Cocaine use in New South Wales, Australia, 1996-2000: 5 year monitoring of trends in price, purity, availability and use from the illicit drug reporting system

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

AIMS

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

DESIGN

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

SETTING

Australia-wide.

CASES

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

MEASUREMENTS

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

FINDINGS

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

CONCLUSIONS

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

Survey methods and characteristics of a sample of Aboriginal and Torres Strait Islander and non-Indigenous people who have recently used methamphetamine: the NIMAC survey

INTRODUCTION AND AIMS

There is a need for detailed information on methamphetamine use in Aboriginal and Torres Strait Islander communities. We describe a national survey on methamphetamine use among Aboriginal and Torres Strait Islander people and non-Indigenous people.

DESIGN AND METHODS

Participants aged 16 years or older who reported using methamphetamine in the past year were recruited for a cross-sectional survey through 10 Aboriginal Community Controlled Organisations. Surveys were completed anonymously on electronic tablets. Measures included the Australian Treatment Outcomes Profile, the Severity of Dependence Scale, subscales from Opiate Treatment Index and the Kessler 10. A Chronic Stress Scale was used to assess culturally situated chronic stress factors.

RESULTS

Of the 734 participants, 416 (59%) were Aboriginal or Torres Strait Islander and 331 (45%) were female. In the previous year, most participants reported smoking (48.7%) or injecting (34%) methamphetamine and 17.4% reported daily use. Aboriginal and Torres Strait Islander people did not differ significantly from non-Indigenous participants on methamphetamine use patterns (age at first use, frequency of use, main mode of use, injecting risk, poly drug use). Aboriginal and Torres Strait Islander participants felt less able to access health care (32% vs. 48%, P < 0.001), including mental health services (19% vs. 29%, P < 0.002), were less likely to report a mental health diagnosis (50% vs. 60%, P < 0.002) and were more likely to turn to family for support (52% vs. 34%, P < 0.001).

DISCUSSION AND CONCLUSIONS

We recruited and surveyed a large sample of Aboriginal and Torres Strait Islander people from which we can derive detailed comparative data on methamphetamine use and related health service needs for Aboriginal and Torres Strait Islander and non-Indigenous Australians.

High hepatitis C incidence in relation to prescription opioid injection and poly-drug use: Assessing barriers to hepatitis C prevention

BACKGROUND

Prescription opioid (PO) injection and poly-drug use have been associated with hepatitis C virus (HCV) infection among people who inject drugs (PWID). Poly-drug use is often a barrier to key HCV preventive programmes including opioid agonist treatment. The contribution of specific drug combinations to high HCV incidence in poly-drug users has not been assessed previously. Addressing this knowledge gap could enhance HCV treatment and prevention efforts. We examined the association between specific drugs and number of drugs used in addition to injected POs, and HCV seroconversion.

METHODS

PWID participating in a cohort study in Montréal (HEPCO), HCV-seronegative at baseline and followed between 2004 and 2013, were included. Data were collected by interview-administered questionnaires. Blood samples were tested for HCV new infections at each 3-6 month follow-up visit. Time-varying Cox regression models were utilized.

RESULTS

Of 356 participants (81.5% males; mean age: 34.7 years), 123 (34.6%) reported injected POs in the past month at baseline. In univariate analyses, recent use of the following drugs was associated with HCV seroconversion: injected POs, injected cocaine, injected heroin, non-injected tranquilisers, and smoked crack/cocaine. The relative excess risk of HCV seroconversion due to interaction (RER1_HR) was the highest for co-use of injected POs with the following substances: injected cocaine (RER1_HR=3.44), smoked crack/cocaine (RER1_HR=1.27), and non-injected tranquilisers (RER1_HR=0.8). In addition, a significant linear trend (p<0.001) towards higher risk was observed with increasing the number of these three drugs used in combination with injected POs.

CONCLUSION

Specific drugs and number of drugs used in addition to injected POs play a modulating role in the risk of HCV primary infection. Poly-drug use among people who inject POs has to be addressed in order to improve harm reduction programmes and reduce HCV transmission in this high-risk population.

The Sydney Medically Supervised Injecting Centre: Client Characteristics and Predictors of Frequent Attendance during the First 12 Months of Operation

This paper describes characteristics of clients registered in the first 12 months of the Sydney Medically Supervised Injecting Centre's (MSIC) operation, as well as predictors of frequent attendance. The study is based on information collected from clients at their initial registration and subsequent service utilization. Most of the 2,719 clients were male (71%), almost half had previously experienced at least one nonfatal heroin overdose, and one quarter had accessed formal drug treatment in the previous 12 months. Characteristics associated with frequent attendance at the MSIC were reporting previous attendance at the local primary health service for injection drug users (IDU), injecting drugs other than amphetamine, reporting sex work, injecting at least daily, and injecting in a public place in the month before registration.

Perceived risk of methamphetamine among Chinese methamphetamine users

BACKGROUND

Methamphetamine use has grown considerably in China in recent years. Information about perceptions of risk on methamphetamine is important to facilitate health promotion efforts.

METHODS

Using both survey data and qualitative interview data, the authors evaluate the perceived risk of methamphetamine use among Chinese users using a mixed-methods approach. Through Respondent Driven Sampling, the authors recruited a sample of 303 methamphetamine users in Changsha, China.

