A comparison of blood toxicology of heroin-related deaths and current heroin users in Sydney, Australia

A hierarchical 3D camellia-like molybdenum tungsten disulfide architectures for the determination of morphine and tramadol

A practical technique was applied to fabricate MoWS₂ nanocomposite through a one-pot hydrothermal method for use as the electrocatalyst. The characterization of MoWS₂ nanocomposite was investigated by several techniques to identify the size, crystal structure, and elemental composition. MoWS₂ nanocomposite exhibited a unique and well-defined hierarchical structure with neatly and densely piled nanopetals acting as the active sites in the electrocatalytic reactions. A carbon screen-printed electrode (CSPE) modified with interesting MoWS₂ nanopetals (MoWS₂/CSPE) was constructed. Subsequently, the electrochemical oxidation of morphine on fabricated MoWS₂/CSPE was studied. Experimental results confirm that under optimized conditions, the maximum oxidation current of morphine occurs at 275 mV in the case of MoWS₂/CSPE that is around 100 mV more negative than that observed in the case of the unmodified CSPE and about 2.6 times increase was observed for the oxidation peak current. The analytical approach was obtained by differential pulse voltammetry in accordance with the relationship between the oxidation peak current and the morphine concentration. The oxidation peak currents for morphine were found to vary linearly with its concentrations in the range of 4.8 × 10^-8-5.05 × 10^-4 M with the detection limit of 1.44 × 10^-8 M. Two completely separated signals occured at the potentials of 275 mV and 920 mV for oxidation of morphine and tramadol at the surface of MoWS₂/CSPE which are sufficient for determination of morphine in the presence of tramadol. The presence of morphine was also detected in real samples using the introduced approach. Graphical abstract Schematic representation of fabrication of the MoWS₂ nanocomposite through a one-pot hydrothermal method for use as the electrocatalyst. A carbon screen-printed electrode was modified with MoWS₂ nanocomposite. Subsequently, the electrochemical oxidation of morphine on the fabricated electrode was studied.

Not just heroin: Extensive polysubstance use among US high school seniors who currently use heroin

BACKGROUND

Heroin-related deaths are on the rise in the US and a large portion of heroin overdoses involve co-use of other drugs such as benzodiazepines. A better understanding of heroin polysubstance use patterns could help discern better prevention measures.

METHODS

Data were examined from past-month ("current") heroin users from a nationally representative sample of high school seniors in the Monitoring the Future study (2010-2016, n = 327). We examined how past-month use and frequency of use of various drugs relate to frequency of current heroin use using chi-square and multivariable ordinal logistic regression.

RESULTS

Prevalence of any past-month use of various other drugs (and past-month use 10+ times) tends to increase as the frequency of heroin use increases; however, other drug use tends to decline among those reporting the use of heroin 40+ times in the past month. In multivariable models controlling for demographic characteristics, most levels of alcohol use were associated with decreased odds of higher-frequency heroin use (ps<.05). Nonmedical opioid (aOR = 5.84, p = .037) and tranquilizer (aOR = 14.63, p = .045) use 40+ times in the past month were associated with increased odds of higher-frequency heroin use.

CONCLUSIONS

High school seniors who use heroin also use multiple other drugs. Increases in the frequency of heroin use are associated with shifts in the nature and frequency of polysubstance use, with a higher frequency of heroin use associated with the highest percentage and frequency of use of depressants (nonmedical opioid and benzodiazepine use), compounding the risk of overdose. Prevention measures should consider polysubstance use patterns among heroin-using adolescents.

Worldwide Prevalence and Trends in Unintentional Drug Overdose: A Systematic Review of the Literature

BACKGROUND

Drug overdose is an important, yet an inadequately understood, public health problem. Global attention to unintentional drug overdose has been limited by comparison with the scope of the problem. There has been a substantial increase in drug overdose incidence and prevalence in several countries worldwide over the past decade, contributing to both increased costs and mortality.

OBJECTIVES

The aim of this study was to systematically synthesize the peer-reviewed literature to document the global epidemiological profile of unintentional drug overdoses and the prevalence, time trends, mortality rates, and correlates of drug overdoses. We searched different combinations of Medical Subject Headings (MeSH) terms in PubMed for articles published from 1980 until July 2013, and we organized these results in tabular spreadsheets and compared them. We restricted the search to English-language articles that deal with unintentional overdose, focusing on 1 or more of the following key constructs: prevalence, time trends, mortality rates, and correlates. The term "overdose" as a MeSH major topic yielded 1076 publications. In addition, we searched the following combinations of nonmajor MeSH terms: "street drugs" and "overdose" yielded 180, "death" and "overdose" yielded 114, and "poisoning" and "drug users" yielded 17. There was some overlap among the searches. Based on the search and inclusion and exclusion criteria, we selected a total of 169 relevant articles for this article based on a close review of abstracts.

RESULTS

We found wide variability in lifetime prevalence of experiencing a nonfatal overdose or witnessing an overdose, and in mortality rates attributable to overdose. Lifetime prevalence of witnessed overdose among drug users (n = 17 samples) ranged from 50% to 96%, with a mean of 73.3%, a median of 70%, and a standard deviation of 14.1%. Lifetime prevalence of drug users personally experiencing a nonfatal overdose (n = 27 samples), ranged from 16.6% to 68.0% with a mean of 45.4%, a median of 47%, and a standard deviation of 14.4%. Population-based crude overdose mortality rates (n = 28 samples) ranged from 0.04 to 46.6 per 100 000 person-years. This range is likely attributable to the diversity in regions, time periods, and samples. Most studies on longitudinal trends of overdose death rates or overdose-related hospitalization rates showed increases in overdose death rates and in overdose-related hospitalization rates across time, which have led to peaks in these rates at the present time. An overall trend of increasing deaths from prescription opioid use and decreasing deaths from illicit drug use in the past several years has been noted across most of the literature. With the increase in prescription opioid overdose deaths, drug overdose is not just an urban problem: rural areas have seen an important increase in overdose deaths. Lastly, cocaine, prescription opioids, and heroin are the drugs most commonly associated with unintentional drug overdoses worldwide and the demographic and psychiatric correlates associated with unintentional drug overdoses are similar globally.

