Trends of heroin use and heroin injection epidemics in Europe: Findings from the EMCDDA treatment demand indicator (TDI)

Impaired vision in children prenatally exposed to methadone: an observational cohort study

BACKGROUND/OBJECTIVES

To examine prevalence of failed visual assessment at 8-10 years in children born to methadone-maintained opioid dependent (MMOD) mothers and relate this to known in utero substance exposure.

SUBJECTS/METHODS

Follow up of observational cohort study of methadone-exposed and comparison children matched for birthweight, gestation and postcode of residence at birth. Participants were 144 children (98 exposed, 46 comparison). Prenatal drug exposure was previously established via comprehensive maternal and neonatal toxicology. Children were invited to attend for visual assessment and casenotes were reviewed. Presence of acuity poorer than 0.2 logMAR, strabismus, nystagmus and/or impaired stereovision constituted a 'fail'. Fail rates were compared between methadone-exposed and comparison children after adjusting for known confounding variables.

RESULTS

33 children attended in person: data were also derived from casenote review for all children. After controlling for maternal reported tobacco use, methadone-exposed children were more likely to have a visual 'fail' outcome, adjusted odds ratio 2.6, 95% CI 1.1-6.2; adjusted relative risk 1.8 (95% CI 1.1-3.4). Visual 'fail' outcome rates did not differ between methadone-exposed children who had (n = 47) or had not (n = 51) received pharmacological treatment for neonatal abstinence/opioid withdrawal syndrome (NAS/NOWS); fail rate 62% vs 53% (95% CI of difference-11-27%).

CONCLUSIONS

Children born to MMOD mothers are almost twice as likely as unexposed peers to have significant visual abnormalities at primary school age. Prenatal methadone exposure should be considered in the differential diagnosis of nystagmus. Findings support visual assessment prior to school entry for children with any history of prenatal opioid exposure.

TRIAL REGISTRATION

The study was prospectively registered on ClinicalTrials.gov (NCT03603301), https://clinicaltrials.gov/ct2/show/NCT03603301 .

Estimating the Prevalence of Recreational Opioid Use in Spain Using a Multiplier Method

Acknowledgement of the prevalence of recreational opioid use (PROU) is key to the planning and evaluation of care services. However, in Spain, the prevalence of PROU in recent years is unknown. The objective of this study was to estimate the PROU between 2005 and 2019 in the general populations of six Spanish cities. A benchmark-multiplier methodology was used to estimate the PROU population size. The benchmark used was overdose deaths from recreational opioid use in Spain’s six most populated cities. The multiplier was the overdose death rate in a cohort of heroin users. Linear regression was used to estimate the trend of the PROU estimate over the set period of years. In 2005, the PROU was 4.78 (95%CI 3.16–7.91) per 1000 people. The estimated trend decreased, with the two lowest values being 2.35 per 1000 in 2015 and 2.29 in 2018. In 2019 the PROU was 2.60 per 1000 (95%CI 1.72–4.31), 45% lower than in 2005. While the decline in the PROU continues, its deceleration over the last four years calls for increased vigilance, especially in light of the opioid crisis in North America that has occurred over the last few years.

Cocaine treatment demands in 10 western European countries: observed trends between 2011 and 2018

AIMS

To describe cocaine treatment demand in 10 western European countries and to examine the size, direction and temporality of recent trends in the proportion of cocaine users among all clients entering treatment.

DESIGN

Aggregated data collected through the European Union standardized treatment demand monitoring system (TDI) between 2011 and 2018 were used.

SETTING

Belgium, England, France, Germany, Ireland, Italy, Luxembourg, Spain, Switzerland and the Netherlands.

PARTICIPANTS

In total, more than 700 000 cocaine treatment records were analysed. Clients in treatment for cocaine as primary drug were predominantly male (85%), with an average age of 35 years.

MEASUREMENTS

Number of treatment episodes for substance use and for cocaine as primary or secondary drug were collected year- and country-wise. When available, powder cocaine and crack and patients with and without previous treatment were differentiated.