RESULTS

A majority (59.1%) perceive that infrequent methamphetamine use poses no risk to the user, while 11.2% perceive at least moderate risk for light use. A majority (56.7%) perceived at least moderate risk associated with regular methamphetamine use. Most (82.2%) also perceive methamphetamine to be easily obtainable. A path model indicates that perceived risk shapes intentions to use and expectations of future use, as does perceived availability. Qualitatively, while addiction was the most common risk discussed by users, they differed on whether they perceived the drug addictive. Other concerns raised by interviewees included impaired cognition, mental health problems, physical harm, and social dysfunction.

CONCLUSION

While some users identify significant risks with methamphetamine, others do not perceive its use to be problematic. Collectively, these findings indicate that intervening upon perceptions of risk among Chinese methamphetamine users may be a means to influence intentions to use.

Clinical features and correlates of outcomes for high-risk, marginalized mothers and newborn infants engaged with a specialist perinatal and family drug health service

Background. There is a paucity of research in Australia on the characteristics of women in treatment for illicit substance use in pregnancy and the health outcomes of their neonates. Aims. To determine the clinical features and outcomes of high-risk, marginalized women seeking treatment for illicit substance use in pregnancy and their neonates. Methods. 139 women with a history of substance abuse/dependence engaged with a perinatal drug health service in Sydney, Australia. Maternal (demographic, drug use, psychological, physical, obstetric, and antenatal care) and neonatal characteristics (delivery, early health outcomes) were examined. Results. Compared to national figures, pregnant women attending a specialist perinatal and family drug health service were more likely to report being Australian born, Aboriginal or Torres Strait Islander, younger, unemployed, and multiparous. Opiates were the primary drug of concern (81.3%). Pregnancy complications were common (61.9%). Neonates were more likely to be preterm, have low birth weight, and be admitted to special care nursery. NAS was the most prevalent birth complication (69.8%) and almost half required pharmacotherapy. Conclusion. Mother-infant dyads affected by substance use in pregnancy are at significant risk. There is a need to review clinical models of care and examine the longer-term impacts on infant development.

Increases in the availability of prescribed opioids in a Canadian setting

BACKGROUND

The nonmedical use of prescribed opioids (POs) has increased across North America over the past decade. Our objective was to identify changes in the availability of POs and other illicit drugs among drug users in a Canadian setting.

METHODS

Information on the availability of illicit drugs was collected in standardized interviews from a large observational research program involving illicit drug users in Vancouver, British Columbia from 2006 to 2010. The primary outcome was the perceived availability of a set of six POs (aspirin/oxycodone, hydromorphone, oxycodone, morphine, acetaminophen/codeine and methadone) among individuals reporting ever using POs. Availability was measured in three levels: not available, delayed availability (available ≥10 min), and immediate availability (available <10 min). Multivariate ordinal logistic regression models were executed to estimate the trend in PO availability, controlling for individual characteristics hypothesized to influence availability.

RESULTS

1871 individuals were followed during the study period (2006-2010), including 583 (31.2%) women. The availability of POs increased over time, regardless of changes in the characteristics of cohort entrants. These increases were observed while the availability of traditional drugs of abuse (e.g., heroin and cocaine) remained constant. The adjusted odds of delayed availability vs. unavailability were between 34% (hydromorphone) and 71% (acetaminophen/codeine) greater in each calendar year.

DISCUSSION

The availability of POs among drug users in a Canadian setting increased markedly over a relatively short timeframe, despite persistent and high availability of heroin and cocaine. Further study is required to determine the context of use of POs, associated harms, as well as policy responses to increasing availability.

Effect of prison-based opioid substitution treatment and post-release retention in treatment on risk of re-incarceration

AIMS

People who use heroin are frequently incarcerated multiple times. Reducing re-incarceration of this group is important for reducing both health risks associated with incarceration and the costs of correctional administration. Opioid substitution treatment (OST) in prisons may help to reduce re-incarceration, but research findings on this topic have been mixed. In this study, we examined the effect of OST in prison and after release on re-incarceration.

DESIGN

Longitudinal cohort study. SETTING, PARTICIPANTS AND MEASUREMENTS: Data on OST and incarceration were linked for a cohort of 375 male heroin users recruited originally in prisons in New South Wales, Australia. Data were linked for the period 1 June 1997-31 December 2006. Re-incarceration was examined using recurrent-event survival analysis models. Model 1 examined the effect of OST status at release from prison (i.e. in treatment versus out of treatment on the day of release) on re-incarceration. Model 2 considered the effect of remaining in OST after release on risk of re-incarceration.

FINDINGS

Ninety per cent of participants were re-incarcerated following their first observed release. Pre-incarceration cocaine use was associated with a 13% increase in the average risk of re-incarceration. There was no significant association between simply being in OST at the time of release and risk of re-incarceration; however, in the model taking into account post-release retention in treatment, the average risk of re-incarceration was reduced by 20% while participants were in treatment.

CONCLUSIONS

In New South Wales, Australia, opioid substitution treatment after release from prison has reduced the average risk of re-incarceration by one-fifth.

Crack cocaine use in Barcelona: a reason of worry

In Spain, crack cocaine use is silently increasing. In Barcelona, an intentional sample was selected to describe the general characteristics of this consumption. Participants were submitted to an interview and data were analyzed through qualitative research procedures. Users are young males and of low socioeconomic status and formal education. The major pattern of use is compulsive. Illegal income activities are the choice for crack cocaine or money acquisition, increasing individual and social health costs. Polydrug use is a matter of concern. Although these findings can not be generalized, they should be considered for the development of public policies to adequately address crack cocaine users' needs.