CONCLUSIONS

There is a need to invest in research to understand the distinct determinants of prescription drug overdose worldwide. Several other countries need to collect in a systematic and continuous fashion such data on sales of prescription opioids and other prescription drugs, nonmedical use of prescription drugs, and hospitalization secondary to overdoses on prescription drugs. The sparse evidence on the environmental determinants of overdose suggests a need for research that will inform the types of environmental interventions we can use to prevent drug overdose. Methodological issues for future studies include enhancing data collection methods on unintentional fatal and nonfatal overdoses, and collecting more detailed information on drug use history, source of drug use (for prescription drugs), and demographic and psychiatric history characteristics of the individual who overdosed.

Serum and urine concentrations of morphine and morphine metabolites in patients with advanced cancer receiving continuous intravenous morphine: an observational study

BACKGROUND

The feasibility and clinical implication of drug monitoring of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) need further investigation. This study aimed to determine what predicts serum concentrations of morphine in cancer patients receiving continuously intravenous morphine, the relationships between serum concentration of morphine/its metabolites and urinary concentrations, and the relation between morphine concentrations and with clinical outcomes.

METHODS

We collected serum and urine samples from 24 patients with advanced cancer undergoing continuously intravenous morphine therapy. Serum samples were obtained at day one. Spot urine samples were collected once daily on three consecutive days. Pain and adverse drug events were assessed using the Korean version of MD Anderson Symptom Inventory.

RESULTS

A total of 96 samples (72 urine and 24 serum samples) were collected. Median dose of morphine was 82.0 mg/24 h. In a multivariate analysis, total daily morphine dose was the most significant predictors of both serum and urine concentration of morphine. Morphine, M6G, and M3G in serum and urine were statistical significantly correlated (correlation coefficient = 0.81, 0.44, 0.56; p values < 0.01, 0.03, 0.01, respectively).

CONCLUSION

Spot urine concentrations of morphine and its metabolites were highly correlated to those of serum. Total dose of daily morphine was related to both serum and urine concentration of morphine and its metabolites.

Opioid Concentrations in Oral Fluid and Plasma in Cancer Patients With Pain

CONTEXT

Measuring opioid concentrations in pain treatment is warranted in situations where optimal opioid analgesia is difficult to reach.

OBJECTIVES

To assess the usefulness of oral fluid (OFL) as an alternative to plasma in opioid concentration monitoring in cancer patients on chronic opioid therapy.

METHODS

We collected OFL and plasma samples from 64 cancer patients on controlled-release (CR) oral morphine, CR oral oxycodone, or transdermal (TD) fentanyl for pain. Samples were obtained on up to five separate days.

RESULTS

A total of 213 OFL and plasma samples were evaluable. All patients had detectable amounts of the CR or TD opioid in both plasma and OFL samples. The plasma concentrations of oxycodone and fentanyl (determination coefficient R(2) = 0.628 and 0.700, respectively), but not morphine (R(2) = 0.292), were moderately well correlated to the daily opioid doses. In contrast to morphine and fentanyl (mean OFL/plasma ratio 2.0 and 3.0, respectively), the OFL oxycodone concentrations were significantly higher than the respective plasma concentrations (mean OFL/plasma ratio 14.9). An active transporter could explain the much higher OFL vs. plasma concentrations of oxycodone compared with morphine and fentanyl.

CONCLUSION

OFL analysis is well suited for detecting the studied opioids. For morphine and fentanyl, an approximation of the plasma opioid concentrations is obtainable, whereas for oxycodone, the OFL/plasma concentration relationship is too variable for reliable approximation results.

Would legalizing illicit opioids reduce overdose fatalities? Implications from a natural experiment

Overdose is the leading cause of premature mortality among heroin users. We examine whether the provision of regulated and quality-controlled heroin to users in specified doses would reduce heroin overdose rates. We also address this in the context of the epidemic of prescription opioid use and deaths seen in recent years in the United States and internationally. We explore the extent to which any change in legal access to heroin would affect overdose rates, and note that this depends upon the validity of the two main assumptions that variations in illicit drug purity and/or the presence of drug contaminants are major causes of overdose. Toxicological and demographic data from studies of heroin overdose deaths do not support these assumptions. The surge in the use of pharmaceutical opioids provides an example of the legal delivery of opioids of known dosage and free of contaminants, where overdose deaths can be examined to test these assumptions. Rates of fatal opioid overdose have escalated, with increased rates of prescribing of pharmaceutical opioids. On the basis of the experience with prescription opioids, unregulated legal heroin access would not reduce overdose rates.

Fatalities temporally associated with the ingestion of ibogaine

Ibogaine is a naturally occurring psychoactive plant alkaloid that is used globally in medical and nonmedical settings for opioid detoxification and other substance use indications. All available autopsy, toxicological, and investigative reports were systematically reviewed for the consecutive series of all known fatalities outside of West Central Africa temporally related to the use of ibogaine from 1990 through 2008. Nineteen individuals (15 men, four women between 24 and 54 years old) are known to have died within 1.5-76 h of taking ibogaine. The clinical and postmortem evidence did not suggest a characteristic syndrome of neurotoxicity. Advanced preexisting medical comorbidities, which were mainly cardiovascular, and/or one or more commonly abused substances explained or contributed to the death in 12 of the 14 cases for which adequate postmortem data were available. Other apparent risk factors include seizures associated with withdrawal from alcohol and benzodiazepines and the uninformed use of ethnopharmacological forms of ibogaine.

Unintentional overdose and suicide among substance users: a review of overlap and risk factors

Substance use is a risk factor for suicide, suicide attempts, and fatal and non-fatal overdose, but to date, little has been done to integrate the research on suicidal behavior and overdose among substance users. This study reviews the literature on suicide and overdose among substance users with the goal of illuminating the similarities and differences between these two events. A structured review resulted in 15 articles (describing 14 unique studies) published between 1990 and 2010 that examined both overdose and suicide in samples of substance users. There is some evidence that substance users who attempt suicide are more likely to report an overdose and vice versa. This relationship may be partially explained by the fact that overdose is a common method of suicide. The results of the literature review also indicate that substance users with a history of both events may represent a group with particularly poor psychological and social functioning and severe drug-related problems. Further research is needed to understand the overlap of, and differences between, suicide and accidental overdose among individuals who misuse substances, particularly individuals who primarily use substances other than heroin. An improved understanding of the interrelationships between suicide and unintentional overdose among individuals who use alcohol or drugs is necessary to guide the development of effective prevention and intervention approaches.

