadone in primary care: retrospective cohort study

OBJECTIVE

To assess predictors of mortality in a population of people prescribed methadone.

DESIGN

Retrospective cohort study.

SETTING

Geographically defined population in Tayside, Scotland.

PARTICIPANTS

2378 people prescribed and dispensed liquid methadone between January 1993 and February 2004.

MAIN OUTCOME MEASURES

All cause mortality (primary outcome) and drug dependent cause specific mortality (secondary outcome) by means of Cox proportional hazards models during 12 years of follow-up.

RESULTS

Overall, 181 (8%) people died. Overuse of methadone (adjusted hazard ratio 1.67, 95% confidence interval 1.05 to 2.67), history of psychiatric admission (2.47, 1.67 to 3.66), and increasing comorbidity measured as Charlson index >or=3 (1.20, 1.15 to 1.26) were all associated with an increase in all cause mortality. Longer duration of use (adjusted hazard ratio 0.95, 0.94 to 0.96), history of having urine tested (0.33, 0.22 to 0.49), and increasing time since last filled prescription were protective in relation to all cause mortality. Drug dependence was identified as the principal cause of death in 60 (33%) people. History of psychiatric admission was significantly associated with drug dependent death (adjusted hazard ratio 2.41, 1.25 to 4.64), as was history of prescription of benzodiazepines (4.35, 1.32 to 14.30).

CONCLUSIONS

Important elements of care in provision of methadone maintenance treatment are likely to influence, or be a marker for, a person's risk of death.

Overdose training and take-home naloxone for opiate users: prospective cohort study of impact on knowledge and attitudes and subsequent management of overdoses

AIM

To examine the impact of training in overdose management and naloxone provision on the knowledge and confidence of current opiate users; and to record subsequent management of overdoses that occur during a 3-month follow-up period.

DESIGN

Repeated-measures design to examine changes in knowledge and confidence immediately after overdose management training; retention of knowledge and confidence at 3 months; and prospective cohort study design to document actual interventions applied at post-training overdose situations.

METHOD

A total of 239 opiate users in treatment completed a pre-training questionnaire on overdose management and naloxone administration and were re-assessed immediately post-training, at which point they were provided with the take-home emergency supply of naloxone. Three months later they were re-interviewed.

RESULTS

Significant improvements were seen in knowledge of risks of overdose, characteristics of overdose and appropriate actions to be taken; and in confidence in the administration of naloxone. A 78% follow-up rate was achieved (186 of 239) among whom knowledge of both the risks and physical/behavioural characteristics of overdose and also of recommended management actions was well retained. Eighteen overdoses (either experienced or witnessed) had occurred during the 3 months between the training and the follow-up. Naloxone was used on 12 occasions (a trained client's own supply on 10 occasions). One death occurred in one of the six overdoses where naloxone was not used. Where naloxone was used, all 12 resulted in successful reversal.

CONCLUSIONS

With overdose management training, opiate users can be trained to execute appropriate actions to assist the successful reversal of potentially fatal overdose. Wider provision may reduce drug-related deaths further. Future studies should examine whether public policy of wider overdose management training and naloxone provision could reduce the extent of opiate overdose fatalities, particularly at times of recognized increased risk.

Estimating heroin epidemics with data of patients in methadone maintenance treatment, collected during a single treatment day

AIMS

Effects of differing drug policies are difficult to evaluate, because time trends in the spread of heroin use, the most problematic illicit drug world-wide, are unknown in almost all countries. We aimed to develop a simple method to estimate these dynamics with data that can be gathered from patients in substitution treatment within a single day.

DESIGN

We tested the assumption that being in substitution treatment on any day depends solely upon individual time since onset of regular heroin use (following a 'general inclusion function'). We used data from the case register for substitution treatments in the canton of Zurich (1992--2004), comprising 9518 patients, to model a 'general inclusion function'. Applying this function, we calculated 30 incidence curves for heroin dependence, each with data of one of 30 randomly chosen treatment days between 1992 and 2004.

FINDINGS

Incidence modelling led to 30 similar curves, and therefore our hypothesis was corroborated. Additionally, our approach also revealed a restricted access to substitution treatment in the early 1990s and a decline in demand due to the introduction of heroin-assisted treatment from 1994 onwards.

