Health Consequences of Psychoactive Substance Use: Implications for Policies

Mr/Mrs Chairman, Ladies and Gentlemen,

As a representative of the Department of Mental Health and Substance Abuse in the WHO Headquarters in Geneva, I am grateful for having this opportunity to bring to this discussion some global issues and perspectives from our office, which might be relevant to the debate on a changing European Drug Policy.

The World Health Organization, as the leading public health agency in the world, is concerned with health consequences and health risks associated with all psychoactive substances irrespective of social and legal status of their consumption: from licit substances, like tobacco and alcohol - to psychotropic medicines and illicit drugs.

The WHO’s mandate in the area of psychoactive substance use includes:

• prevention and reduction of the negative health and social consequences of psychoactive substance use;

• reduction of the demand for non-medical use of psychoactive substances;

• assessment of psychoactive substances by the WHO Expert Committee on Drug Dependence so as to advise the United Nations with regard to their regulatory control.

The prevention and reduction of the health consequences of psychoactive substance use, and the role of the health sector in achieving these goals, are some of the main focuses of our programme.

Health burden of psychoactive substance use

The health burden of psychoactive substance use is substantial and results in deaths, diseases and disabilities. For the assessment of mortality and disability from diseases, injuries and health risk factors throughout the world, the World Health Organization initiated the Global Burden of Disease Study. In this study the disease burden is expressed in so-called Disability-Adjusted Life Years or DALYs, which combines the impact of premature death and disability. According to WHO estimates, psychoactive substance use is an increasingly important factor for health globally, and, according to WHO estimates of associated mortality and morbidity, the largest global burden of disease is associated with the use of licit psychoactive substances, which are used by the largest number of people in the world. The tobacco epidemic claims 4.9 million lives each year, constituting the single largest preventable cause of death worldwide. Alcohol is responsible for 1.8 million deaths annually and 4.1% of the total Disability Adjusted Life Years (DALYs). 0.2 million deaths and 0.8% of all DALYs are attributed to illicit drug use. However, in industrialized countries, illicit drugs account for 2-4% of all disease burden among men.

Current data indicates that the main global health burden is associated with consumption of licit rather than illicit substances, though in developed countries the proportion of burden associated with illicit drugs is larger, and public health response to substance use should be proportional to the health-related harm that they cause. Emphasizing the health consequences of legal substances that are accepted in the society tends to underline the generally hazardous nature of any psychoactive substance use and facilitates preventive strategies and interventions.

Injecting drug use and HIV/AIDS

The HIV/AIDS epidemics among injecting drug users have had serious implications for policy responses. The population of injecting drug users comprises approximately 10 million people worldwide. In many parts of the world-injecting drug use is a driving force behind the epidemic. Whereas in the Western Europe, just over 10% of newly diagnosed HIV cases in 2002 were caused by injecting drug use. In Eastern Europe and Central Asia this figure is over 50% and some 230,000 people were infected with HIV in 2003. HIV risk among substance users is not only related exclusively to injection behaviour. Substance use, including alcohol and stimulants, affect individual vulnerability to HIV infection and sexually transmitted diseases by unsafe sexual behaviour, and the potential of diffusion of HIV to the general population remains high.

As a highly effective way of transmitting blood-borne pathogens, drug injection is associated with not only HIV transmission, but transmission of viral hepatitis as well. Hepatitis C is one of the major health challenges of the modern world. In industrialized countries it accounts for 20% of episodes of acute hepatitis, 40% of cases of end-stage cirrhosis, 60% of cases of hepatocellular carcinoma and 30% of liver transplants. The seroprevalence of hepatitis C is relatively low in the general population, but among injecting drug users this prevalence is much higher and, for example, among old drug injectors - 86% (70% in Spain and 60-70% in Australia).

In response to the HIV/AIDS epidemic among hard-to-reach populations of injecting drug users, different types of harm- or risk-reduction programs started to develop, including needle-exchange programs and condom and bleach distribution. Sometimes substitution therapy of opioid dependence is being mentioned as harm-reduction intervention. The UNGASS Declaration for the Commitment on HIV/AIDS, adopted in 2001, specifically mentioned harm-reduction efforts related to drug use among prevention interventions, which should take into account of local circumstances, ethical and cultural values, and the WHO in collaboration with UNAIDS and other co-sponsors is involved in numerous activities targeted at promoting HIV preventive policies and programs among injecting drug users.