Drug poisoning deaths in Sweden show a predominance of ethanol in mono-intoxications, adverse drug-alcohol interactions and poly-drug use

Over a 10-year period (1998-2007) all deaths in Sweden classified by forensic pathologists as fatal drug poisonings (N = 6894) were retrieved from a toxicology database (TOXBASE) belonging to the National Board of Forensic Medicine. The deaths were further classified as suicides N = 2288 (33%), undetermined N = 2260 (33%) and accidental N = 2346 (34%). The average age (± SD) of all victims was 49.1 ± 15.9 years and men 47.4 ± 15.6 years were 5-year younger than women 52.2 ± 15.8 years (p < 0.01). Most of the deceased (78%) were poly-drug users although a single drug (mono-intoxications) was found in 22% of all poisoning deaths (p < 0.001). The number of drugs in blood samples varied from 1 to 12 with a median of 3-4 per case. Mono-intoxication deaths were mostly ethanol-related (N = 976) and the mean and median blood-alcohol concentration (BAC) was 3.06 g/L and 3.10 g/L, respectively. The BAC decreased as the number of additional drugs in blood increased from 2.15 g/L with one drug to 1.25 g/L with 6 or more drugs. The mean (median) concentrations of non-alcohol drugs in mono-intoxication deaths were morphine (N = 93) 0.5mg/L (0.2mg/L), amphetamine (N = 39) 2.0mg/L (1.2mg/L), dextropropoxyphene (N = 33) 3.9 mg/L (2.9 mg/L), dihydro-propiomazine (N = 32) 1.6 mg/L (1.0mg/L) and 7-amino-flunitrazepam (N = 28), 0.4 mg/L (0.3mg/L). Elevated blood morphine in these poisoning deaths mostly reflected abuse of heroin as verified by finding 6-monoacetyl morphine (6-MAM) in the blood samples. When investigating drug poisoning deaths a comprehensive toxicological analysis is essential although the results do not reveal the extent of prior exposure to drugs or the development of pharmacological tolerance. The concentrations of drugs determined in post-mortem blood are one element in the case. The autopsy report, the police investigation, the findings at the scene and eye-witness statements should all be carefully considered when the cause and manner of death are determined.

Morphine is an arteriolar vasodilator in man

AIM

The mechanisms of action of morphine on the arterial system are not well understood. The aim was to report forearm vascular responses, and their mediation, to intra-arterial morphine in healthy subjects.

METHODS

Three separate protocols were performed: (i) dose ranging; (ii) acute tolerance; (iii) randomized crossover mechanistic study on forearm blood flow (FBF) responses to intrabrachial infusion of morphine using venous occlusion plethysmography. Morphine was infused either alone (study 1 and 2), or with an antagonist: naloxone, combined histamine-1 and histamine-2 receptor blockade or during a nitric oxide clamp.

RESULTS

Morphine caused an increase in FBF at doses of 30 microg min(-1)[3.25 (0.26) ml min(-1) 100 ml(-1)][mean (SEM)] doubling at 100 microg min(-1) to 5.23 (0.53) ml min(-1) 100 ml(-1). Acute tolerance was not seen to 50 microg min(-1) morphine, with increased FBF [3.96 (0.35) ml min(-1) 100 ml(-1)] (P = 0.003), throughout the 30-min infusion period. Vasodilatation was abolished by pretreatment with antihistamines (P = 0.008) and the nitric oxide clamp (P < 0.001), but not affected by naloxone. The maximum FBF with pretreatment with combined H1/H2 blockade was 3.06 (0.48) and 2.90 (0.17) ml min(-1) 100 ml(-1) after 30 min, whereas with morphine alone it reached 4.3 (0.89) ml min(-1) 100 ml(-1).

CONCLUSIONS

Intra-arterial infusion of morphine into the forearm circulation causes vasodilatation through local histamine-modulated nitric oxide release. Opioid receptor mechanisms need further exploration.

The context of illicit drug overdose deaths in British Columbia, 2006

Background

Illicit drug overdose deaths (IDD) relate to individual drug dose and context of use, including use with other drugs and alcohol. IDD peaked in British Columbia (BC) in 1998 with 417 deaths, and continues to be a public health problem. The objective of this study was to examine IDD in 2006 in BC by place of residence, injury and death, decedents' age and sex and substances identified.

Methods

IDD data was obtained through the BC Coroners Office and entered into SPSS (version 14). Fisher's exact and Pearson's χ² were used for categorical data; Mann-Whitney U-test for continuous variables. Rates were calculated using 2006 population estimates.

Results

We identified 223 IDD in BC; 54 (24%) occurred in Vancouver. Vancouver decedents (compared to those occurring outside Vancouver) were older (mean age 43.9 vs. 39.2 years; p < 0.01) and more likely to be male (90.7% vs. 77.5%; p = 0.03). Provincially Aboriginal ethnicity was reported for 19 deaths; 13 (30.2%) of 43 females and 6 (3.3%) of 180 males (p = < 0.001).

Cocaine was identified in 80.3%, opiates 59.6%, methadone 13.9%, methamphetamine/amphetamine 6.3%, and alcohol in 22.9% of deaths. Poly-substance use was common, 2 substances were identified in 43.8% and 3 or more in 34.5% of deaths. Opiates were more frequently identified in Vancouver compared to outside Vancouver (74.1% vs. 55.0%) p = 0.015.

Conclusion

Collaboration with the Coroner's office allowed us to analyze IDD in detail including place of death; cocaine, opiates and poly-substance use were commonly identified. Poly-substance use should be explored further to inform public health interventions.

Factors associated with history of non-fatal overdose among opioid users in the Swedish criminal justice system

BACKGROUND

Overdose (OD) is a common cause of death in opioid users. Also, many current opioid users report a history of non-fatal OD. The present study aimed to identify factors associated with a history of non-fatal OD.

METHODS

A sample of 7085 Swedish criminal justice clients with alcohol or drug misuse was assessed, using the Addiction Severity Index. Subjects reporting use of opioids during the 30 days prior to incarceration were included (n=1113). Relevant variables of misuse pattern, heredity, psychiatric symptoms and previous criminal charges were analysed in a logistic regression model.

RESULTS

A history of non-fatal OD was reported by 55% (n=604). The estimated contribution to the variance in OD history was 25% for variables describing misuse pattern, compared to 10% for psychiatric symptoms, 8% for heredity, and 8% for previous criminal charges. The final model included the following variables: history of injection drug use (OR 3.28), history of heroin use (OR 2.87), history of suicide attempt (OR 1.92), history of tranquilliser use (OR 1.91), being born in Sweden or other Nordic countries (OR 1.74), difficulty in controlling violent behaviour (OR 1.68), and paternal alcohol problems (OR 1.57).