CONCLUSIONS

In the canton of Zurich, the probability of being in substitution treatment can be described by a 'general inclusion function', and therefore dynamics of heroin epidemics can be estimated based on data of a single treatment day. Adaptation of our function to areas with a more restricted access to substitution treatment may permit these estimations also in other regions or countries. Thus, our approach facilitates the urgently needed assessment of the effects of different drug policies.

Risk of fatal overdose during and after specialist drug treatment: the VEdeTTE study, a national multi-site prospective cohort study

BACKGROUND

Specialist drug treatment is critical to overdose prevention; methadone maintenance is effective, but we lack evidence for other modalities. We evaluate the impact of a range of treatments for opiate dependence on overdose mortality.

METHODS

Prospective cohort study of 10,454 heroin users entering treatment 1998-2001 in Italy followed-up for 10,208 person-years in treatment and 2,914 person-years out of treatment. Standardized overall mortality ratios (SMR) estimate excess mortality risk for heroin users in and out of treatment compared to the general population. Cox models compare the hazard ratio (HR) of overdose between heroin users in treatment and out of treatment.

RESULTS

There were 41 overdose deaths, 10 during treatment and 31 out of treatment, generating annual mortality rates of 0.1% and 1.1% and SMRs of 3.9 [95% confidence interval (CI) 2.8-5.4] and 21.4 (16.7-27.4), respectively. Retention in any treatment was protective against overdose mortality (HR 0.09 95% CI 0.04-0.19) compared to the risk of mortality out of treatment, independent of treatment type and potential confounders. The risk of a fatal overdose was 2.3% in the month immediately after treatment and 0.77% in the subsequent period; compared to the risk of overdose during treatment the HR was 26.6 (95% CI 11.6-61.1) in the month immediately following treatment and 7.3 (3.3-16.2) in the subsequent period.

CONCLUSIONS

We demonstrate that a range of treatments for heroin dependence reduces overdose mortality risk. However, the considerable excess mortality risk in the month following treatment indicates the need for greater health education of drug users and implementation of relapse and overdose death prevention programmes. Further investigation is needed to measure and weigh the potential benefits and harms of short-term therapies for opiate use.

Acute opiate overdose in Tehran: the forgotten role of opium

INTRODUCTION

The global epidemic of opiate use continues to spread and is an increasing burden especially in developing countries. Acute opiate overdose (AOO) is one of the most dramatic complications of drug abuse. The purpose of this study is to examine the epidemiology of acute opiate overdose in a poisoning center in Tehran.

METHODS

In this cross-sectional survey, patients who attended the emergency room of Loghman-Hakim hospital - the only poisoning center in Tehran - and diagnosed with acute opiate overdose over a six month period were included.

RESULTS

Overdose was more common among men (91.2%). The mean and standard deviation of age was 36.9+/-15. The most frequent opiate agent was opium (56.5%) followed by heroin. Opium was most commonly used by regular users, as a single agent and through ingestion. Benzodiazepines, antidepressants and alcohol were the most common agents consumed accompanied with opiates. The mortality rate was 8.8% which was not significantly different between cases of heroin and opium overdose.

CONCLUSION

Opium was the major cause of overdose in our study. This result suggests that opium is not a harmless form of addiction although it is regarded as a thing of the past in many countries.

The association between change in social network characteristics and non-fatal overdose: results from the SHIELD study in Baltimore, MD, USA

BACKGROUND

Social network factors have been reported to be associated with non-fatal overdose. Yet, few studies have examined how changes in social network characteristics may influence overdose risk. The purpose of this study was to examine the relationship between changes in social network and non-fatal overdose.

METHODS

Data for this study came from 659 participants enrolled in the Self-Help in Eliminating Life-Threatening Diseases (SHIELD) study, who reported details about their non-fatal overdose experience between enrollment and a follow-up visit. Social network characteristics were described at both time points and net change in network composition was calculated.

RESULTS

The sample was predominately male (56%), African-American (96%) and unemployed (78%). Experience of non-fatal overdose between time points was reported by 15%. Older age was associated with non-fatal overdose. Interaction between incarceration status and drug use was statistically significant. Protective factors were having a denser network at baseline and a network that became denser after adjusting for gender, homelessness, incarceration, drug use and total network size.

CONCLUSIONS

Drug users' social networks are an important target for overdose prevention interventions. Further research on overdose risk and movement of specific network members in and out of networks is warranted.

London audit of drug-related overdose deaths: characteristics and typology, and implications for prevention and monitoring

OBJECTIVES

To describe the circumstances and draft a typology of drug-related overdose deaths.

