Page 10 - Pagetit

Foreword

Substance use and dependence cause a significant burden to individuals and
societies throughout the world. The World Health Report 2002 indicated that
8.9% of the total burden of disease comes from the use of psychoactive
substances. The report showed that tobacco accounted for 4.1%, alcohol 4%,
and illicit drugs 0.8% of the burden of disease in 2000. Much of the burden
attributable to substance use and dependence is the result of a wide variety
of health and social problems, including HIV/AIDS, which is driven in many
countries by injecting drug use.
This neuroscience report is the first attempt by WHO to provide a
comprehensive overview of the biological factors related to substance use
and dependence by summarizing the vast amount of knowledge gained in
the last 20-30 years. The report highlights the current state of knowledge of
the mechanisms of action of different types of psychoactive substances, and
explains how the use of these substances can lead to the development of
dependence syndrome.
Though the focus is on brain mechanisms, the report nevertheless
addresses the social and environmental factors which influence substance
use and dependence. It also deals with neuroscience aspects of interventions
and, in particular, the ethical implications of new biological intervention
strategies.
The various health and social problems associated with use of and
dependence on tobacco, alcohol and illicit substances require greater
attention by the public health community and appropriate policy responses
are needed to address these problems in different societies. Many gaps remain
to be filled in our understanding of the issues related to substance use and
dependence but this report shows that we already know a great deal about
the nature of these problems that can be used to shape policy responses.
This is an important report and I recommend it to a wide audience of health
care professionals, policy makers, scientists and students.

LEE Jong-wook
Director General
World Health Organization

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Pagetit 9 19.1.2004, 12:36