CONCLUSIONS

Suicide attempts and difficulty in controlling violent behaviour were associated with history of non-fatal OD, independent of variables of misuse pattern. This may indicate a possible association with impulse control disturbances, and may have clinical applications. Country of birth and heredity of alcohol problems also had some influence. As expected, severity of misuse most strongly contributed to history of non-fatal OD.

Comparative toxicology of fatal heroin overdose cases and morphine positive homicide victims

AIMS

To compare the blood toxicology of heroin overdose cases and morphine positive homicide victims.

DESIGN

Analysis of coronial cases.

SETTING

Sydney, Australia. Cases A total of 705 cases of death due to opioid toxicity and 28 morphine positive homicide cases (1 January 1998-31 December 2002).

FINDINGS

There was no significant difference between the median morphine concentrations of the overdose and homicide groups (0.50 versus 0.45 mg/l). The overdose group was more likely to have blood alcohol (OR 3.21) present, but less likely to have methadone (OR 0.26) and cannabis (OR 0.04). There was a significant negative correlation between blood morphine and alcohol concentrations among the overdose group (rho = -0.32), but not among the homicide group (rho = -0.03). Independent predictors of a higher blood morphine concentration were a lower alcohol concentration and a higher methadone concentration.

CONCLUSIONS

Morphine concentrations per se are not diagnostic of overdose. The study confirms the salience of concomitant alcohol consumption in such events.

Sustained-release naltrexone: novel treatment for opioid dependence

The devastating costs of opioid abuse and dependence underscore the need for effective treatments for these disorders. At present, several different maintenance medications exist for treating opioid dependence, including methadone, buprenorphine and naltrexone. Of these, naltrexone is the only one that possesses no opioid agonist effects. Instead, naltrexone occupies opioid receptors and prevents or reverses the effects produced by opioid agonists. Despite its clear pharmacologic effectiveness, its clinical effectiveness in treating opioid dependence has been disappointing, primarily due to non-compliance with taking the medication. However, the recent availability of sustained-release formulations of naltrexone has renewed interest in this medication. The present paper describes the development of sustained-release naltrexone formulations and discusses the clinical issues associated with their use in treating opioid dependence.

Alcohol and cocaine use and abuse among opioid addicts engaged in a methadone maintenance treatment program

Alcohol and cocaine abuse result in unsatisfactory treatment outcomes for heroin and illicit opioid addicts engaged in Methadone Maintenance Treatment Programs (MMTPs). This study aims to clarify the impact of MMT, which focuses on cessation of opioid abuse and diminishing psychopathology to acceptable levels (stabilization) on alcohol and cocaine abuse. Of specific interest was whether reduction of polysubstance abuse and associated psychopathological complications diminished illicit opioid abuse and/or increased retention in treatment. Changes in cocaine and alcohol use that occurred in 53 heroin addicts who had been stabilized were monitored. A control group was composed of patients terminated from treatment due to noncompliance with treatment recommendations, poor attendance, or failure to have opioid abuse stabilized, within a year. The association of psychiatric severity with alcohol and cocaine abuse in these methadone maintained patients was assessed. Cessation of illicit opioid abuse and retention in treatment are positively correlated with decrease in alcohol and cocaine abuse and the absence of the psychosocial complications associated with such abuse.

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.

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.

Take-home naloxone to reduce heroin death

BACKGROUND

This paper reviews the relevant literature related to the distribution of take-home naloxone.

METHODS

A Medline search was conducted on articles published between January 1990 and June 2004 to identify scientific literature relevant to this subject. Those publications were reviewed, and from them other literature was identified and reviewed.

RESULTS

The prevalence, pathophysiology and circumstances of heroin overdose, and also bystander response are included in this review. Naloxone peer distribution has been instituted to varying degrees in the United States, Italy, Spain, Germany and the United Kingdom.

CONCLUSION

At this point the evidence supporting naloxone distribution is primarily anecdotal, although promising. Although the distribution of naloxone holds promise for further reducing heroin overdose mortality, problems remain. Naloxone alone may be insufficient in some cases to revive the victim, and cardiopulmonary resuscitation (CPR), especially rescue breathing, may also be needed. A second dose of naloxone might be necessary. Complications following resuscitation from overdose may infrequently need in-hospital care. Mortality from injecting without anyone else present will be unaffected by take-home naloxone. Take-home naloxone should be studied in a rigorous scientific manner.

The relationship between naloxone dose and key patient variables in the treatment of non-fatal heroin overdose in the prehospital setting

OBJECTIVES

To examine the relationship between key patient variables and variation in naloxone dose (from the standard dose of 1.6 mg IMI) administered by ambulance paramedics in the prehospital management of heroin overdose.

METHODS

A retrospective analysis of 7985 ambulance patient care records of non-fatal heroin overdose cases collected in greater metropolitan Melbourne. The main outcome measure was the dose of intramuscular naloxone required to increase the level of consciousness and the respiratory rate in patients presenting with suspected heroin overdose. Key patient variables influencing the dose that were recorded included: age, sex, initial patient presentation and reported concurrent alcohol use.

RESULTS

Multinomial logistic regression revealed that patients with higher levels of consciousness and respiratory rates on arrival of the paramedic crew were more likely to receive a less than standard dose of naloxone. Conversely, patients with lower levels of consciousness and low respiratory rates received greater than standard doses of naloxone for resuscitation. Patients who received greater than the standard dose of naloxone were 2.25 (95% CI, 1.83-2.77) times more likely to have been under the influence of alcohol when consuming the heroin that resulted in overdose.

CONCLUSIONS

The concurrent use of alcohol with heroin resulted in the use of greater than standard doses of naloxone by paramedics in resuscitating overdose patients. It is possible that the higher dose of naloxone is required to reverse the combined effects of alcohol and heroin. There was also a link between initial patient presentation and the dose of naloxone required for resuscitation. In light of these findings, it would appear that initial patient presentation and evidence of alcohol use might be useful guides as to providing the most effective dose of naloxone in the prehospital setting.