SETTING

London, 2003.

METHODS

An audit of 148 drug overdose deaths (involving heroin, methadone, dihydrocodeine, cocaine, amphetamine or MDMA) investigated by coroners during 2003. Information extracted on toxicology, pathology and circumstances were used to identify drug(s) implicated in the death.

RESULTS

Poly- or multiple drug use was detected in the majority of deaths with at least 69 different combinations, including 66% for heroin and 42% for cocaine. Six categories of death were identified involving an opiate (100, 68%); cocaine (14, 9%); other controlled drug (five, 3%); mixed drug overdose (18, 12%); other prescribed drug (five, 3%); and other causes (seven, 5%). A witness was present and the death was not instantaneous in 92 (61%) cases, although evidence in the coronial file suggested that in the majority of cases the overdose went unnoticed until too late to intervene. In all, 15 (one in 10) of the deceased were released from prison within 3 months of death; and 37 (one in four) were reported as in receipt of a methadone prescription.

CONCLUSIONS

Perhaps for the first time in the United Kingdom cocaine was detected in more drug overdose deaths than methadone. However, reducing heroin use is central to the prevention of drug-related deaths. We recommend that overdose prevention encompasses strategies to encourage a 'mutual duty of care' among problem drug users, and in the United Kingdom further investigation of the relationship of methadone treatment failures on overall trends in drug-related deaths is merited.

Changes to the daily pattern of methadone-related deaths in England and Wales, 1993–2003

Previous studies suggest that fatal poisoning deaths involving methadone occur more frequently on the weekends. We assessed changes in the daily pattern of mortality because of methadone poisoning following a review of drug misuse services in 1996 and publication of revised clinical guidelines in 1999. We also compared this to the daily pattern of deaths involving heroin/morphine. The Office for National Statistics provided data on all deaths in England and Wales between 1993 and 2003 for which methadone and heroin/morphine were mentioned on the coroner's certificate of death registration after inquest, with or without alcohol or other drugs. There were 3098 deaths involving methadone. The death rate increased up to 1997 and then declined. Initially, there was a marked excess of deaths occurring on Saturdays. The rate of decline was greatest for deaths occurring on Saturdays. As a result, the Saturday peak disappeared (P = 0.006). There were 6328 deaths involving heroin/morphine. No change in the daily pattern of heroin/morphine deaths was observed during the study period. Although the marked change in the epidemiology of methadone deaths coincided with recommendations for service redevelopment and clinical management of methadone treatment, the contribution of improved prescribing practice or treatment services is unclear.

Systemic disease among cases of fatal opioid toxicity

AIMS

To determine levels of systemic disease among cases of death due to opioid toxicity.

DESIGN

Analysis of coronial cases.

SETTING

Sydney, Australia.

CASES

A total of 841 cases of death due to opioid toxicity (1 January 1998-31 December 2002).

FINDINGS

Ventricular hypertrophy was present in 5.9% of cases and severe coronary artery atherosclerosis in 5.7%. Severe coronary pathology was more pronounced among older cases. Pre-existing bronchopneumonia was present in 13.2% of cases. Hepatic pathology was the most common type of pathology, and was far more marked among older cases. Cirrhosis was present in 25.3% of those aged > 44 years. Levels of renal pathology were comparatively low, but were related significantly to increasing age. Systemic disease in more than one organ system was present in 24.4% of cases, and was related to increasing age (44% of those aged > 44 years). The only pathology for which gender was an independent predictor among opioid cases was ventricular hypertrophy, more common in males.

CONCLUSIONS

Systemic disease, most prominently liver disease, is common among fatal opioid toxicity cases, and may be a factor in understanding the dynamics and age demographics of opioid-related death.

Variations in respiratory distress characterize the acute agonal period during heroin overdose death: Relevance to postmortem mRNA studies

AIMS

To determine whether there are factors during apparent rapid heroin overdose death that affect agonal state and thus brain pH (index of hypoxia) that can influence neurobiological systems linked to drug abuse.

DESIGN AND METHODS

Brain specimens and autopsy/medical reports were investigated in subjects dying from heroin overdose (n=70) and compared to normal controls (n=45) as well as suicide victims (n=31) with a documented rapid cause of death. Detailed autopsy material was characterized as to positive and negative respiratory distress in relation to brain pH; drug toxicity and other demographic information was also evaluated. In situ hybridization histochemistry was used to study mRNA expression levels of dopamine (e.g., D2 receptor, dopamine transporter) and opioid (e.g., proenkephalin) related markers in various structures in relation to brain pH.