FINDINGS

Among the participating countries the share of cocaine as primary drug in treatment demand ranged between 4.7% [95% confidence interval (CI) = 4.6-4.9%] in Germany and 43.1% in Spain (95% CI = 42.6-43.5%). The general trend analysis showed a decreasing proportion of cocaine-related treatment entrants between 2011 and 2014 among all subgroups followed by a strong increase in 2015. The increase appeared stronger than for powder cocaine. Seven of 10 countries observed a recent significant increase in the proportion of treatment entrants reporting cocaine as the primary substance: Belgium [annual percentage change (APC) = 9.6%, P < 0.01], England (APC = 14.9%, P < 0.05), France (APC = 21.8%, P < 0.01), Ireland (APC = 28.2%, P < 0.01), Italy (APC = 7.8%, P < 0.01), Spain (APC = 7.0%, P < 0.05) and Switzerland (APC = 12.0%, P < 0.05). Trends were similar when looking at cocaine reported as primary or adjunctive substance.

CONCLUSIONS

Despite substantial country-specific variation regarding cocaine prevalence and treatment demand, there has been an overall significant increase since 2015 in the share of cocaine-related treatment demand in western Europe.

Risk perception, changing social context, and norms prevent transition to regular injection among people who smoke heroin

BACKGROUND

There is a lack of research examining what prevents people who smoke heroin from transitioning to regular injection. This qualitative study aims to improve understanding of environmental influences preventing people who smoke heroin from transitioning to regular injection.

METHODS

In-depth, semi-structured interviews (n = 15) were conducted with people who currently smoked heroin but never injected (n = 10) and those who injected on a few occasions but did not transition to regular injection (n = 5) in Northern Ireland. Multiple recruitment strategies were utilized to generate a community-based sample. Interviews were thematically analysed.

MAIN FINDINGS

Participants identified two main, interconnected influences preventing transition to injecting heroin. Firstly, resistance towards injecting was rooted in micro level perceptions of risks primarily arising from meso level social interactions with people who inject drugs and, to a lesser extent, harm reduction agencies. Secondly, participants identified meso and macro environments defined as changing social contexts and normative beliefs surrounding the acceptability of injecting within their drug-using social networks, facilitated by expanding heron markets, negative interactions with people who inject drugs and new groups of people choosing to smoke heroin due to perceptions of injection risks.

CONCLUSIONS

Findings illuminate environmental influences surrounding and shaping drug consumption practices. Harm reduction strategies should develop and implement safer smoking rooms, community and peer interventions, and improve accessibility to opioid substitution therapy and low threshold outreach services to prevent transitioning to regular heroin injecting.

Mobile Peer-Support for Opioid Use Disorders: Refinement of an Innovative Machine Learning Tool

Background:

The majority of individuals with Opioid Use Disorder (OUD) do not receive any formal substance use treatment. Due to limited engagement and access to traditional treatment, there is increasing evidence that patients with OUDs turn to online social platforms to access peer support and obtain health-related information about addiction and recovery. Interacting with peers before and during recovery is a key component of many evidence-based addiction recovery programs, and may improve self-efficacy and treatment engagement as well as reduce relapse. Commonly-used online social platforms are limited in utility and scalability as an adjunct to addiction treatment; lack effective content moderation (e.g., misinformed advice, maliciousness or “trolling”); and lack common security and ethical safeguards inherent to clinical care.

Methods:

This present study will develop a novel, artificial-intelligence (AI) enabled, mobile treatment delivery method that fulfills the need for a robust, secure, technology-based peer support platform to support patients with OUD. Forty adults receiving outpatient buprenorphine treatment for OUD will be asked to pilot a smartphone-based mobile peer support application, the “Marigold App”, for a duration of six weeks. The program will use (1) a prospective cohort study to obtain text message content and feasibility metrics, and (2) qualitative interviews to evaluate usability and acceptability of the mobile platform.