Reducing hospital presentations for opioid overdose in patients treated with sustained release naltrexone implants

BACKGROUND

Non-fatal overdoses represent a significant morbidity for regular heroin users. Naltrexone is an opioid antagonist capable of blocking the effects of heroin, thereby preventing accidental overdose. However, treatment with oral naltrexone is often associated with non-compliance. An alternative is the use of a sustained release preparation of naltrexone. The aim of this study was to assess the change in number of opioid and other drug overdoses in a large cohort of heroin dependent persons (n=361; 218 males) before and after treatment with a sustained release naltrexone implant. A sub-group of this cohort (n=146; 83 males) had previously received treatment with oral naltrexone, which also allowed a comparison of overdoses pre- and post-oral and also post-implant treatments.

METHOD

We used a pre-post design, with data prospectively collected via the West Australian Health Services Research Linked Database, and the Emergency Department Information System. Participants were treated under the Australian Therapeutic Goods Administration's special access guidelines.

RESULTS

Most (336, 93%) of the cohort was in one or both databases. We identified 21 opioid overdoses involving 20 persons in the 6 months pre-treatment that required emergency department presentation or hospital admission: none were observed in the 6 months post-treatment. This is consistent with the existing pharmacokinetic data on this implant, which indicates maintenance of blood naltrexone levels at or above 2 ng/ml for approximately 6 months. A reduced number of opioid overdoses were also observed 7-12 months post-implant. The study found a significant increase in sedative "overdoses", some of which occurred in the 10 days following implant treatment and were likely associated with opioid withdrawal and/or implant treatment. For those previously treated with oral naltrexone, more opioid overdoses occurred in both the 6-months prior to and after oral compared to the 6-months post-implant treatment.

CONCLUSIONS

The findings support the clinical efficacy of this sustained release naltrexone implant in preventing opioid overdose. However, given the high prevalence of poly-substance use among dependent heroin users, programs offering this type of treatment should also focus on preventing, detecting and managing poly-substance use.

A case report: Pavlovian conditioning as a risk factor of heroin 'overdose' death

BACKGROUND

The authors present a case illustrating a mechanism leading directly to death which is not rare but has received little attention.

CASE PRESENTATION

The case was evaluated by autopsy, investigation of morphine concentration in the blood, and clinical data. The heroin dose causing the 'overdose' death of a young man who had previously been treated a number of times for heroin addiction did not differ from his dose of the previous day taken in the accustomed circumstances. The accustomed dose taken in a strange environment caused fatal complications because the conditioned tolerance failed to operate. The concentration of morphine in the blood did not exceed the level measured during earlier treatment.

CONCLUSION

These results are in line with the data in the literature indicating that morphine concentrations measured in cases of drug-related death do not differ substantially from those measured in cases where the outcome is not fatal. A knowledge of the conditioning mechanism can contribute to prevention of fatal cases of a similar type. The harm reduction approach places great stress on preventive intervention based on data related to drug-related death.

Transient changes in behaviour lead to heroin overdose: results from a case-crossover study of non-fatal overdose

BACKGROUND AND AIMS

Heroin overdose is a serious consequence of heroin use and one of the leading causes of premature death and illness in Australia. Despite considerable research effort little is known about the effects of transient changes in heroin user behaviour and the links to overdose. This research is the first to use a suitable methodology to allow such ephemeral changes and their effects on non-fatal heroin overdose to be examined.

METHODS

A case-crossover design was used in which non-fatal heroin overdose survivors' recall of risk behaviours in the 12 hours prior to overdose (hazard period) was compared to their recall of risk behaviours in the 12 hours prior to a selected non-overdose heroin injection (control period).

RESULTS

A total of 155 participants were able to provide valid details of hazard and control periods. A dose-response relationship was observed between the self-reported amount of heroin used and likelihood of overdose (e.g. > AUD50, OR 12.97, 95% CI 2.54-66.31). The use of benzodiazepines (OR 28, 95% CI 3.81-205.79) or alcohol (OR 2.88, 95% CI 1.29-6.43), during the hazard period was related to overdose risk, but the effect of alcohol was attenuated by the effect of benzodiazepines. Shifting from private to public locations between control and hazard periods was also related to increased risk of overdose (OR 3.63, 95% CI 1.66-7.93).

CONCLUSIONS

We demonstrate the value of a new methodology to explore heroin overdose, as well as discussing its limitations and ways to overcome them in future. In terms of our findings, overdose prevention messages need to highlight the impact of these transient changes in behaviour and to emphasize the risks of using higher doses of heroin as well as continuing to emphasize the risks of combining heroin with other central nervous system (CNS) depressants. Safer environments for heroin use, such as injecting rooms, may also reduce the chances of overdose.

Effects of seven drugs of abuse on action potential repolarisation in sheep cardiac Purkinje fibres

Seven drugs of abuse have been examined for effects on the action potential in sheep isolated cardiac Purkinje fibres. Phencyclidine (5 microM) induced a significant increase (30.7%) in action potential duration at 90% repolarisation (APD(90)). Similarly, 10 microM 3,4-methylenedioxymethamphetamine (MDMA, 'Ecstasy') induced a significant increase in APD(90) of 12.1%. Although Delta(9)-tetrahydrocannabinol (0.1 microM) induced a small, but statistically significant, 4.8% increase in APD(90), no effects were observed at 0.01 or 1 microM. Cocaethylene (10 microM) induced a significant shortening of APD(90) (-23.8%). Cocaine (up to 1 microM), (+)-methamphetamine ('Speed'; up to 5 microM), and the heroin metabolite, morphine (up to 5 microM), had no statistically significant effects. The possible significance of these findings is discussed in the context of other recognised cardiac effects of the tested drugs.

Blood free morphine levels vary with concomitant alcohol and benzodiazepine use

AIMS

To record the concentration of morphine in post-mortem blood samples from fatalities arising directly from illicit drug abuse in Grampian, Scotland and to explore whether there is any difference in the morphine levels with co-existent drugs especially alcohol and benzodiazepines.

METHODS

Drug-related deaths that had positive blood toxicology for morphine from the beginning of January 1995 until the end of December 2001 were identified from the database of toxicological data held in the Department of Clinical Biochemistry, Aberdeen Royal Infirmary, and the data analysed in conjunction with the information in the files of the Forensic Medicine Unit, University of Aberdeen.

RESULTS

One hundred and twenty-six cases were identified and consisted of 106 males and 20 females with an age range 17-51 (Median 26 years). Morphine was the single isolate in only 21 cases giving a median blood free morphine (BFM) of 0.19 mg/L. When morphine and benzodiazepines were the primary isolates [Formula: see text] the median BFM was 0.37 mg/L, and when morphine was in combination with alcohol [Formula: see text] the median BFM was 0.18 mg/L. Statistical significance was noted between these groups ( [Formula: see text] ). The remaining 59 cases had morphine combined with other drugs.