FINDINGS

Brain pH was generally reduced in heroin overdose cases versus normal and suicide subjects. There was, however, significant variation in heroin overdose deaths related to differences in respiratory distress that differentially altered brain pH levels. Various factors such as vomit inhalation, resuscitation, pulmonary embolism and suffocation contributed to positive respiratory distress. Elevated brain pH was observed in heroin overdose with positive alcohol toxicity suggesting potentiated alcohol-induced rapidity of heroin deaths. mRNA expression levels of the dopamine-related genes and proenkephalin were positively correlated with brain pH.

CONCLUSIONS

Respiratory distress contributes to variations in the acute agonal state during heroin overdose death that differentially alters brain pH levels and significantly impacts mRNA levels. Such findings should be considered for postmortem molecular/neurochemical neurobiological studies of opiate abusers.

Recent trends in narcotic deaths

The prevalence of overdose deaths from opioids is still generally increasing throughout the world. Heroin is still the predominant illicit opioid of interest to toxicology laboratories because of its continuing widespread availability and its ability to elicit respiratory depression and coma. In many countries methadone continues to play a major role in cases of drug toxicity because of its large-scale use to treat opioid dependency and its high potency and long duration of action. Increasingly, buprenorphine is being used as an alternative pharmacotherapy, and although apparently safer than methadone, it still has an inherent risk of toxicity when used with CNS depressants such as benzodiazepines or when injected. Morphine continues to be the dominant analgesic; however, oxycodone, hydromorphone, hydrocodone, and fentanyl are increasingly being used and will require increasing efforts by toxicology laboratories to ensure that these substances are adequately covered by testing programs.

Unintentional prescription drug overdose deaths in New Mexico, 1994-2003

BACKGROUND

New Mexico has the highest rate of drug-induced mortality in the United States. The contribution of prescription drugs to the total overdose death rate has not been adequately described.

METHODS

A total of 1,906 unintentional drug overdose deaths occurring in 1994 to 2003 in New Mexico were analyzed. Unintentional drug overdose death was defined as death caused by prescription, illicit, or a combination of drugs, as determined by a pathologist. Deaths were investigated annually by the medical examiner and data were analyzed in 2004-2005. Rates and trends of total and prescription drug overdose death were calculated, decedent characteristics were analyzed, and common drug combinations causing death were described.

RESULTS

The rate of unintentional prescription drug overdose death increased by 179% (1.9 to 5.3/100,000) from 1994 to 2003. A high percentage of prescription drug overdose decedents were white non-Hispanic (63.2%) and female (43.9%). These decedents were older and less frequently had alcohol listed as an additional cause of death than decedents of other drug overdose categories. Of all deaths caused by prescription drug(s) (n =765), 590 (77.1%) were caused by opioid painkillers, 263 (34.4%) by tranquilizers, and 196 (25.6%) by antidepressants.

CONCLUSIONS

The rate of prescription drug overdose death in New Mexico increased significantly over the 10-year study period. Comprehensive surveillance of drug overdose deaths is recommended to describe their occurrence in the context of both medical and diverted use of prescription drugs. Understanding decedent profiles and the potential risk factors for prescription drug overdose death is crucial for effective drug overdose prevention education among healthcare providers.

Do young heroin users in Madrid, Barcelona and Seville have sufficient knowledge of the risk factors for unintentional opioid overdose?

To identify the self-perceived reasons for unintentional opioid overdose of young heroin users in three Spanish cities and their agreement with objective risk factors for overdose. Computer-Assisted Personal Interviews (CAPI) were held with 991 street-recruited current heroin users aged 18-30. The general reasons for overdose and the reasons for the last overdose suffered were explored with open-ended (OEQs) and pre-coded questions (PCQs). Limited knowledge of overdose risk factors was defined as mention of fewer than two objective risk factors for unintentional overdose in the OEQ. Univariate, bivariate, and logistic regression methods were used. 77.8% (Seville), 64.9% (Madrid) and 57.2% (Barcelona) of participants have limited knowledge of overdose risk factors. Residence in Seville and not having attended courses or meetings on overdoses were significantly associated with limited knowledge, after adjusting for other factors. The most frequently identified general reasons in OEQ or PCQ were using heroin in large amounts (66.8%), together with tranquilizers (62.0%), adulterated (60.7%), or purer than usual (57.6%). Most reasons were selected more frequently in PCQ than in OEQ, especially rapid injection of the entire dose and using heroin shortly after using tranquilizers or alcohol, by injection, or after a period of abstinence. The results were similar for overdoses suffered by participants. Most young heroin users do not have sufficient knowledge of overdose risk factors, especially the use of heroin by injection, after a period of abstinence, or together with alcohol or methadone. Specific informational or educational programs adapted to the local context are critically needed.