Anticipated findings and future directions:

The Marigold mobile platform will allow patients to access a tailored chat support group 24/7 as a complement to different forms of clinical OUD treatment. Marigold can keep groups safe and constructive by augmenting chats with AI tools capable of understanding the emotional sentiment in messages, automatically “flagging” critical or clinically relevant content. This project will demonstrate the robustness of these AI tools by adapting them to catch OUD-specific “flags” in peer messages while also examining the adoptability of the platform itself within OUD patients.

Sociocultural aspects of drug dependency during early pregnancy and considerations for screening: Case studies of social networks and structural violence

OBJECTIVE

To contribute in closing the current gap in literature that holistically examines sociocultural influences on perinatal drug dependency. This article draws from social network theory and structural violence to qualitatively consider the contextual components of addiction and substance use during pregnancy, which purposefully moves away from situating this issue from solely being within the contexts of pathologized disorders or products of social inequalities.

DESIGN

Face-to-face semi-structured interviews with drug-dependent pregnant women identified during a reproductive environmental health consultation.

SETTING

Interviews were conducted at a university hospital in southeastern Spain between October 2015 and June 2016.

PARTICIPANTS

10 pregnant women with confirmed perinatal substance use and/or drug dependency.

FINDINGS

The sociocultural perspective offers a useful lens by which providers can understand the reasons for initial substance use and progress of multi-drug dependency as way of individually tailoring intervention strategies for expecting mothers. This perspective draws from the frameworks of social network analysis (SNA) and structural violence to dialectically examine drug dependency in this unique patient population not to be solely an individual occurrence, but rather a combination of macro and micro-level factors at play.

KEY CONCLUSIONS

The sociocultural approach in examining maternal health allows for the holistic exploration of the already taboo and symbolically paradoxical phenomenon of drug dependency in pregnant women.

IMPLICATIONS FOR PRACTICE

The "Hoja Verde" and similar perinatal screening methods that comprehensively assess for the potential of environmental risks can be a key instrument in the practice of preventing developmental issues of children as early as pregnancy and into adolescence.

Rising incidence of ageing opioid users within the EU wide treatment demand indicator; The Irish opioid epidemic from 1996 to 2014

BACKGROUND

Literature identifies older people who use opioids as a neglected population. Little is known about temporal changes, or about treatment demand among this population.

METHODS

The EU Treatment Demand Indicator (TDI) for Ireland (1996-2014) was analyzed for trends in new opioid treatment admissions, ageing and drug using behaviors. A Joinpoint analysis was conducted.

RESULTS

Data from 18,692 individuals entering treatment for the first time showed that while the trend of age-adjusted incidence declined between 1996 and 2014, incidence among older age groups increased, with a rising incidence not previously observed among those aged 50 years and older. Subgroups of early and late treatment entries, and early and late opioid onset were observed. The median age commencing opioid use increased by three years from 18 to 21 years (U = 326141.5, p < 0.001). The median age entering treatment increased by 11 years (from age 20 to age 31) (U = 145465.5, p < 0.001). The median opioid-using duration prior to treatment increased by 5 years (from 2 to 7 years) (U = 170807.5, p < 0.001). Half of the individuals started injecting within one year of first using opioids. The median time between first injecting and commencing treatment increased by 6 years for men and 2 years for women.

CONCLUSIONS

The study utilizes European TDI data and finds that those entering treatment in Ireland is older, are injecting longer and are taking longer to enter treatment. These findings highlight how TDI data can be used to identify hidden groups at risk of chronic harm which may require prioritizing in policy and practice.

Cost-Effectiveness of Take-Home Naloxone for the Prevention of Overdose Fatalities among Heroin Users in the United Kingdom

BACKGROUND

Heroin overdose is a major cause of premature death. Naloxone is an opioid antagonist that is effective for the reversal of heroin overdose in emergency situations and can be used by nonmedical responders.

OBJECTIVE

Our aim was to assess the cost-effectiveness of distributing naloxone to adults at risk of heroin overdose for use by nonmedical responders compared with no naloxone distribution in a European healthcare setting (United Kingdom).