CONCLUSIONS

In the studied cases, the concentrations of BFM were statistically higher when morphine was only isolated in conjunction with benzodiazepines than when combined only with alcohol. These results may be multi-factorial; user error while under drug influence, the individuals drug tolerance, or related to the pharmacokinetics of morphine and its interactions with alcohol and benzodiazepines. Our understanding of the interactions of these substances appears to be far from clear.

Adverse events after naloxone treatment of episodes of suspected acute opioid overdose

OBJECTIVE

An increasing and serious heroin overdose problem in Oslo has mandated the increasing out-of-hospital use of naloxone administered by paramedics. The aim of this study was to determine the frequencies and characteristics of adverse events related to this out-of-hospital administration by paramedics.

METHODS

A one-year prospective observational study from February 1998 to January 1999 was performed in patients suspected to be acutely overdosed by an opioid. A total of 1192 episodes treated with naloxone administered by the Emergency Medical Service system in Oslo, were included. The main outcome variable was adverse events observed immediately after the administration of naloxone.

RESULTS

The mean age of patients included was 32.6 years, and 77% were men. Adverse events suspected to be related to naloxone treatment were reported in 45% of episodes. The most common adverse events were related to opioid withdrawal (33%) such as gastrointestinal disorders, aggressiveness, tachycardia, shivering, sweating and tremor. Cases of confusion/restlessness (32%) might be related either to opioid withdrawal or to the effect of the heroin in combination with other drugs. Headache and seizures (25%) were probably related to hypoxia. Most events were non-serious. In three episodes (0.3%) the patients were hospitalized because of adverse events.

CONCLUSION

Although adverse events were common among patients treated for opioid overdose in an out-of-hospital setting, serious complications were rare. Out-of-hospital naloxone treatment by paramedics seems to save several lives a year without a high risk of serious complications.

Social network correlates of self-reported non-fatal overdose

The leading cause of death among heroin users is drug overdose. The present study examined the relationship between history of self-reported drug overdoses and social network characteristics among cocaine and opiate users. Data were from cross-sectional surveys administered from March 2001 through February 2003 as part of follow-up of an experimental network oriented HIV prevention intervention. A total of 838 participants with histories of cocaine and opiate use completed the survey. Several social network variables were found to be significantly associated with drug overdose in the prior 2 years, including larger number of network members who were injection drug users and a larger number of conflictual ties among the network members. Even after controlling for age, gender, frequency of injection drug and alcohol use, and health status, network variables continued to have a strong association with history of recent overdose. These data suggest that large drug networks should be targeted for drug overdose prevention interventions.

Alcohol and non-fatal drug overdoses

The purpose of this study was to explore to what extent alcohol is a factor in non-fatal overdoses on the basis of records of ambulance emergencies, and to what extent this varies across gender and age. Furthermore, we wanted to investigate whether alcohol intake, in relation to an overdose, is associated with the risk of recurrent overdoses, and if so, whether such an association varies across gender and age. To investigate the role of alcohol intake in non-fatal overdoses, analyses were conducted both at the event level and at the individual level. Bivariate associations were explored in table analyses and by comparisons of means. To determine whether alcohol intake was associated with experiencing recurrent overdoses, survival analyses were conducted applying Kaplan-Meier estimation and Cox regression models. Furthermore, a linear regression model was estimated to assess the impact of gender age and number of overdoses on the proportion of overdoses in which alcohol was involved. Between groups of clients who had overdosed once, several times or many times, we found that there was a U-shaped relationship. The proportion of overdoses with alcohol involved was highest among those who had overdosed once and those who had overdosed more than ten times. The probability for a recurrent overdose was higher among those who were reported with no alcohol intake in the first overdose. Being female and having alcohol involved in the first overdose registered during our observation period reduced the risk for a recurrent overdose. However, age seemed to be a gradient with respect to alcohol's association with recurrent overdoses. While alcohol was associated with a significantly lower risk for recurrence in the two youngest age groups, this is not the case in the oldest age group. A possible explanation might be that it is a change in the pattern of drug use as an effect of aging where infrequent heroin use in combination with frequent alcohol intake increases with increasing age. For this type of drug users the individual's risk of recurrent overdoses may be lower due to fewer events of heroin intake.

Escalating morphine exposures followed by withdrawal in feline immunodeficiency virus-infected cats: a model for HIV infection in chronic opiate abusers

Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direct effects of opiates on HIV infection are difficult to determine epidemiologically, animal models of lentivirus infection are relied upon to study the effects of opiates in the absence of confounding factors. Morphine, the predominant metabolite of heroin, is used in most experimental systems examining heroin abuse. In this study, morphine treatment of feline immunodeficiency virus (FIV)-infected cats modeled a typical pattern of escalating drug use interspersed with withdrawals. Plasma cortisol levels were measured for evidence of stress associated with morphine withdrawal. In the morphine-treated cats, cortisol levels peaked at time points corresponding to morphine withdrawal and returned to baseline levels during treatment and several weeks after the final withdrawal. Morphine-treated cats displayed clear behavioral and physical signs of opiate exposure and evidence of withdrawal when the drug was stopped. Morphine-exposed cats did not experience enhanced severity of FIV-related disease; in fact, morphine demonstrated a protective effect on FIV-associated changes in brainstem auditory evoked potentials. Our research suggests that opiate exposure is unlikely to adversely affect the progression of acute lentivirus infection and might be beneficial in controlling associated neurological disease.

Blood morphine levels in naltrexone-exposed compared to non-naltrexone-exposed fatal heroin overdoses

The aim of this study was to investigate the association between prior exposure to naltrexone and increased risk of fatal heroin overdose using a review of toxicology reports for heroin-related fatalities between July 1997 to August 1999 for two groups: those treated with oral naltrexone and those who were not treated. Additional information for the oral naltrexone group was obtained from clinic files. Naltrexone-treated deaths were identified from the patient database at the Australian Medical Procedures Research Foundation (AMPRF), Perth, Western Australia (WA) through the Western Australian Department of Health, Data Linkage Project. Non-treated cases were identified from the database at the Forensic Science Laboratory, State Chemistry Centre (WA). We identified and investigated blood morphine concentrations following 21 fatal heroin overdoses with prior exposure to naltrexone and in 71 non-naltrexone-exposed cases over the same time period. The proportion of deaths where heroin use was a major contributing factor was little different in the non-naltrexone compared to the naltrexone-exposed group. Furthermore, in 'acute opiate toxicity' deaths, blood morphine levels were lower in non-naltrexone-exposed compared with naltrexone-exposed cases. Although there was a higher number of deaths designated as rapid (i.e. occurring within 20 minutes) in the naltrexone-exposed (89%) compared with the non-exposed group (72%) this was not statistically significant. Other drug use in relation to heroin-related fatalities is discussed. Findings do not support the hypothesis that prior exposure to naltrexone increases sensitivity to heroin toxicity.