Nonketotic hyperglycemic coma in toddlers after unintentional methadone ingestion

Methadone overdoses are increasing in parallel with the increased frequency of opiate substitution therapy in adults. Although unintentional methadone intoxication in children is rare, it is becoming more frequently recognized. We report 3 cases of unintentional methadone overdose in toddlers who initially displayed central nervous system depression associated with severe nonketotic hyperglycemia and discuss the possible pathophysiologic mechanisms of an underrecognized symptom of opiate intoxication in young children.

QT prolongation and torsades de pointes among methadone users: reports to the FDA spontaneous reporting system

BACKGROUND

Recent case series have associated the synthetic opioid, methadone, with QT prolongation and torsades de pointes (TdP) ventricular arrhythmia.

STUDY OBJECTIVE

To review and analyze adverse events (QT prolongation and TdP) reported to the Food and Drug Administration (FDA) to determine the patient characteristics, dosages of methadone, and outcomes of methadone-treated patients.

METHODS

The study design was a retrieval and retrospective analysis of reports of adverse events associated with methadone voluntarily reported to the FDA MedWatch program from 1969 to October 2002. Reports were accessed via QSCAN (DrugLogic, Reston, VA), a commercially available software interface.

RESULTS

In a total of 5,503 reports of adverse events associated with methadone, 43 (0.78%) noted the occurrence of TdP and 16 (0.29%) QT prolongation. Doses were reported in 42/59 (71%) of cases; mean dose was 410 +/- 349 mg/day (median 345, range 29-1680). The dosages for 10 of the 42 cases (29%) were within the recommended range for methadone maintenance treatment, 60-100 mg/day. Female gender, interacting medications, hypokalemia, hypomagnesemia, and structural heart disease, risk factors previously identified with other drugs known to cause TdP, were found in 44 (75%) cases. Most adverse events required hospitalization or resulted in prolonged hospitalization (28/59, 47%) and 5/59 (8%) were fatal.

CONCLUSIONS

Cases of TdP associated with methadone have been reported to the FDA MedWatch system. Analysis of the cases provides evidence that prolonged QT and TdP can occur over a wide range of dosages including those usually recommended for addiction treatment.

Evaluating the impact of methadone maintenance programmes on mortality due to overdose and aids in a cohort of heroin users in Spain

AIMS

To assess the relationship between methadone treatment (MT) and overdose and HIV/AIDS mortality among heroin users resident in Barcelona city.

DESIGN

All patients who started treatment in any treatment centre between 1992 and 1997 were included in a cohort the first time they were admitted for heroin addiction treatment. Follow-up controls were carried out every 9 months, on average, until 31 December 1999. Variables, both constant and varying over time, were fitted into Cox regression models.

FINDINGS

The study recruited 5049 patients, which provided 23,048.2 person-years. Fifty per cent were in MT during the study period; of the total cohort 1005 patients died: 38.4% due to AIDS, 34.7% to overdose and 27% to other causes. Overall mortality decreased from 5.9 deaths per 100 person-years in 1992 to 1.6 in 1999. Globally, life expectancy at birth was 39 years, 38 years lower than that of the general population. The main factor for overdose mortality was not being in MT at the time of death [relative ratio (RR) = 7.1]; other factors were being a current injector at baseline and being HIV positive. For AIDS mortality, the main factor was the calendar year (RR for 1996 versus 1999 = 4.6), the next major factor was more than 10 years of heroin consumption, followed by not being in MT, being unemployed, then having a prison record.

CONCLUSIONS

The observed mortality decline could be linked to the effectiveness of low-threshold MT. The life expectancy of heroin users increased by 21 years during the study period.

The effect of HIV infection on overdose mortality

OBJECTIVES

To quantify the association of HIV infection with overdose mortality and explore the potential mechanisms.

DESIGN

A prospective cohort study.

