Health trends among drug users attending needle exchange programmes in Switzerland (1994–2000)

The Cumulative Impact of Harm Reduction on the Swiss HIV Epidemic: Cohort Study, Mathematical Model, and Phylogenetic Analysis

Background

Human immunodeficiency virus (HIV) transmission among injecting drug users (IDUs) is increasing in the United States due to the recent opioid epidemic and is the leading mode of transmission in Eastern Europe.

Methods

To evaluate the overall impact of HIV harm reduction, we combined (1) data from the Swiss HIV Cohort Study and public sources with (2) a mathematical model expressed as a system of ordinary differential equations. The model reconstructs the national epidemic from the first case in 1980 until 2015. Phylogenetic cluster analysis of HIV-1 pol sequences was used to quantify the epidemic spillover from IDUs to the general population.

Results

Overall, harm reduction prevented 15903 (range, 15359–16448) HIV infections among IDUs until the end of 2015, 5446 acquired immune deficiency syndrome (AIDS) deaths (range, 5142–5752), and a peak HIV prevalence of 50.7%. Introduction of harm reduction 2 years earlier could have halved the epidemic, preventing 3161 (range, 822–5499) HIV infections and 1468 (range, 609–2326) AIDS deaths. Suddenly discontinuing all harm reduction in 2005 would have resulted in outbreak re-emergence with 1351 (range, 779–1925) additional HIV cases. Without harm reduction, the estimated additional number of heterosexuals infected by HIV-positive IDUs is estimated to have been 2540 (range, 2453–2627), which is equivalent to the total national reported incidence among heterosexuals in the period of 2007 to 2015.

Conclusions

Our results suggest that a paramount, population-level impact occurred because of the harm reduction package, beyond factors that can be explained by a reduction in risk behavior and a decrease in the number of drug users over time.

Ethnic- and gender-specific differences in the prevalence of HIV among patients in opioid maintenance treatment-a case register analysis

BACKGROUND

We have sought to identify ethnic- and gender-specific differences in HIV prevalence among heroin users receiving opioid maintenance treatment in the canton of Zurich, Switzerland.

METHODS

We used a generalized linear model (GEE) to analyze data from the anonymized case register for all opioid maintenance treatments in the canton of Zurich. Patients who received either methadone or buprenorphine between 1991 and 2012 (n=11,422) were evaluated for gender (male vs. female), ethnic background (Swiss vs. non-Swiss), and lifetime method of drug use (ever injector vs. non-injector). We addressed missing data by multiple imputation.

RESULTS

The overall prevalence of HIV among patients declined substantially from 33.7% in 1991 to 10.6% in 2012 in the complete dataset. In the imputed datasets, the respective prevalence dropped from 32.8% in 1991 to 9.7% in 2012. Non-injectors had a four to five times lower risk ratio (RR) compared to the reference group, 'Swiss males who ever injected'. In addition, we found a significantly higher risk ratio of HIV prevalence among females who had ever injected; this was true both for the complete dataset and the imputed dataset (Swiss RR 1.18 CI 95% 1.04-1.34, non-Swiss RR 1.58 CI 95% 1.18-2.12).

CONCLUSION

In this population, gender, ethnic background, and lifetime method of drug use influenced the risk of being HIV positive. Different access to treatment and different characteristics of risk exposure among certain subgroups might explain these findings. In particular, the higher risk for women who inject drugs-especially for those with an immigrant background-warrants additional research. Further exploration should identify what factors deter women from using available HIV-prevention measures and whether and how these measures can be better adapted to high-risk groups.

A high proportion of users of low-threshold facilities with needle exchange programmes in Switzerland are currently on methadone treatment: implications for new approaches in harm reduction and care

BACKGROUND

Increasingly, patients receiving methadone treatment are found in low threshold facilities (LTF), which provide needle exchange programmes in Switzerland. This paper identifies the characteristics of LTF attendees receiving methadone treatment (MT) compared with other LTF attendees (non-MT).

METHODS

A national cross-sectional survey was conducted in 2006 over five consecutive days in all LTF (n=25). Attendees were given an anonymous questionnaire, collecting information on socio-demographic indicators, drug consumption, injection, methadone treatment, and self-reported HIV and HCV status. Univariate analysis and logistic regression were performed to compare MT to non-MT. The response rate was 66% (n=1128).

RESULTS

MT comprised 57.6% of the sample. In multivariate analysis, factors associated with being on MT were older age (OR: 1.38), being female (OR: 1.60), having one's own accommodation (OR: 1.56), receiving public assistance (OR: 2.29), lifetime injecting (OR: 2.26), HIV-positive status (OR: 2.00), and having consumed cocaine during the past month (OR: 1.37); MT were less likely to have consumed heroin in the past month (OR: 0.76, not significant) and visited LTF less often on a daily basis (OR: 0.59). The number of injections during the past week was not associated with MT.

CONCLUSIONS

More LTF attendees were in the MT group, bringing to light an underappreciated LTF clientele with specific needs. The MT group consumption profile may reflect therapeutic failure or deficits in treatment quality and it is necessary to acknowledge this and to strengthen the awareness of LTF personnel about potential needs of MT attendees to meet their therapeutic goals.

Differences in drug consumption, comorbidity and health service use of opioid addicts across six European urban regions (TREAT-project)

OBJECTIVES

This comparative study investigated consumption patterns, comorbidity and treatment utilization of opioid addicts in six European cities (Athens, Essen, London, Padua, Stockholm, Zurich).

