**Embargo: 09:01 AM [AEST], Thursday 29 August, 2013**
- UK, USA, South Africa, and Australia all had notably high overall burdens of death and illness due to illicit drug use.
- Death and disability in the worst affected countries, including the USA, UK and Australia, was 20 times greater than in the least affected countries.
- The biggest source of burden of disease was opioid dependence followed by amphetamine dependence and injecting drug use as a risk factor for blood-borne viruses (hepatitis B, C and HIV).
- Highest levels of opioid dependence were in Australasia and Western Europe. Highest prevalence of cocaine dependence was in North America & Latin America.
- Disability and illness caused by opioid dependence increased by over 74% between 1990 and 2010.
- Drug dependence and disease burden were highest in men aged 20 – 29 years.
The first ever analysis of the global and regional prevalence of dependence upon the four major categories of illicit drugs – amphetamine, cannabis, cocaine, and opioids (such as heroin) – has revealed that opioid dependence causes the greatest health burden (overall death and illness) of all the illicit drugs. The results come from new analysis of the Global Burden of Disease Study 2010, and are published in The Lancet.
Led by Professor Louisa Degenhardt, from the National Drug and Alcohol Research Centre at the University of New South Wales, a team of researchers in Australia and the US performed a comprehensive search of available data on the prevalence and effects of amphetamines, cannabis, cocaine, and opioids. Other drugs, including MDMA (ecstasy) and hallucinogens such as LSD, were not separately included in the analysis due to a lack of high quality data on their prevalence and health effects.
The results show that the burden in the worst affected countries (largely high-income nations such as USA, UK, and Australia) was 20 times greater than in the least affected countries. Regional breakdown of the results shows that the highest prevalence of cocaine dependence was in North America & Latin America, and among the highest levels of opioid dependence were in Australasia and Western Europe. The UK, USA, South Africa, and Australia all had notably high overall burdens of death and illness due to illicit drugs.
“Our results clearly show that illicit drug use is an important contributor to the global disease burden, and we now have the first global picture of this cause of health loss,” said Professor Degenhardt.
“Young men aged 20-29 are disproportionately affected at a crucial time in their lives.”
Much can be done to reduce this burden, she said.
“Although we have fewer means of responding to some causes of burden, such as cocaine and amphetamine dependence, well-evaluated and effective interventions can substantially reduce two major causes of burden— opioid dependence and injecting drug use. The challenge will be to deliver these efficiently and on a scale needed to have an effect on a population level.
“Effective strategies to reduce the burden of opioid dependence and injecting drug use include opioid substitution treatment.”
For all of the drugs studied, over two thirds of dependent individuals were male (64% each for cannabis and amphetamines, and 70% each for opioids and cocaine). All forms of drug dependence and disease burden were highest in men aged 20 – 29 years.
Although the results show that cannabis is by far the most commonly used illicit drug worldwide, the prevalence of cannabis dependence (13.0 million people worldwide) was somewhat lower than for amphetamines (17.2 million) and opioids (15.5 million), the two most common forms of illicit drug dependence.
The biggest source of burden of disease was opioid dependence, followed by amphetamine dependence, and injecting drug use as a risk factor for blood-borne viruses (hepatitis B, C and HIV). Cannabis and cocaine dependence were more modest sources of disease burden, due to the smaller size of these populations and the lower levels of disability associated with these drugs.
By using the same methods to estimate burden as in 1990 in this study, the researchers were also able to examine trends over time. They found that disability and illness caused by the four drugs studied has increased by over 50% between 1990 and 2010. Although some of this increase is due to increasing population size, over a fifth (22%) of the increase is thought to be due to increasing prevalence of drug use disorders, particularly for opioid dependence. Of the around 78,000 deaths in 2010 attributed to drug disorders, more than half (55%) were thought to be due to opioid dependence.
Despite the substantial preventable disease burden found to be attributable to the four drugs studied, their overall burden is still less than that of smoking and alcohol, which are together responsible for around 10% [6.3+3.9] of the total death and illness burden worldwide. The new study estimates that illicit drug dependence contributes to just under 1% of the total global burden of death and illness. However, given the large differences in the prevalence of illicit drug dependence compared to alcohol dependence and tobacco use, it is clear that illicit drug use causes comparatively more burden per person.
- Ends -
For the full paper, see: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(13)61530-5/abstract
For comment on this paper, see: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(13)61781-X/abstract
For interviews with Professor Louisa Degenhardt, please contact Marion Downey, Media and Communications Manager, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, Australia.
+61 (02) 9385 0333 (office) / +61 (04) 0171 3850 / m.downey@unsw.edu.au
The National Drug and Alcohol Research Centre at the University of New South Wales is supported by funding from the Australian Government under the Substance Misuse Prevention and Service Improvements Grants Fund.