METHODS

A total of 1927 actively injecting drug users who were HIV seronegative at baseline, of whom 308 later HIV seroconverted, were followed semi-annually for death from 1988 to 2001. Survival analyses using marginal structural and standard Cox models were used to evaluate the effect of HIV infection on the risk of overdose mortality.

RESULTS

Overdose death rates were higher in HIV-seropositive than HIV-seronegative drug users: 13.9 and 5.6 per 1000 person-years, respectively (P < 0.01). The hazard ratio (HR) was 2.54 [95% confidence interval (CI) 1.47, 4.38] for the marginal structural model and 2.06 (95% CI 1.25, 3.38) for the standard Cox model, both adjusted for demographics, drug injection characteristics, alcohol abuse, substance abuse treatment, and sexual orientation. Adjusting for possible time-varying mediators (i.e. drug use, medical conditions and healthcare access) in extended marginal structural models reduced the effect of HIV on overdose mortality by 30% (HR 1.82, 95% CI 1.01, 3.30). Abnormal liver function was associated with a higher risk of overdose mortality (HR 2.00, 95% CI 1.05, 3.84); adjustment for this further reduced the effect of HIV on overdose mortality.

CONCLUSION

HIV infection was associated with a higher risk of overdose mortality. Drug use behavior, systematic disease and liver damage associated with HIV infection appeared to account for a substantial portion of this association. The data suggest a group to target with interventions to reduce overdose mortality rates.

The urban built environment and overdose mortality in New York City neighborhoods

Accidental drug overdose continues to be a substantial cause of mortality for drug users. Characteristics of the neighborhood built environment may be important determinants of the likelihood of drug overdose mortality independent of individual-level factors. Using data from the New York City Office of the Chief Medical Examiner, we conducted a multilevel case control study using data on accidental overdose deaths as cases and non-overdose accidental deaths as controls. We used archival data from the New York City Housing and Vacancy Survey and the Mayor's Office of Operations to assess characteristics of neighborhood external (e.g. dilapidation of buildings) and internal (e.g. quality of utilities in houses) built environment. Multilevel analyses were used to assess the relations between the neighborhood built environment and the likelihood of overdose death. Six out of the eight characteristics of the external environment studied and three out of the six characteristics of the internal environment studied were significantly associated with the likelihood of fatal drug overdose in multilevel models after adjusting for individual-level (age, race, sex) and neighborhood-level (income, drug use) variables. Deterioration of the built environment, particularly the external environment, is associated with an increased likelihood of fatal accidental drug overdose. Disinvestment in social resources, psychosocial stressors, neighborhood differences in response to a witnessed overdose, and differences in vulnerability to the adverse consequences of drug use in different neighborhoods may explain the observed associations.

Unintentional methadone-related overdose death in New Mexico (USA) and implications for surveillance, 1998-2002

AIMS

To determine death rates from methadone over time, to characterize methadone-related death and to discuss public health surveillance of methadone-related death.

DESIGN

We analyzed medical examiner data for all unintentional drug overdose deaths in New Mexico, USA, between 1998 and 2002.

MEASUREMENTS

Age-adjusted death rates for methadone-related death, logistic regression models for likelihood of methadone-related death among all unintentional drug overdose deaths and bivariate comparisons within methadone-related death.

FINDINGS

Of 1120 drug overdose deaths during this period, there were 143 (12.8%) methadone-related deaths; the death rate decreased over the time period, averaging 1.6 per 100,000. Of 143 methadone-related deaths, 22.4% were due to methadone alone, 23.8% were due to methadone/prescription drugs (no illicit drugs), 50.3% were due to methadone/illicit drugs and 3.5% were due to methadone/alcohol. These groups were significantly different in demographics, health history and circumstances of death. Of 79 decedents (55.2%) with a known source of methadone, 68 obtained methadone through a physician prescription (31 for methadone maintenance treatment (MMT), 27 for managing pain and 10 had unknown reason for prescription).

CONCLUSIONS

Methadone-related death rates and the proportion of methadone-related death among all drug overdose deaths decreased in New Mexico from 1998 to 2002. It is important for surveillance of methadone-related death to assess multiple drug causes, not just underlying cause. Also, methadone for pain management must be examined alongside MMT and when possible, methadone co-intoxication should be described in the context of other drugs causing death.

Endogenous opiates and behavior: 2003

This paper is the 26th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over a quarter-century of research. It summarizes papers published during 2003 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).