METHODS

A Markov model with an integrated decision tree was developed based on an existing model, using UK data where available. We evaluated an intramuscular naloxone distribution reaching 30% of heroin users. Costs and effects were evaluated over a lifetime and discounted at 3.5%. The results were assessed using deterministic and probabilistic sensitivity analyses.

RESULTS

The model estimated that distribution of intramuscular naloxone, would decrease overdose deaths by around 6.6%. In a population of 200,000 heroin users this equates to the prevention of 2,500 premature deaths at an incremental cost per quality-adjusted life year (QALY) gained of £899. The sensitivity analyses confirmed the robustness of the results.

CONCLUSIONS

Our evaluation suggests that the distribution of take-home naloxone decreased overdose deaths by around 6.6% and was cost-effective with an incremental cost per QALY gained well below a £20,000 willingness-to-pay threshold set by UK decision-makers. The model code has been made available to aid future research. Further study is warranted on the impact of different formulations of naloxone on cost-effectiveness and the impact take-home naloxone has on the wider society.

Treatment for opioid use and outcomes in older adults: a systematic literature review

BACKGROUND

Historically, issues relating to problem substance use among older people have received little attention, and have only recently been recognised.

METHODS

A literature review of relevant material was conducted in November 2015 to assess current outcome research among older adults treated for opioid dependence. Multiple electronic databases were searched and results were supplemented by grey literature, library and online searches, and relevant references within selected articles. Retrieved articles were assessed for relevance against the inclusion and exclusion criteria. Results were reviewed to identify major findings and recommendations.

RESULTS

A total of 76 titles were included in the review. Most research conducted on older adults involves alcohol and prescription medications. Older drug users are growing in number and have a unique profile, with many presenting for treatment for the first time aged 50-70 years. Findings reveal (1) opioid treatment numbers are decreasing, however the average age of treatment admissions is increasing, (2) there is no consensus on what old is (3) two distinct types of older opioid substance users exist (early/late onset), (4) older clients achieve better treatment outcomes than younger counterparts, and (5) older women achieve better treatment outcomes than men.

CONCLUSIONS

Findings suggest that little is known about treatment outcomes among older people. Problematic drug use (of which opioids make up the largest proportion) had been incorrectly assumed to end as patients age. Defining an age limit for 'older' is important. Addiction and healthcare services must anticipate and prepare for increased demand by this group.

Effect of ageing and time since first heroin and cocaine use on mortality from external and natural causes in a Spanish cohort of drug users

BACKGROUND

We aimed to assess the effect of ageing and time since first heroin/cocaine use on cause-specific mortality risk and age disparities in excess mortality among heroin (HUs) and cocaine users (CUs) in Spain.

METHODS

A cohort of 15,305 HUs and 11,905 CUs aged 15-49 starting drug treatment during 1997-2007 in Madrid and Barcelona was followed until December 2008. Effects of ageing and time since first heroin/cocaine use were estimated using a competing risk Cox model and the relative and absolute excess mortality compared to the general population through directly age-sex standardized rate ratios (SRRs) and differences (SRDs), respectively.

RESULTS

Mortality risk from natural causes increased with time since first heroin use, whereas that from overdose declined after having peaked in the first quinquennium. Significant effects of time since first cocaine use were not identified, although fatal overdose risk seemed higher in CUs after five years. Mortality risk from natural causes (HUs and CUs), injuries (HUs), and overdoses (CUs) increased with age, the latter without reaching statistical significance. Crude mortality rates from overdoses and injuries remained very high at age 40-59 among both HUs (595 and 217 deaths/100,000 person-years, respectively) and CUs (191 and 88 deaths/100,000 person-years). SRDs from all and natural causes were much higher at age 40-59 than 15-29 in both HUs (2134 vs. 834 deaths/100,000 person-years) and CUs (927 vs. 221 deaths/100,000 person-years), while the opposite occurred with SRRs.

CONCLUSION

The high mortality risk among HUs and CUs at all ages from both external and natural causes, and increased SRDs with ageing, suggest that high-level healthcare and harm reduction services should be established early and maintained throughout the lifetime of these populations.