Composition, purity and perceived quality of street cocaine in France

BACKGROUND

There is little knowledge about the composition and cocaine content of street cocaine, nor about what users know about it.

METHOD

373 cocaine users were face to face interviewed between May and December 2006 about the last sample of cocaine they had consumed and residual amounts of the substances actually used were analysed using gas phase chromatography coupled to mass spectrometry (GC-MS). Users rated the perceived quality of their product ("good", "average", "poor"), its "estimated percentage of cocaine" and any cutting agents it contained. Price, quantity, place of purchase (street, dealer's premise, appointment), mode of administration (sniffing, injection, smoking) and the supposed nature of the sample (natural, synthetic, no distinction ever made) were also reported. Perceived quality was modelled using multivariate multinomial regression.

RESULTS

The median cocaine content was 22%. Altogether, 343 samples contained cocaine, among which 75% contained at least one adulterant. The most frequently occurring were phenacetin (54% of the samples), caffeine (17%), paracetamol (14%), diltiazem and lidocaïne (11%). Users showed relatively poor discrimination concerning cocaine purity, and only 12% reported at least one of the detected adulterants. The major determinants of their perception of cocaine quality were: place of purchase, natural origin, price per gram, actual cocaine content and mode of administration.

CONCLUSION

The composition of street cocaine is largely unknown to users. Users' perceptions of cocaine quality are based partly on false beliefs and certain administration modes. This may contribute to favouring very risky practices. The effects of adulterants on users' health should be investigated.

Contemporary cocaine use patterns and associated harms in Melbourne and Sydney, Australia

The aim of this paper was to explore the nature of cocaine use and harms through a cross-sectional survey of cocaine users interviewed in the two largest Australian cities of Sydney (n = 88) and Melbourne (n = 77) between October 2004 and January 2005. The study supported previous findings that Australian cocaine users could be classified broadly into two types. The majority of cocaine users interviewed were classified as socially and economically integrated. They were young, employed, well-educated people who generally snorted cocaine on a recreational basis, typically in conjunction with other illicit and licit drugs. A second group of socially and economically marginalised users, residing mainly in Sydney, injected cocaine often in conjunction with heroin. This group reported significantly higher levels of cocaine use, cocaine dependence, criminal behaviour and human immunodeficiency virus (HIV) risk-taking behaviour. Heroin use was found to predict independently higher levels of cocaine use, criminal behaviour, needle sharing and physical problems in this sample, suggesting that increased resources and coverage for combined heroin/cocaine users may have scope for reducing cocaine-related problems in the Australian community.

The association between cocaine use and short-term outcomes for the treatment of heroin dependence: findings from the Australian Treatment Outcome Study (ATOS)

The aim of this study was to determine the prevalence of cocaine use among individuals presenting for treatment for heroin dependence, describe the clinical profile of heroin users who also use cocaine and to establish the effects of cocaine use on short term outcomes for the treatment for heroin dependence. A longitudinal follow-up of 549 heroin users recruited in Sydney for the Australian Treatment Outcome Study was conducted at 3-month post-baseline interview. At baseline, current cocaine use was common (39%) and was associated with increased drug use, needle risk taking and criminality. The 3-month prevalence of cocaine use declined significantly to 19%. Thirty-five per cent of those who had used cocaine at baseline continued to use at 3 months, while 9% of the sample had commenced cocaine use. Those who entered residential rehabilitation at baseline were less likely than other treatment entrants and the non-treatment group to have used cocaine at follow-up. Treatment retention was not affected by baseline cocaine use status; however, baseline cocaine users (CU) displayed higher levels of heroin use, polydrug use and drug-related problems. A poorer outcome was associated with the commencement or continuation of cocaine use, while cessation of cocaine use resulted in significant improvements on these measures. Cocaine use was common among individuals seeking treatment for heroin dependence and was an important moderator of treatment outcome. It appears that cocaine use has a strong negative effect on treatment outcome over and above that caused by polydrug use generally.

Among long-term crack smokers, who avoids and who succumbs to cocaine addiction?

Crack cocaine is a highly addictive drug. To learn more about crack addiction, long-term crack smokers who had never met the DSM-IV criteria for lifetime cocaine dependence were compared with those who had. The study sample consisted of crack users (n=172) from the Dayton, Ohio, area who were interviewed periodically over 8 years. Data were collected on a range of variables including age of crack initiation, frequency of recent use, and lifetime cocaine dependence. Cocaine dependence was common with 62.8% of the sample having experienced it. There were no statistically significant differences between dependent and non-dependent users for age of crack initiation or frequency of crack use. In terms of sociodemographics, only race/ethnicity was significant, with proportionally fewer African-Americans than whites meeting the criteria for cocaine dependence. Controlling for sociodemographics, partial correlation analysis showed positive, statistically significant relationships between lifetime cocaine dependence and anti-social personality disorder, attention deficit/hyperactivity disorder, and lifetime dependence on alcohol, cannabis, amphetamine, sedative-hypnotics, and opioids. These results highlight the importance addressing race/ethnicity and comorbid disorders when developing, implementing, and evaluating interventions targeting people who use crack cocaine. Additional research is needed to better understand the role of race/ethnicity in the development of cocaine dependence resulting from crack use.