Determinants of overdose incidents among illicit opioid users in 5 Canadian cities

BACKGROUND

Drug overdose is a major cause of death and illness among illicit drug users. Previous research has indicated that most illicit drug users experience nonfatal overdoses and has suggested a variety of factors that are associated with risk of overdose. In this study, we examined the occurrence of and the factors associated with nonfatal overdoses within a Canadian sample of illicit opioid users not enrolled in treatment at the time of study recruitment.

METHODS

Interviewers used a standard questionnaire to collect data on sociodemographic characteristics, drug use, health and health care, experience in the criminal justice system and treatment for drug problems; they also performed standard assessments for mental health and infectious disease. The association between overdose and sociodemographic and drug-use factors was examined with chi(2) and t test analyses; marginally significant variables were examined with logistic regression to determine independent effects.

RESULTS

A total of 679 subjects were interviewed; 651 provided answers sufficient for this analysis. One hundred and twelve (17.2%) of the 651 respondents reported an overdose episode in the previous 6 months. In the logistic regression analysis (after adjustment for sociodemographic factors), homelessness, noninjection use of hydromorphone in the past 30 days and involvement in drug treatment in the past 12 months were predictors of overdose (p < 0.05).

INTERPRETATION

Overdose poses a considerable health risk for illicit opioid users. We found that a diverse set of factors was associated with overdose episodes. Prevention efforts will likely be more effective if they can be directed to specific causal factors.

Overdose deaths attributed to methadone and heroin in New York City, 1990-1998

AIMS

Methadone treatment has been shown to be an effective intervention that can lower the risk of heroin-induced overdose death. Recent reports have suggested increases in methadone-induced overdose deaths in several locations in the USA and in Europe. This study investigated the role of methadone and opiates in accidental overdose deaths in New York City.

DESIGN

We analysed data from the Office of the Chief Medical Examiner to examine all accidental drug overdose deaths in New York City between 1990 and 1998.

FINDINGS

Of 7451 total overdose deaths during this period, there were 1024 methadone-induced overdose deaths, 4627 heroin-induced overdose deaths and 408 overdose deaths attributed to both methadone and heroin. Fewer than a third as many accidental overdose deaths were attributed to methadone than were attributed to heroin during this period. The proportion of accidental overdose deaths attributed to methadone did not change appreciably (12.6-15.8% of total overdose mortality), while the proportion of overdose deaths attributed to heroin increased significantly (53.5-64.2%) during the period of study.

CONCLUSIONS

There was no appreciable increase in methadone-induced overdose mortality in New York City during the 1990s. Both heroin-induced overdose mortality and prescriptions of methadone increased during the same interval.

Drug-related mortality and fatal overdose risk: pilot cohort study of heroin users recruited from specialist drug treatment sites in London

Fatal overdose and drug-related mortality are key harms associated with heroin use, especially injecting drug use (IDU), and are a significant contribution to premature mortality among young adults. Routine mortality statistics tend to underreport the number of overdose deaths and do not reflect the wider causes of death associated with heroin use. Cohort studies could provide evidence for interpreting trends in routine mortality statistics and monitoring the effectiveness of strategies that aim to reduce drug-related deaths. We aimed to conduct a retrospective mortality cohort study of heroin users recruited from an anonymous reporting system from specialist drug clinics. Our focus was to test whether (1). specialist agencies would agree to participate with a mortality cohort study, (2). a sample could be recruited to achieve credible estimates of the mortality rate, and (3). ethical considerations could be met. In total, 881 heroin users were recruited from 15 specialist drug agencies. The overall mortality rate of the cohort of heroin users was 1.6 (95% confidence interval [CI], 1.1 to 2.2) per 100 person-years. Mortality was higher among males, heroin users older than 30 years, and injectors, but not significantly higher after adjustment in a Cox proportional hazard model. Among the 33 deaths, 17 (52%) were certified from a heroin/methadone or opiate overdose, 4 (12%) from drug misuse, 4 (12%) unascertained, and 8 (24%) unrelated to acute toxic effects of drug use. Overall, the overdose mortality rate was estimated to be at least 1.0 per 100 person-years. The standardized mortality ratio (SMR) was 17 times higher for female and male heroin users in the cohort compared to mortality in the non-heroin-using London population aged 15-59 years. The pilot study showed that these studies are feasible and ethical, and that specialist drug agencies could have a vital role to play in the monitoring of drug-related mortality.