Cannabis Use among People Entering Drug Treatment in Europe: A Growing Phenomenon?

This paper explores European and national trends in specialised drug treatment entry for cannabis-related problems. The analysis is based on data for the years 2003-2014 from 22 European countries. Between 2003 and 2014, the overall number and proportion of primary cannabis-related first-time entrants increased significantly. A joinpoint regression analysis indicates that the overall increase of cannabis treatment entries is continuous, although country-related differences are observed. Possible explanations for the increase and different time trends are discussed including an increase in cannabis prevalence and cannabis-related problems, changes in risk perception, increases in cannabis potency, changes in referral practices and increased availability and accessibility of treatment services.

Anxiety disorders are associated with early onset of heroin use and rapid transition to dependence in methadone maintained patients

Early onset of heroin use is a severity marker of heroin use disorder. We studied the interaction between early onset and rapid transition to heroin dependence recorded with retrospective interviews in 213 patients with severe heroin dependence and history of methadone maintenance treatment. General linear models were used to identify independent factors associated with early onset, factors associated with rapid transition to dependence, and a multivariate model was used to study the interaction of those two dimensions. Lifetime history of anxiety disorders and age at onset of cannabis use are shared common risk factors and are associated with the interaction.

Correlates of injection drug use among individuals admitted to public and private drug treatment facilities in Turkey

BACKGROUND

The number of individuals seeking treatment for drug use has been increasing in recent years in Turkey. However, existing research on patterns and risk factors for drug use and how they vary by age and location in Turkey is limited.

METHODS

We examined the socio-demographic characteristics, drug use behaviors, and treatment history of citizens admitted to inpatient substance use treatment at public and private facilities in Turkey during 2012 and 2013 and identified correlates of lifetime and current injection drug use.

RESULTS

Of the 11,247 patients at the 22 public treatment centers in 2012-2013, a majority were male, lived with family, were unemployed, and had an average age of 27 years. Within private clinics (n=663), a higher proportion was female (9.7% private vs. 5.7% public), aged 11-17 years old (13% vs. 7.4%), used cannabis as their primary drug (18.4% vs. 13.2%), and had previously received drug treatment (57% vs. 47.2%). Within public centers, 40.4% reported ever injecting drugs and 33.7% reported injecting in the past 30 days; the corresponding percentages at private clinics were 22.5% and 18.1%. Significant predictors of injection drug use included being homeless, being a temporal employee or unemployed, having higher education, heroin as a preferred drug, having a longer duration of drug use, and prior drug treatment.

CONCLUSION

Prevention and intervention efforts are needed to reduce the transition to heroin and injection drug use among youth as well as improve access to a variety of drug treatment options for people who use substances in Turkey.

Treatment for substance use disorders: the Belgian Treatment Demand Indicator registration protocol

BACKGROUND

Registration of patients with substance use disorders is of key importance to get insights and to study trends in patients characteristics and substance use patterns. The Treatment Demand Indicator (TDI) is gathering this information at European level since 2000. In Belgium, this registration started at national level in 2011 and an increasing number of facilities of different types are participating in this data collection since then.

METHODS/DESIGN

This surveillance register collects information on every treatment episode started by patients for their substance use disorder. Information is collected on socio-demographic characteristics of the patient, treatment history and substance use patterns. Patients are identified uniquely using their national identification number in order identify multiple episodes followed by a same person. A large range of treatment facilities have the possibility to participate in this registration to allow a wide coverage of the population.

DISCUSSION

The objective of the paper is to facilitate the use of data by authorities or researchers by correctly describing all aspects of the indicator. The case definition, the variables collected and the way data should be reported are of key importance to use and interpret the data correctly. An overview of the data registered in 2014 gives also an idea of the content of the database. The article also pictures the strengths and limitations of the register and foresees some future improvements.