Increasing prevalence of cocaine as the primary detoxification diagnosis among admissions presenting with current intravenous drug use: a review of detoxification records from northern British Columbia, 1999-2005

OBJECTIVES

This study sought to document the trends in drug use among intravenous drug users (IDUs) in northern British Columbia, and to discuss the public health implications.

METHOD

We conducted a 7-year medical-chart review of all IDU-related admissions (n = 2072) to an inpatient alcohol and drug detoxification centre in Prince George, British Columbia. Primary detoxification diagnosis was modeled onto year of admission using generalized estimating equations (GEE).

RESULTS

Our study demonstrated an increasing prevalence of cocaine as the primary detoxification diagnosis in IDU-related admissions in northern BC, from 32% of all IDU admissions in 1999 to 64% in 2001, and then a relatively steady elevated rate of approximately 60% between 2001-2005.

CONCLUSIONS

Given that needle exchange programs and other harm reduction services for IDUs in British Columbia are not readily available in many northern and rural areas, the risks associated with intravenous cocaine use among northern IDUs represent a serious public health challenge. Tailored harm reduction strategies should take into account the prominence of intravenous cocaine use as an HIV risk factor. In areas without well-established intravenous drug use monitoring programs, such as rural and remote areas, detoxification treatment records may serve as important sentinels for changing drug use patterns among IDUs.

The effect of baseline cocaine use on treatment outcomes for heroin dependence over 24 months: Findings from the Australian Treatment Outcome Study

AIMS

The aim of this study was to determine the effects of baseline cocaine use on treatment outcomes for heroin dependence over a 24-month period.

DESIGN

A longitudinal cohort (24 months) study was carried out. Interviews were conducted at baseline, 3, 12, and 24 months.

SETTING

The study setting was Sydney, Australia.

PARTICIPANTS

Six hundred fifteen heroin users were recruited for the Australian Treatment Outcome Study.

FINDINGS

Cocaine use was common at baseline (40%) but decreased significantly over the study period. Even after taking into account age, sex, treatment variables, current heroin use, and baseline polydrug use, baseline cocaine use remained a significant predictor of poorer outcomes across a range of areas. Baseline cocaine users were more likely to report heroin use, unemployment, needle sharing, criminal activity, and incarceration over the 24-month study period.

CONCLUSIONS

Cocaine consumption among heroin users has repercussions across a range of areas that persist far beyond the actual period of use. Consequently, treatment providers should regard cocaine use among clients as an important marker for individuals who are at risk of poorer treatment outcome.

Crack cocaine trajectories among users in a midwestern American city

AIMS

Although crack cocaine first appeared in cities in the United States in the mid-1980s, little is known about its use over long periods of time. This study identified crack cocaine user groups on the basis of long-term trajectories.

DESIGN

Following a natural history approach, data were collected periodically from 1996 to 2005. Group-based modeling assessed the probability of a crack smoker becoming abstinent during the observation period.

SETTING

A targeted sampling plan guided the recruitment of a community sample of crack cocaine users in Dayton, Ohio.

PARTICIPANTS

Crack smokers (n = 430) 18 years or older whose urine tested positive for cocaine metabolites at the baseline interview.

MEASUREMENTS

Interviewer-administered and audio computer self-administered, structured questionnaires were used to collect data on a range of variables, including frequency of crack use. Abstinence was defined as not having used crack for at least 6 consecutive months during the study.

FINDINGS

Three trajectory-based groups were identified: (1) No Change, characterized by a very low probability of abstinence; (2) Some Change, characterized by a low to moderate probability of abstinence; and (3) Dramatic Change, characterized by a high probability of abstinence. African Americans and men were significantly less likely to become abstinent. For the majority of the people (63.6%), crack use was uninterrupted by extended periods of abstinence during the study.

CONCLUSION

Crack cocaine use that persists for a decade or longer may well be the norm for a large proportion of people who have experience with the drug.

New developments in the pharmacotherapy of cocaine abuse

Despite huge advances in the neuroscience of substance abuse and dependence in the past 20 years, no approved pharmacological treatment exists for cocaine abuse. The available drugs for the treatment of cocaine abuse are poorly effective, hence the need for new compounds to be screened and tested for efficacy: targeting symptoms might improve the effectiveness of the treatment of cocaine abuse and dependence. On the basis of the known neurochemistry of cocaine, some target compounds have been studied: among others, BP-897, a D3 partial agonist; vanoxerine, a highly selective inhibitor of dopamine uptake; aripiprazole, a partial mixed-action agonist approved for the treatment of schizophrenia. Recently modafinil, approved for the treatment of narcolepsy, proved effective in favouring cocaine abstinence in cocaine-abusing people. Some placebo-controlled studies also reported the effectiveness of topiramate, a licensed antiepileptic drug, and of tiagabine, a gamma-aminobutyric acid (GABA) re-uptake inhibitor also approved as an anticonvulsant; both compounds increased cocaine abstinence with no serious adverse events. Promising results came from two more compounds acting on the GABA circuits, baclofen and valproic acid. Finally disulfiram, prescribed with active psychosocial therapy, was found to favour higher retention rates and longer abstinence periods from both alcohol and cocaine in polydrug-abusing patients. An alternative approach rests on the use of vaccines, to date in the experimental stage still. Psychosocial treatments are a useful companion in the pharmacotherapy of cocaine abuse, with group therapy and contingency management therapies improving motivation and social functioning, particularly in patients abusing alcohol as well.