A growing number of drug-dependent people with HIV/AIDS presents an enormous challenge to health care systems. The “3 by 5” initiative of the World Health Organization envisages a provision of ARV therapy to those in need, including drug-dependent injecting drug users. People with substance dependence and HIV/AIDS should have equal access to HIV/AIDS medical care, and this requires better integration and linking of treatment services. The HIV/AIDS epidemic emphasized the previously stated position from the WHO that “the development of treatment services for drug-related problems should be integrated with that of mental health services and the primary and general health services, and resources allocated accordingly to maximize their effectiveness” (WHO Expert Committee on Drug Dependence. 28th Report. Geneva 1993).

Drug dependence and access to treatment

Substance dependence is a health disorder. The WHO Report on Neuroscience of Substance Use and Dependence, which will be coming out soon, will concentrate on advances in our understanding of the nature of substance dependence as a disorder with strong involvement of brain mechanisms, as in other mental and behavioural disorders, and substance dependence should be treated as such.

There is a continued need to improve the quality and expand on the coverage of treatment and integrate drug dependence treatment into the overall health care system with strong involvement of primary health care. With our current understanding of drug dependence as often being a chronic and relapsing disorder, a response from the health care system should be up to date with this understanding. Effective treatment is available and it should be accessible to all those in need. The most cost-effective interventions should be provided by the public health care sector. Most people with substance dependence express a strong desire to be abstinent, but remain ambivalent about treatment. Usually some sort of a crisis triggers a treatment episode, and it is important that treatment is readily available and accessible.

Substitution therapy of opioid dependence.

In the area of drug treatment policy, substitution maintenance therapy for opioid dependence has been a controversial issue and in some countries it is still not considered as a treatment option. The World Health Organization, the United Nations Office on Drugs and Crime and the Joint United Nations Programme on HIV/AIDS have developed a joint position on substitution maintenance therapy for opioid dependence, where substitution therapy is considered as a critical component of community-based approaches in the management of opioid dependence and the prevention of HIV transmission among injection drug users in the countries with high prevalence of opioid injecting. With the growing number of opioid dependent people with HIV/AIDS, substitution maintenance therapy should be given serious consideration as an important component and sometimes as a platform for HIV/AIDS treatment and care.

Prescribing heroin as an opioid substitution therapy for severely dependent individuals has been debated extensively in the press, but quite a limited amount of research data actually exists on the feasibility and effectiveness of this treatment approach. In research trials in Switzerland and the Netherlands patients in heroin-assisted treatment demonstrated improvement in their health status and social functioning. However, the contribution of heroin itself and other components of the comprehensive programme have to be researched further. This treatment approach is complex and costly, has been evaluated only in developed countries with comprehensive drug abuse treatment systems, and only a small proportion of patients can benefit when all other available treatment options for them have failed.

Public health, security and control

The mission of the World Health Organization is to assist Member States in reducing the morbidity and mortality from substance use and substance use disorders and improve the quality of life of people suffering from substance dependence. Due to the nature of substance dependence, high levels of psychiatric and somatic comorbidity among drug users including HIV/AIDS and tuberculosis, require an integrated public health approach to the problem, which comprises of epidemiology, prevention, treatment, rehabilitation and reintegration into society.

People with substance dependence often come into contact with the criminal justice system. In some countries, a high level of drug use-related arrests has a negative impact on the quality of drug treatment, whereas in other countries the preference is given to the benefits of undergoing treatment rather than imprisonment. In many countries, treatment for substance use disorders is not available within prisons, even when imprisonment is appropriate. Investment in public health measures to reduce the burden of substance use can be compatible with and supplement law enforcement and control. But to incarcerate drug-dependent people for drug use and their dependence is not an effective prevention and treatment strategy.

Together with regulatory and control measures, a comprehensive public health approach, including prevention and treatment policies, as well as other strategies and interventions aimed at reducing substance use-related risks, should be an important and prominent component of drug policies worldwide.