Opiates, cocaine and alcohol combinations in accidental drug overdose deaths in New York City, 1990-98

AIMS

Accidental drug overdose contributes substantially to mortality among drug users. Multi-drug use has been documented as a key risk factor in overdose and overdose mortality in several studies. This study investigated the contribution of multiple drug combinations to overdose mortality trends.

DESIGN

We collected data on all overdose deaths in New York City between 1990 and 1998 using records from the Office of the Chief Medical Examiner (OCME). We standardized yearly overdose death rates by age, sex and race to the 1990 census population for NYC to enable comparability between years relevant to this analysis.

FINDINGS

Opiates, cocaine and alcohol were the three drugs most commonly attributed as the cause of accidental overdose death by the OCME, accounting for 97.6% of all deaths; 57.8% of those deaths were attributed to two or more of these three drugs in combination. Accidental overdose deaths increased in 1990-93 and subsequently declined slightly in 1993-98. Changes in the rate of multi-drug combination deaths accounted for most of the change in overdose death rates, whereas single drug overdose death rates remained relatively stable. Trends in accidental overdose death rates within gender and racial/ethnic strata varied by drug combination suggesting different patterns of multi-drug use among different subpopulations.

CONCLUSIONS

These data suggest that interventions to prevent accidental overdose mortality should address the use of drugs such as heroin, cocaine and alcohol in combination.

Fatal heroin-related overdose in San Francisco, 1997-2000: a case for targeted intervention

Heroin-related overdose is the single largest cause of accidental death in San Francisco. We examined demographic, location, nontoxicological, and toxicological characteristics of opiate overdose deaths in San Francisco, California. Medical examiner's case files for every opioid-positive death from July 1, 1997, to June 30, 2000, were reviewed and classified as overdose deaths or other. Demographic variables were compared to two street-based studies of heroin users and to census data. From 1997 to 2000, of all heroin-related overdoses in San Francisco, 47% occurred in low-income residential hotels; 36% occurred in one small central area of the city. In 68% of deaths, the victim was reportedly alone. When others were present between last ingestion of heroin and death, appropriate responses were rare. In three cases, police arrested the person who called emergency services or others present on the scene. We recommend the development of overdose response training targeted at heroin users and those close to them, including the staff of residential hotels.

Heroin overdose: research and evidence-based intervention

Drug overdose is a major cause of premature death and morbidity among heroin users. This article examines recent research into heroin overdose to inform interventions that will reduce the rate of overdose death. The demographic characteristics of overdose cases are discussed, including factors associated with overdose: polydrug use, drug purity, drug tolerance, routes of administration, and suicide. Responses by heroin users at overdoses are also examined. Potential interventions to reduce the rate of overdose and overdose-related morbidity are examined in light of the emerging data in this field.

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

AIMS

To test the hypothesis that methadone is responsible for a greater increase in overdose deaths than heroin, and causes proportionally more overdose deaths than heroin at weekends.

DESIGN AND SETTING

Multivariate analysis of 3961 death certificates mentioning heroin, morphine and/or methadone held on the Office for National Statistics drug-related poisoning mortality database from 1993 to 1998 in England and Wales.

MEASUREMENTS

Percentage increase in deaths by year by drug, odds ratio (OR) of dying at the weekend from methadone-related overdose compared to dying from heroin/morphine overdose.

FINDINGS

From 1993 to 1998, annual opiate overdose deaths increased from 378 to 909. There was a 24.7% (95% confidence interval (CI) 22-28%) yearly increase in heroin deaths compared to 9.4% (95% CI 6-13%) for methadone only. This difference was significant (P < 0.001 by test of interaction) after adjustment for sex, age group, polydrug use, area of residence and underlying cause of death. The largest number of deaths occurred on Saturday (673). The OR of death from methadone overdose on Saturday and Sunday was 1.48 (95% CI 1.29-1.71) for methadone-only deaths compared to dying from heroin/morphine at the weekend after adjustment for other covariates, but the OR was not significant (1.09, 95% CI 0.95-1.25) if the weekend was defined as Friday and Saturday.

CONCLUSIONS

There was no evidence that the threefold increase in deaths over time was due to methadone. There was equivocal support only for the hypothesis that there was an excess of deaths from methadone at weekends. Increased interventions to prevent overdose among injectors in England and Wales are long overdue.

Use of morphine and 6-monoacetylmorphine in blood for the evaluation of possible risk factors for sudden death in 192 heroin users

AIMS

To detect risk factors for sudden death from heroin injection.

DESIGN

Evaluation of data from forensic investigations of all fatal cases of suspected heroin death in a metropolitan area. Only cases with detectable morphine and 6-monoacetylmorphine (6-MAM) in blood were included in order to select heroin intoxication cases.

SETTING

Stockholm, Sweden.

MEASUREMENTS

Autopsy investigation and toxicological analysis of blood and urine; and police reports.

FINDINGS

In two-thirds of the 192 cases, death occurred in public places, and mostly without any time delay. Blood concentrations of morphine ranged from 50 to 1200 ng/g, and of 6-MAM from 1 to 80 ng/g. Codeine was detected in 96% of the subjects. In the majority of cases the forensic investigation indicated polydrug use, the most common additional findings being alcohol and benzodiazepines. However, in one-quarter of the cases other drug combinations were found. Previous abstinence from heroin and use of alcohol were identified as risk factors. For 6-MAM there was also a correlation with the presence of THC and benzodiazepines. Despite a high frequency of heart abnormalities (e.g. myocarditis and focal myocardial fibrosis), these conditions did not correlate with morphine or 6-MAM blood concentrations.

CONCLUSIONS

We confirm that alcohol intake and loss of tolerance are risk factors for death from heroin use, whereas no connection to heart pathology was observed. Further, prospective, studies should focus on other possible risk factors.