Cocaine- and opiate-related fatal overdose in New York City, 1990-2000

Background

In New York City (NYC), the annual mortality rate is higher for accidental drug overdoses than for homicides; cocaine and opiates are the drugs most frequently associated with drug overdose deaths. We assessed trends and correlates of cocaine- and opiate-related overdose deaths in NYC during 1990–2000.

Methods

Data were collected from the NYC Office of the Chief Medical Examiner (OCME) on all fatal drug overdoses involving cocaine and/or opiates that occurred between 1990–2000 (n = 8,774) and classified into three mutually exclusive groups (cocaine only; opiates-only; cocaine and opiates). Risk factors for accidental overdose were examined in the three groups and compared using multinomial logistic regression.

Results

Overall, among decedents ages 15–64, 2,392 (27.3%) were attributed to cocaine only and 2,825 (32.2%) were attributed to opiates-only. During the interval studied, the percentage of drug overdose deaths attributed to cocaine only fell from 29.2% to 23.6% while the percentage of overdose deaths attributed to opiates-only rose from 30.6% to 40.1%. Compared to New Yorkers who fatally overdosed from opiates-only, fatal overdose attributed to cocaine-only was associated with being male (OR = 0.71, 95% CI 0.62–0.82), Black (OR = 4.73, 95% CI 4.08–5.49) or Hispanic (OR = 1.51, 95% CI 1.29–1.76), an overdose outside of a residence or building (OR = 1.34, 95% CI 1.06–1.68), having alcohol detected at autopsy (OR = 0.50, 95% CI 0.44–0.56) and older age (55–64) (OR = 2.53 95% CI 1.70–3.75)).

Conclusion

As interventions to prevent fatal overdose become more targeted and drug specific, understanding the different populations at risk for different drug-related overdoses will become more critical.

Psychosocial approaches to psychostimulant dependence: A systematic review

This review examines the nature and evidence for the effectiveness of psychosocial interventions for psychostimulant dependence. Psychostimulant dependence and related harms continue to increase in many parts of the world, while treatment responses are predominantly limited to psychosocial interventions. The effectiveness of psychosocial interventions is compromised by poor rates of treatment induction and retention. As with other substance use disorders, increasing the diversity of treatment options is likely to improve treatment coverage and outcomes across a broader range of users. Identifying medications that might enhance treatment induction and retention would also enhance the effectiveness of psychosocial programs. It is concluded that psychosocial interventions are moderately effective in reducing psychostimulant use and related harms among psychostimulant-dependent persons.

Comparative cardiac pathology among deaths due to cocaine toxicity, opioid toxicity and non-drug-related causes

AIM

To compare cardiac and cerebrovascular pathology among deaths due to cocaine toxicity, deaths due to opioid toxicity and deaths from hanging that were toxicologically negative for cocaine/opioids.

DESIGN

Case-control.

FINDINGS

The cocaine group had significantly higher proportions of left ventricular hypertrophy and ischaemic heart disease than either comparison group. Coronary artery atherosclerosis was also detected in significantly higher proportions of cocaine cases than in either comparison group. The cocaine group was more likely than either comparison group to have atherosclerosis of the left anterior descending coronary artery, right coronary artery and circumflex artery. Only in the left anterior descending coronary artery did the cocaine group exhibit higher levels of moderate-severe atherosclerosis. Cocaine cases also had significantly higher levels of cerebrovascular atherosclerosis than either comparison group.

CONCLUSIONS

Levels of cardiac and cerebrovascular pathology were higher among cocaine users than either comparison group. The high levels of cardiac and cerebrovascular pathology seen among cocaine cases do not appear to be artefacts of a drug-dependent life-style, but relate specifically to cocaine.

Using intervention time series analyses to assess the effects of imperfectly identifiable natural events: a general method and example

Background

Intervention time series analysis (ITSA) is an important method for analysing the effect of sudden events on time series data. ITSA methods are quasi-experimental in nature and the validity of modelling with these methods depends upon assumptions about the timing of the intervention and the response of the process to it.

Method

This paper describes how to apply ITSA to analyse the impact of unplanned events on time series when the timing of the event is not accurately known, and so the problems of ITSA methods are magnified by uncertainty in the point of onset of the unplanned intervention.

Results

The methods are illustrated using the example of the Australian Heroin Shortage of 2001, which provided an opportunity to study the health and social consequences of an abrupt change in heroin availability in an environment of widespread harm reduction measures.

Conclusion

Application of these methods enables valuable insights about the consequences of unplanned and poorly identified interventions while minimising the risk of spurious results.

The effect of persistence of cocaine use on 12-month outcomes for the treatment of heroin dependence

AIMS

To determine the effects of cocaine use across the study period on outcomes of treatment for heroin dependence 12 months post-treatment entry.

DESIGN

Longitudinal cohort (12 months). Interviews were conducted at baseline, 3 and 12 months.

SETTING

Sydney, Australia.

PARTICIPANTS

Four hundred ninety-five heroin users recruited for the Australian Treatment Outcome Study and re-interviewed at 12-month follow-up.

FINDINGS

Cocaine was widely used among treatment entrants in NSW, with almost all having a lifetime history of cocaine use and almost half having used in the month preceding baseline. While there was an overall decline in cocaine use across the study period, individual use patterns varied widely. Approximately half of the cohort did not report cocaine use at any data point, with the remainder reporting having used at one (29%), two (12%), or at all three (5%) points. Cocaine use across the study period was an independent predictor of most major treatment outcomes, with more cocaine use points predicting poorer outcome. Persistent cocaine use predicted a higher prevalence of homelessness, heroin use, daily injecting, needle sharing and injection-related health problems at 12 months as well as more extensive recent polydrug use.

