Effects of reduction in heroin supply on injecting drug use: analysis of data from needle and syringe programmesBMJ 2004; 329 doi: http://dx.doi.org/10.1136/bmj.38201.410255.55 (Published 19 August 2004) Cite this as: BMJ 2004;329:428
- Carolyn Day, doctoral candidate ()1,
- Louisa Degenhardt, lecturer1,
- Stuart Gilmour, statistician1,
- Wayne Hall, professor2
- 1 National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW 2052, Australia
- 2 Office of Public Policy and Ethics, Institute for Molecular Bioscience, University of Queensland, St Lucia, Brisbane, QLD 4072, Australia
- Correspondence to: C Day
- Accepted 23 June 2004
In early 2001 there was a dramatic decline in the availability of heroin in New South Wales (NSW), Australia, where previously heroin had been readily available at a low price and high purity.1 The decline was confirmed by Australia's strategic early warning system, which revealed a reduction in heroin supply across Australia and a considerable increase in price,2 particularly from January to April 2001.
This “heroin shortage” provided a natural experiment in which to examine the effect of substantial changes in price and availability on injecting drug use and its associated harms in Australia's largest heroin market,2 a setting in which harm reduction strategies were widely used. Publicly funded needle and syringe programmes were introduced to Australia in 1987, and methadone maintenance programmes, which were established in the 1970s, were significantly expanded in 1985 and again in 1999.
Methods and results
In NSW needle and syringe programmes are delivered primarily within the public sector through area health services. There is also a private sector programme, subsidised by the government, delivered through pharmacies (known as “fitpacks”). This enables injecting drug users to purchase or exchange needles and syringes. We used data collected by these programmes to examine the extent of injecting drug use. These data are representative of all needles and syringes distributed to injecting drug users in NSW and have been combined to produce quarterly comparable data.
The number of needles and syringes distributed in NSW decreased around the onset of the heroin shortage (figure) and the reduction was sustained until the end of the period for which data were available. The number of needles distributed decreased from around 3.1 million per quarter immediately before the heroin shortage to just under 2.2 million in mid-2002—a decrease of around 28%. Time series analysis on monthly data from major needle and syringe programmes suggested that this decline was not a seasonal effect and was tied closely to the onset of the shortage (analysis available on request).
We found a sustained reduction in the number of needles and syringes distributed in NSW after a considerable decrease in heroin supply. Given the widespread and easy availability of needles and syringes in NSW, the data on provision are a useful proxy for changes in the number of injecting drug users or in the frequency of injecting, or both. The trends observed here were also consistent with estimated reductions in the number of regular heroin users after the heroin shortage.3 These data suggest an overall reduction in the prevalence of injecting drug use after a decrease in heroin supply.
We relied on secondary data sources as indirect measures of the prevalence of injecting drug use. None the less, the coherent pattern of changes outlined in this study is not easily explained by any other hypotheses and is consistent with other research on the consequences of the heroin shortage.3
Our findings are also consistent with a reduction in notifications of hepatitis C among people aged 15-19 years, which started around the time of the reduction in heroin supply.4 Nearly all such infections are related to injecting drug use, and there are no alternative explanations for the decrease in notifications, which was not predicted by mathematical models of the hepatitis C epidemic in Australia.5 However, the true impact of reduced supply is unlikely to be detectable for some time. Reduction in injecting drug use, as indicated by reduced output in the needle and syringe programmes, would be consistent with reduction in such infections at the population level. We are currently exploring further impacts of the shortage on overdose, treatment, and crime.
What is already known on this topic
The impact of reduced heroin supply on injecting drug use (where this is the drug of choice) has not previously been determined
What this study adds
Reduced heroin supply is associated with reduced injecting drug use
This article was posted on bmj.com on 3 August 2004: http://bmj.com/cgi/doi/10.1136/bmj.38201.410255.55
We thank the many agencies and individuals who provided advice and data for inclusion in the study; Linette Collins, Amy Gibson, and Elizabeth Conroy for assistance with the project; and Owen Westcott and Jenny Iverson from the AIDS and Infectious Diseases Branch of NSW Health for facilitating access to NSW notification and programme data. We also thank Greg Dore, Lisa Maher, and Margaret MacDonald for comments on an earlier draft of the paper.
Contributors CD (guarantor), LD, and WH conceived the study. LD supervised the research. CD led the writing. SG conducted the analysis for the study. All authors helped to conceptualise ideas, interpret findings, and review drafts of the manuscript.
Funding This work was completed as part of a larger project funded by the Australian National Drug Law Enforcement Research Fund (NDLERF). The National Drug and Alcohol Research Centre is funded by the Australian Government Department of Health and Ageing. CD was funded by a postgraduate award from the Australian Government Department of Health and Ageing.
Competing interests None declared.
Ethical approval The study was approved by the University of New South Wales human research ethics committee and the human research ethics committees of the South Eastern Sydney Area Health Service, South Western Area Health Service, and Central Sydney Area Health Service.