SUBJECTS AND METHODS

Data were collected by structured face-to-face interviews. The representative sample comprises 599 addicts (100 patients per centre, 99 in London) at the start of a treatment episode.

RESULTS

Patients were dependent on opioids for about 10 years. Regional differences were significant regarding the patients' drug consumption pattern and their method of heroin administration (up to a fourth of the patients in Essen, London and Zurich usually smoke heroin). Concomitant use of benzodiazepines, cannabis and alcohol was common in all regions with the German and English samples showing the highest level of polydrug use. The prevalence of major depression was high in all regions (50%). Stockholm and London patients worry most about their physical health. Differences in the amount of needle sharing and especially in the use of public health service were prominent between the sites. Opioid addiction was a long-term disorder associated with a high burden of comorbidity and social problems in all cities.

CONCLUSION

The results of the study show significant interregional differences of opioid addicts which might require different treatment strategies in European countries to handle the problem.

Mapping HIV/STI behavioural surveillance in Europe

BACKGROUND

Used in conjunction with biological surveillance, behavioural surveillance provides data allowing for a more precise definition of HIV/STI prevention strategies. In 2008, mapping of behavioural surveillance in EU/EFTA countries was performed on behalf of the European Centre for Disease prevention and Control.

METHOD

Nine questionnaires were sent to all 31 member States and EEE/EFTA countries requesting data on the overall behavioural and second generation surveillance system and on surveillance in the general population, youth, men having sex with men (MSM), injecting drug users (IDU), sex workers (SW), migrants, people living with HIV/AIDS (PLWHA), and sexually transmitted infection (STI) clinics patients. Requested data included information on system organisation (e.g. sustainability, funding, institutionalisation), topics covered in surveys and main indicators.

RESULTS

Twenty-eight of the 31 countries contacted supplied data. Sixteen countries reported an established behavioural surveillance system, and 13 a second generation surveillance system (combination of biological surveillance of HIV/AIDS and STI with behavioural surveillance). There were wide differences as regards the year of survey initiation, number of populations surveyed, data collection methods used, organisation of surveillance and coordination with biological surveillance. The populations most regularly surveyed are the general population, youth, MSM and IDU. SW, patients of STI clinics and PLWHA are surveyed less regularly and in only a small number of countries, and few countries have undertaken behavioural surveys among migrant or ethnic minorities populations. In many cases, the identification of populations with risk behaviour and the selection of populations to be included in a BS system have not been formally conducted, or are incomplete. Topics most frequently covered are similar across countries, although many different indicators are used. In most countries, sustainability of surveillance systems is not assured.

CONCLUSION

Although many European countries have established behavioural surveillance systems, there is little harmonisation as regards the methods and indicators adopted. The main challenge now faced is to build and maintain organised and functional behavioural and second generation surveillance systems across Europe, to increase collaboration, to promote robust, sustainable and cost-effective data collection methods, and to harmonise indicators.

Giving away used injection equipment: missed prevention message?

Background

Our objective was to examine factors associated with distributive injection equipment sharing and how needle exchange programs (NEPs) can help reduce distributive sharing among injection drug users (IDUs).

Methods

145 English speaking Canadian IDUs ages 16 years and over who had injected in the past 30 days were recruited for a cross-sectional survey. Participants were asked about their socio-demographic characteristics, HIV risk behaviours, social support, drug treatment readiness, program satisfaction, health and social service use and NEP drug use. Bivariate statistics and logistic regression were used to characterize the population and examine correlates of sharing behaviour.

Results

More IDUs reported distributive sharing of cookers (45%) than needles (36%) or other types of equipment (water 36%; filters 29%; swabs 8%). Regression analyses revealed the following factors associated with distributing used cookers: a history of cocaine/crack injection, an Addiction Severity Index (ASI) score indicative of a mental health problem, and older than 30 years of age. Factors associated with giving away used water included: male, injected methadone, injected other stimulants and moved 3+ times in the past 6 months. Factors associated with giving away used filters included: injected cocaine/crack or stayed overnight on the street or other public place. Factors associated with giving away swabs included: an ASI mental health score indicative of a mental health problem, and HCV negative status.

Conclusions

Our findings show that more IDUs give away cookers than needles or other injection equipment. While the results showed that correlates of sharing differed by piece of equipment, each point to distributive sharing by the most marginalized IDUs. Targeting prevention efforts to reduce equipment sharing in general, and cookers in particular is warranted to reduce use of contaminated equipment and viral transmission.

Typology of injection profiles of clients of a supervised drug consumption facility in Geneva, Switzerland

The use of a supervised drug consumption room (DCR) in a newly established low threshold facility in Geneva, Switzerland, in 2002 is analyzed. Two sources of routine data were used: data collected at the first visit by any new client (entry questionnaire) which included some personal details, and data collected on the substances injected at each visit to the DCR. A typology of injection profiles was constructed. Overall, the mean number of injections and days of visits per client over the year was low and cocaine was the main substance injected. However, an important heterogeneity in the use of the DCR was found and five types of clients identified: 1-day clients; standard clients; heroin-oriented clients; high cocaine consumption clients, and newcomers. Typology was associated with some characteristics at the first visit and the drug consumption pattern in the month preceding the first visit was in accordance with the subsequent use of the DCR. This heterogeneity in the use of the DCR highlights the diverse roles of the DCRs in harm reduction.