CONCLUSIONS

Cocaine use was common among individuals seeking treatment for primary heroin dependence in NSW. Any cocaine use over the study period was associated with poorer outcomes in virtually all areas. Persistent cocaine use over the study period, however, appeared particularly detrimental. Cocaine use among clients should evidently be a cause for concern amongst treatment providers and may warrant being specifically targeted during treatment.

Was an increase in cocaine use among injecting drug users in New South Wales, Australia, accompanied by an increase in violent crime?

Background

A sharp reduction in heroin supply in Australia in 2001 was followed by a large but transient increase in cocaine use among injecting drug users (IDU) in Sydney. This paper assesses whether the increase in cocaine use among IDU was accompanied by increased rates of violent crime as occurred in the United States in the 1980s. Specifically, the paper aims to examine the impact of increased cocaine use among Sydney IDU upon police incidents of robbery with a weapon, assault and homicide.

Methods

Data on cocaine use among IDU was obtained from the Illicit Drug Reporting System (IDRS). Monthly NSW Police incident data on arrests for cocaine possession/use, robbery offences, homicides, and assaults, were obtained from the Bureau of Crime Statistics and Research. Time series analysis was conducted on the police data series where possible. Semi-structured interviews were conducted with representatives from law enforcement and health agencies about the impacts of cocaine use on crime and policing.

Results

There was a significant increase in cocaine use and cocaine possession offences in the months immediately following the reduction in heroin supply. There was also a significant increase in incidents of robbery where weapons were involved. There were no increases in offences involving firearms, homicides or reported assaults.

Conclusion

The increased use of cocaine among injecting drug users following the heroin shortage led to increases in violent crime. Other States and territories that also experienced a heroin shortage but did not show any increases in cocaine use did not report any increase in violent crimes. The violent crimes committed did not involve guns, most likely because of its stringent gun laws, in contrast to the experience of American cities that have experienced high rates of cocaine use and violent crime.

Underlying causes of cocaine, amphetamine and opioid related deaths in Australia

OBJECTIVE

To examine the characteristics of deaths in Australia where opioids, cocaine or amphetamines were mentioned, taking into account changes in the use and availability of these drugs in recent years.

DESIGN

Data were analysed from the Australian Bureau of Statistics and Causes of Death dataset between 1997 and 2002 on all deaths in which cocaine, amphetamines or opioids were mentioned including deaths where (a) the drugs were considered an underlying cause of death, (b) the drugs contributed to accidental drug-induced death, and (c) deaths primarily due to other causes. Data from the Australian National Drug Strategy Household Survey were also used to examine the prevalence of use of amphetamines, cocaine and opioids in Australia.

RESULTS

Thirteen deaths were attributed primarily to cocaine, 68 to amphetamines, and 4591 to opioids. An increase occurred in mentions of amphetamines, but half of these were primarily attributed to opioids. Opioid related deaths declined dramatically in 2001, consistent with a marked reduction in availability of heroin in Australia. Cocaine mentions remained relatively stable, with most cases primarily attributed to opioids. Of the other underlying causes of death, suicide was the most prevalent underlying factor, particularly for amphetamine and opioid related deaths.

CONCLUSIONS

Compared with opioid-related deaths, there are small numbers of deaths related to psychostimulants in Australia. Accidental drug induced deaths account for the majority of deaths in which these drugs are mentioned, although minorities of drug related deaths are attributed to suicide.

Cocaine-related fatalities in New South Wales, Australia 1993-2002

AIM

To ascertain the demographic characteristics, circumstances of death, toxicological results, and major autopsy findings of cocaine-related fatalities.

DESIGN

Inspection of the coronial records of all cocaine-related deaths that occurred in New South Wales, Australia between 1 January 1993 and 31 December 2002.

SETTING

New South Wales, Australia.

FINDINGS

146 cases were identified. Cocaine was implicated in the direct cause of death in 86% of cases, an antecedent cause in 8% and a significant condition contributing to death in 7%. The mean age of decedents was 34.1 years, and 84% were male. Half were employed, and 26% were in professional employment. The predominant route of administration was injection (86%), however nasal (8%), oral (3%), smoking (1%), and anal (1%) administration were all recorded. The most common location of death was a private home (53%). No intervention occurred prior to death in 82% of cases. The median blood benzoylecgonine concentration was 0.40 mg/L (range 0.00-20.00 mg/L). Cases had a mean of 3.5 drugs, with morphine (79%) the most common co-occurring drug. In 5% of cases cocaine was the sole drug detected. Cardiac pathology was noted in 57% of cases, most commonly coronary artery atherosclerosis (39%) and cardiac hypertrophy (14%). In 15% of cases moderate to severe arterial occlusion was noted. Cerebrovascular pathology was noted in 22% of cases, most commonly cerebrovascular atherosclerosis (10%).

CONCLUSIONS

Cocaine-related deaths are a significant clinical problem in New South Wales.

Non-fatal cocaine overdose among injecting and non-injecting cocaine users in Sydney, Australia

AIM

To investigate the frequency of non-fatal cocaine overdose, and responses to overdoses, among injecting and non-injecting cocaine users.

DESIGN

Cross-sectional study.

SETTING

Sydney, Australia.