Do Co‐intoxicants Increase Adverse Event Rates in the First 24 Hours in Patients Resuscitated from Acute Opioid Overdose?

BACKGROUND

Patients frequently arrive in emergency departments (EDs) after being resuscitated from opioid overdose. Autopsy studies suggest that multidrug intoxication is a major risk factor for adverse outcomes after acute heroin overdose in patients. If this is true, there may be high-risk drug combinations that identify patients who require more intensive monitoring and prolonged observation. Our objective was to determine the impact of co-intoxication with alcohol, cocaine, or CNS depressant drugs on short-term adverse event rates in patients resuscitated from acute opioid overdose.

METHODS

Data were extracted from the database of a prospective opioid overdose cohort study conducted between May 1997 and 1999. Patients were prospectively enrolled if they received naloxone for presumed opioid overdose. Investigators gathered clinical, demographic, and other predictor variables, including co-intoxicants used. Patients were followed to identify prespecified adverse outcome events occurring within 24 h, and multiple logistic regression was used to determine the association of concomitant drug use on short-term adverse event rates.

RESULTS

Of 1155 patients studied, 58 (5%) had pure opioid overdose and 922 (80%) reported co-intoxicants, including alcohol, cocaine, and CNS depressants. Overall, out of 1056 patients with known outcome status there were 123 major adverse events (11.6%) and 194 minor adverse events (18.4%). After adjustment for age, gender, HIV status, cardiovascular disease, pulmonary disease and diabetes, we found that coadministration of alcohol, cocaine, or CNS depressants, alone or in combination, was not associated with increased risk of death or adverse events during the 24 h follow-up period.

CONCLUSION

In patients resuscitated from acute opioid overdose, short-term outcomes are similar for patients with pure opioid overdose and multidrug intoxications. A history of cointoxication cannot be used to identify high-risk patients who require more intensive ED monitoring or prolonged observation.

Perceived addiction treatment needs among alcohol using injection drug users

Hazardous drinking is common among active injection drug users (IDUs). This report examines: (1) the perceived alcohol and drug treatment needs of a cohort of IDUs, and (2) whether perceived needs predict treatment entry. One hundred and eighty-seven AUDIT-positive (> or = 8), active IDUs were recruited between 2/98-10/99 for the Brief Alcohol Intervention for Needle Exchangers (BRAINE) trial. At entry, about 18% of participants perceived no need for substance abuse treatment, 52% for drug treatment alone, 26% for drug and alcohol treatment, and only 3% a need for alcohol treatment only. Very high levels of drinking and adverse drinking consequences were observed among those perceiving no need for treatment of alcohol problems. Perceived need for alcohol treatment was positively associated with measures of adverse drinking consequences and DSM-IV diagnosis for alcohol dependence. Persons who at baseline perceived the need for alcohol treatment were more likely to enter alcohol treatment at 6-month follow-up than those without a perceived need (20% vs. 5%; p = .006). We conclude that IDUs with co-occurring alcohol-use disorders perceive alcohol treatment needs as less immediate than drug treatment. Because perceived need predicts treatment entry, changing alcohol treatment perceptions in IDUs promises the potential of significant long-term public health benefits.

Fatal versus non-fatal heroin "overdose": blood morphine concentrations with fatal outcome in comparison to those of intoxicated drivers

The study was performed to distinguish fatal from non-fatal blood concentrations of morphine. For this purpose, blood levels of free morphine and total morphine (free morphine plus morphine conjugates) in 207 cases of heroin-related deaths were compared to those in 27 drivers surviving opiate intoxication. The majority of both survivors and non-survivors were found to show a concomitant use of depressants including alcohol or stimulants. Blood morphine levels in both groups varied widely, with a large area of overlap between survivors (free morphine: 0-128 ng/ml, total morphine: 10-2,110 ng/ml) and non-survivors (free morphine: 0-2,800 ng/ml, total morphine: 33-5,000 ng/ml). Five (18.5%) survivors and 87 (42.0%) non-survivors exhibit intoxication only by morphine. In these cases, too, both groups overlapped (survivors-free morphine: 28-93 ng/ml, total morphine: 230-1,451 ng/ml; non-survivors-free morphine: 0-2,800 ng/ml, total morphine: 119-4,660 ng/ml). Although the blood levels of free or total morphine do not allow a reliable prediction of survival versus non-survival, the ratio of free/total morphine may be a criterion to distinguish lethal versus survived intoxication. The mean of the ratio of free to total morphine for all lethal cases (N=207) was 0.293, for those that survived (N=27) 0.135, in cases of intoxication only by morphine 0.250 (N=87) and 0.080 (N=5), respectively. Applying a cut-off of 0.12 for free/total morphine and performing ROC analyses, fatal outcome can be predicted in 80% of the cases correctly, whereas 16% of the survivors were classified as dead. Nevertheless, in this study, all cases with a blood concentration of 200 ng/ml and more of free morphine displayed a fatal outcome.

Hair morphine concentrations of fatal heroin overdose cases and living heroin users

AIMS

To compare heroin and other opiate use of heroin overdose fatalities, current street heroin users and drug-free therapeutic community clients.

DESIGN

Hair morphine concentrations that assess heroin use and other opiate use in the 2 months preceding interview or death were compared between heroin overdose fatalities diagnosed by forensic pathologists (FOD) (n = 42), current street heroin users (CU) (n = 100) and presumably abstinent heroin users in a drug-free therapeutic community (TC) (n = 50).

SETTING

Sydney, Australia.

FINDINGS

The mean age and gender breakdown of the three samples were 32.3 years, 83% male (FOD), 28.7 years, 58% male (CU) and 28.6 years, 60% male (TC). The median blood morphine concentration among the FOD cases was 0.35 mg/l, and 82% also had other drugs detected. There were large differences between the three groups in hair morphine concentrations, with the CU group (2.10 ng/mg) having concentration approximately four times that of the FOD group (0.53 ng/mg), which in turn had a concentration approximately six times that of the TC group (0.09 ng/mg). There were no significant differences between males and females in hair concentrations within any of the groups. Hair morphine concentrations were correlated significantly with blood morphine concentrations among FOD cases (r = 0.54), and self-reported heroin use among living participants (r = 0.57).

CONCLUSIONS

The results indicate that fatal cases had a lower degree of chronic opiate intake than the active street users, but they were not abstinent during this period.