One-Year Follow-Up of Heroin-Dependent Adolescents Treated with Buprenorfine/Naloxone for the First Time in a Substance Treatment Unit

The aims of the present study were to evaluate 1-year retention in program and buprenorphine/naloxone (BUP/NAL) treatment, and abstinence of heroin-dependent adolescents. The present study included the follow-up information of 112 heroin dependent adolescents who took BUP/NAL treatment for the first time in a specific inpatient unit. Retention and abstinence were assessed by self-report and urine drug screen at each visit. Mean age was 16.9 years, with 101 (90.2%) male. Program retention was 81.3% at day 30, and 24.1% at 1 year, while retention in BUP/NAL treatment was 69.6% at day 30 and 16.1% at 1 year. Rates of abstinence were 69.0% at day 30 and 10.3% at 1 year. There was a significant positive correlation between duration of inpatient treatment and program retention, treatment retention, abstinence (p < 0.05 for all), and between the dose and treatment retention, abstinence (p < 0.05 for both). Patients with comorbid psychiatric disease were more likely to be retained in treatment for 3 months, and in program for 6 months (p < 0.05, for all). Patients who completed inpatient treatment were more likely to be retained in treatment for 1 year, and in program for 9 months, and to be abstinent for 1 year (p < 0.05, for all). Findings suggested that starting BUP/NAL treatment in an inpatient unit might result in better outcomes compared to literature. Duration of inpatient treatment, the completion of inpatient treatment, BUP/NAL dose, and having a comorbid psychiatric disease seemed to be important factors for heroin-dependent adolescents in retention and abstinence within 1-year period.

[Use of psychostimulants in a sexual context: Analysis of cases reported to the French network of Addictovigilance Centers]

The "SLAM" phenomenon is an increasingly popular practice, in Paris and London gay scene, defined by 3 characteristics: injection, sexual party and psychostimulant drugs. The French Medical Agency requested a risk assessment of "SLAM" and more broadly of the use of psychostimulants in a sexual context, by the analysis of complications related to this practice notified to the French Network of Addictovigilance Centers. All cases of complications related to "SLAM" practice, including cases of abuse or dependence, and somatic and psychiatric complications, were analysed. Between January 2008 to December 2013, 51 cases were collected. Users were exclusively men, with a mean age of 40 years, having psychostimulants exposure in a sexual context, mainly in men who have sex with men (MSM) context (100%, n=35). The prevalence of human immunodeficiency virus (HIV) infection was 82% (n=32) with a high level of HIV/hepatitis C virus (HCV) co-infection (50%, n=16). The main psychostimulants reported are synthetic cathinones (89.5%). Cathinones users tended to be polydrug users: 62% also reported use other than psychoactive substances (gamma-butyrolactone [GBL], ketamine, methylenedioxyméthamphetamine [MDMA], lysergic acid diethylamide [LSD]…). The main complications were psychiatric disorders in 50% (psychotic symptoms, agitation, anxiety, suicidal ideas or attempt and forensic problems), acute intoxication in 25% (including 3 deaths), dependence and abuse in 17% and infectious complications in 8% (viral seroconversion). Health professionals as well as users should be aware of the physical (cardiovascular) and behavioural (psychic, fast dependence syndrome) toxicity of cathinones. Risk reduction policy must be targeted to the population of MSM with specific interventions both on risky sexual behavior and substance use.

Substance use among Dutch homeless people, a follow-up study: prevalence, pattern and housing status

BACKGROUND

Previous studies have shown that substance use among homeless people is a prevalent problem that is associated with longer durations of homelessness. Most studies of substance use among the homeless were carried out outside Europe and have limited generalizability to European countries. This study therefore aimed to address the prevalence of substance use among homeless people in the Netherlands, the pattern of their use and the relationship with housing status at follow-up.

METHODS

This study included 344 participants (67.1% of the initial cohort) who were followed from baseline to 18 months after the baseline interview. Multinomial logistic regression analyses examined the relationship between substance use and housing status.