PARTICIPANTS

Two hundred current cocaine users.

MEASUREMENTS

Structured interview.

FINDINGS

Thirteen per cent of the sample had overdosed on cocaine, 7% in the preceding 12 months. Cocaine injectors were more likely to have overdosed, both ever (17 v 6%) and in the preceding 12 months (9 v 3%). The most common symptoms of overdose were palpitations (68%), intense sweating (44%) and seizures (40%). The use of other drugs in combination with cocaine prior to the most recent overdose was prevalent (64%), most commonly opioids (40%), alcohol (24%) and cannabis (24%). Those who had overdosed were more likely to be female, had longer cocaine use careers, had used more cocaine in the preceding month and preceding 6 months, had higher levels of cocaine dependence and more extensive polydrug use. Twenty-four per cent had witnessed a cocaine overdose, 13% in the preceding 12 months. Injectors were more likely to have witnessed overdoses, both ever (35% v 8%) and in the preceding 12 months (20% v 3%).

CONCLUSIONS

Experience of, and exposure to, overdose were not rare events. Cocaine users need to be aware of the possibility and nature of overdose, and that cocaine overdose can occur irrespective of method of use. There is a need to emphasise the potential danger of combining cocaine with other drugs.

Attempted suicide among injecting and noninjecting cocaine users in Sydney, Australia

A sample of 183 current cocaine users, 120 primary injecting cocaine users (ICUs), and 63 primary noninjecting cocaine users (NICUs) were administered a structured interview to ascertain attempted suicide histories, methods used, and factors associated with suicide attempts. All respondents were volunteers and current cocaine users recruited through a wide range of sources. The mean age of participants was 30.1 years, and 65% were male. The ICUs were older (32.3 vs. 26.7 years, respectively), more likely to be male (72% vs. 54%, respectively), to be unemployed (84% vs. 23%, respectively) and to have a prison history (53% vs. 1%, respectively) compared to NICUs. Of the sample, 31% had attempted suicide, 18% had done so on more than one occasion, and 8% had made an attempt in the preceding 12 months. Overall, 28% of the sample had been treated by a medical practitioner after an attempt. ICUs (38%) were significantly more likely than NICUs (10%) to have attempted suicide and to have done so on more than one occasion (23% vs. 3%, respectively). The most common method used among both groups was self-poisoning (ICUs 28%, NICUs 8%), primarily by drug overdose. Violent methods had been used by 22% of ICUs and 3% of NICUs. Multivariate analyses revealed that injecting, female gender, and more extensive polydrug use were independent predictors of a suicide attempt. The prevalence of suicide in this study indicates that it represents a major clinical issue among ICUs and to a lesser extent among noninjectors of the drug. Those treating cocaine users for drug dependence need to be aware of the salience of suicide as a problem, among injectors in particular.

Adapting the Illicit Drug Reporting System (IDRS) to examine the feasibility of monitoring trends in the markets for 'party drugs'

Since 1996, the Illicit Drug Reporting System (IDRS), Australia's strategic early warning system for illicit drug trends, has monitored annual trends in the markets for the four main illicit drug classes, cannabis, methamphetamine, cocaine and heroin. In 2000, a 2-year trial was implemented to examine the feasibility of using similar methodology to monitor trends in the markets for 'party drugs'. A triangulation of three data sources was sought: (1) quantitative interviews with a 'sentinel' population of drug users; (2) qualitative interviews with key informants (KIs), or those who have contact with drug users through their work; (3) extant indicator data sources such as the purity of illicit drugs seized by law enforcement agencies. The results suggested that the feasibility of collecting detailed, reliable and valid data about party drug markets is a direct function of the size of those markets. The trial demonstrated that the system would allow the successful monitoring of markets for party drugs that are relatively widely used, such as ecstasy, but would be less sensitive in monitoring markets for party drugs that are used by small proportions of the total population, such as gamma-hydroxy-butyrate (GHB) and ketamine. Methodological issues encountered during the conduct of this trial are discussed, including defining the appropriate sentinel population of drug users, identifying relevant key informants, and the relative absence of extant indicator data sources that could inform our understanding of party drug markets.

Le « partage » des matériels d’injection chez les jeunes usagers de drogues injectables de Montréal

Cette étude visait à déterminer dans quels contextes les jeunes de la rue qui s’injectent des drogues « partagent » des matériels d’injection. Nous avons mené des entrevues en profondeur auprès de 24 jeunes (15 à 22 ans) recrutés avec l’aide d’organismes communautaires et par la technique de « snowballing ». Au moment de la première injection, ces jeunes sont peu préoccupés par les risques d’infection et s’inquiètent davantage du risque de développer une dépendance. Cependant, ceux qui persistent sont conscients des risques associés au « partage » de seringues et considèrent qu’il s’agit d’une pratique à éviter dans une ville où les programmes de prévention fournissent l’accès gratuit aux seringues. Ce n’est toutefois pas le cas pour les autres matériels d’injection. Les contextes de vulnérabilité par rapport au « partage » se constituent au carrefour de plusieurs facteurs qui sont à la fois d’ordre individuel et social. Certains moments critiques dans la trajectoire de vie des jeunes par rapport à la consommation de drogues et à la vie dans la rue ainsi qu’un degré élevé d’intimité entre partenaires d’injection les fragilisent pour ce qui est des pratiques non sécuritaires.