RESULTS

The most reported substances which were used among these homeless people were cannabis (43.9%) and alcohol (≥5 units on one occasion) (30.7%). Other substances were used by around 5% or less of the participants. Twenty-seven percent were classified as substance misuser and 20.9% as substance dependent. The odds to be marginally housed (4.14) or institutionalized (2.12) at follow-up compared to being housed of participants who were substance users were significantly higher than those of participants who did not use substances. The odds to be homeless were more than twice as high (2.80) for participants who were substance dependent compared with those who were not.

CONCLUSION

Homeless people who use substances have a more disadvantageous housing situation at follow-up than homeless people who do not use substances. Attention is needed to prevent and reduce long-term homelessness among substance-using homeless people.

Public spending for illegal drug and alcohol treatment in hospitals: an EU cross-country comparison

Background

In view of the current economic crisis and the resulting austerity measures being implemented by governments across Europe, public expenditure for substance abuse treatment has increasingly become a subject of discussion. An EU cross-country comparison would allow an estimation of the total amount of public resources spent on substance abuse treatment, compare various substance abuse treatment funding options, and evaluate the division of expenditures between alcohol and illegal drugs. The purpose of this study is to estimate the public spending of EU countries for alcohol and illegal drug abuse treatment in hospitals.

Methods

Our study uses a uniform methodology in order to enable valid cross-national comparisons. Our data are drawn from the Eurostat database, which provides anno 2010 data on government spending for the treatment of illegal drug and alcohol abuse in 21 EU member states. The cross-country comparison is restricted to hospitals, since data were unavailable for other types of treatment providers. The systematic registration of in- and outpatient data is essential to monitoring public expenditures on substance abuse treatment using international databases.

Results

Total public spending for hospital-based treatment of illegal drug and alcohol abuse in the 21 EU member states studied is estimated to be 7.6 billion euros. Per capita expenditures for treatment of illegal drug abuse vary, ranging from 0.1 euros in Romania to 13 euros in Sweden. For alcohol abuse, that figure varied from 0.9 euros in Bulgaria to 24 euros in Austria. These results confirm other studies indicating that public expenditures for alcohol treatment exceed that for illegal drug treatment.

Conclusions

Multiple factors may influence the number of hospital days for alcohol or illegal substance abuse treatment, and expenditures fluctuate accordingly. In this respect, we found a strong correlation between gross domestic product (GDP) per capita and public expenditures per hospital day. The prevalence of problematic (illegal or legal) drug use in a country did not correlate significantly with the number of hospital days. Other factors must be included in the analysis of public expenditures for the treatment of substance abuse, such as the drug policy in a given country and the social norms regarding alcohol consumption.

Improved benchmark-multiplier method to estimate the prevalence of ever-injecting drug use in Belgium, 2000-10

Background

Accurate estimates of the size of the drug-using populations are essential for evidence-based policy making. However, drug users form a ‘hidden’ population, necessitating the use of indirect methods to estimate population sizes.

Methods

The benchmark-multiplier method was applied to estimate the population size of ever injecting drug users (ever-IDUs), aged 18–64 years, in Belgium using data from the national HIV/AIDS register and from a sero-behavioral study among injecting drug users. However, missing risk factor information and absence of follow-up of the HIV⁺/AIDS^– cases, limits the usefulness of the Belgian HIV/AIDS register as benchmark. To overcome these limitations, statistical corrections were required. In particular, Imputation by Chained Equations was used to correct for the missing risk factor information whereas stochastic mortality modelling was applied to account for the mortality among the HIV⁺/AIDS^– cases. Monte Carlo simulation was used to obtain confidence intervals, properly reflecting the uncertainty due to random error as well as the uncertainty associated with the two statistical corrections mentioned above.

Results

In 2010, the prevalence (/1000) of ever-IDUs was estimated to be 3.5 with 95% confidence interval [2.5;4.8]. No significant time trends were observed for the period 2000–2010.

Conclusions

To be able to estimate the ever-IDU population size using the Belgian HIV/AIDS register as benchmark, statistical corrections were required without which seriously biased estimates would result. By developing the improved methodology, Belgium is again able to provide ever-IDU population estimates, which are essential to assess the coverage of treatment and to forecast health care needs and costs.