Pilot randomized double blind placebo-controlled study of dexamphetamine for cocaine dependence

AIMS

To establish the feasibility of conducting a placebo-controlled clinical trial of dexamphetamine replacement therapy for cocaine dependence and to obtain preliminary data.

DESIGN

Double-blind randomized placebo-controlled trial.

PARTICIPANTS

Thirty cocaine-dependent injecting drug users.

INTERVENTION

Subjects were assigned randomly to receive 60 mg/day dexamphetamine (n = 16) or placebo (n = 14) for 14 weeks.

MEASUREMENTS

Immunoassay and mass spectrometric techniques were used to identify cocaine metabolites in urine. Subjects were screened using the Composite International Diagnostic Interview and DSM-IV. The Opiate Treatment Index, Brief Symptom Inventory, Severity of Dependence Scale and visual analogue craving scales were used to collect pre- and post-self-report data.

FINDINGS

Treatment retention was equivalent between groups; however, outcomes favoured the treatment group with no improvements observed in the placebo control group. The proportion of cocaine-positive urine samples detected in the treatment group declined from 94% to 56% compared to no change in the placebo group (79% positive). While the improvements were not significant between groups, within-group analysis revealed that the treatment group reduced self-reported cocaine use (P = 0.02), reduced criminal activity (P = 0.04), reduced cravings (P < 0.01) and reduced severity of cocaine dependence (P < 0.01) with no within-group improvements found in the placebo group.

CONCLUSIONS

A definitive evaluation of the utility of dexamphetamine in the management of cocaine dependence is feasible and warranted.

Changes in patterns of drug injection concurrent with a sustained reduction in the availability of heroin in Australia

Between 1996 and 2000, heroin was the drug most frequently injected in Australia, and viable heroin markets existed in six of Australia's eight jurisdictions. In 2001, there was a dramatic and sustained reduction in the availability of heroin that was accompanied by a substantial increase in its price, and a 14% decline in the average purity of seizures analysed by forensic laboratories. The shortage of heroin constitutes a unique natural experiment within which to examine the impact of supply reduction. This paper reviews one important correlate of the shortage, namely changes in patterns of illicit drug injection. A number of studies have consistently suggested that between 2000 and 2001, there was a sizeable decrease in both prevalence and frequency of heroin injection among injecting drug users. These changes were accompanied by increased prevalence and frequency of stimulant injection. Cocaine was favoured in NSW, the sole jurisdiction in which a cocaine market was established prior to the heroin shortage; whereas methamphetamine predominated in other jurisdictions. Some data suggest that, at least in the short-term, some drug injectors left the market altogether subsequent to the reduced heroin availability. However, the findings that (1) some former heroin users switched their drug preference to a stimulant; and (2) subsequently attributed this change to the reduced availability of heroin, suggests that reducing the supply of one drug may serve to increase the use of others. Given the differential harms associated with the use of stimulants and opiates, this possibility has grave implications for Australia, where the intervention and treatment system is designed primarily to accommodate opiate use and dependence.

The monitoring of drug trends in Australia

Recently, there has been increased recognition of the importance of drug information systems (DIS), highlighting the need for an internationally coordinated approach to data collection and advocating the regular assessment of a range of areas. Accurate information provides policy makers with the evidence to evaluate current strategies and to plan future strategies. An effective drug information system (DIS) must collect comprehensive, detailed and in-depth data, while also being sensitive to emergent trends and placing these changes into the context of longer-term trends. An integrated and comprehensive system combines both sensitive (or lead) and slower but more reliable lag indicators. This article reviews conceptual frameworks for DIS and developments in international systems. It then considers the range of DIS in Australia and then describes two integrated monitoring systems with an early warning function: the Illicit Drug Reporting System (IDRS) and the Drug Use Monitoring Australia (DUMA) Programme. Both systems collate sensitive lead indicators, and provide timely information about emerging drug trends in Australia. Together, these two systems are best-placed to provide effective early warning of new trends in illicit drug markets, and constitute an important component of the overall approach to the monitoring of drug use and associated harms in Australia.

Narcotics at street level in Denmark. A prospective investigation from 1995 to 2000

This article describes an investigation of illicit drugs at street level in six selected police districts in different regions of Denmark. The investigation was carried out during a 6-year period from 1995 to 2000. During the period, a total of 1244 samples were examined, as about 200 samples were seized each year. A total of 94% of the seized samples were familiar drugs: heroin base, heroin hydrochloride, cocaine hydrochloride and amphetamine sulphate. Only 2% of the samples contained designer drugs. From having constituted 53% of the samples in 1995, the frequency of heroin base fell during the period to 27% of the samples in 2000. The frequency of heroin hydrochloride was unchanged. In the same period, the frequency of cocaine hydrochloride increased from 10% of the samples in 1995 to about 25% of the samples in 2000. Apart from a few exceptions, cocaine had the same extension in all regions of Denmark after 1996. Amphetamine was more frequent in the west of Denmark, while heroin hydrochloride was more frequent in central Denmark. The purity of heroin base was lower in the period 1997-1999 than in the other years. During the entire period, the purity of cocaine hydrochloride and amphetamine sulphate fell, while the purity of heroin hydrochloride was unchanged. No significant differences between the various regions of Denmark were detected during the period in the purity of heroin hydrochloride, heroin base, cocaine hydrochloride or amphetamine sulphate. MDMA was the most frequent designer drug, but other types of designer drugs such as MDA and MDE and the less common PMA, PMMA and MBDB were also found.