WORLD HEALTH ORGANIZATION The WORLD HEALTH REPORT 2002 Re educe ag Risks, Promoting Healthy life
educing isks, Promoting Healthy Life he W O RLD HEALTH R EPORT 2002 WORLD HEALTH ORGANIZATION
WHO Library Cataloguing in Publication Data The World health report: 2002: Reducing risks, promoting healthy life Risk assessment 3. Epidemiologic methods 5. Risk management-methods 6 Public policy 7. Quality of life rends ITitle II.Title: Reducing risks, promoting life SBN 92 4 156207 2(NLM Classification: WA 540.1) ISSN1020-3311 o World Health Organization 2002 All rights reserved Publications of the World Health Organization can be obtained from Marketing and Dissemination, Wor Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: bookorders(@who. int). Requests for permission to reproduce or translate WHO publications hether for sale or for noncommercial distribution - should be addressed to Publications, at the above address(fax: +41 22 791 4806; email: permissions@who. int) The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal or area or of its authorities, or concerning the delimitation of it frontiers or boundaries Dotted lines on maps represent approximate border lines for which there t be full agreement r of certain manufacturers products does not imply that endorsed or recommended by the World Health Organization in preference to others of a similar that are not mentioned Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damages incurred as a result of its use. Information ming this publication can be obtained from World Health Report World Health Organization 1211 Geneva 27, Switzerland Email: whr(@who int Fax:(41-22)7914870 Copies of this publication can be ordered from: bookorders(@who int This report was produced under the overall direction of Christopher Murray ters, and senior policy advisers to the Director-General. and Alan Lopez. The two principal authors were Anthony Rodgers(Chap- The risk assessments in this report were coordinated by Majid Ezzati, ters 2&4)and Patrick Vaughan(Chapters 3&6). The Overview and Chapter Alan Lopez and Anthony Rodgers, with statistical analyses by Stephen 1 were written by Thomson Prentice. All of the above contributed to Chap- Vander Hoom. The assessments are the result of several years'work by many ter 7. Chapter 5 was written by Tessa Tan-Torres Edejer, David Evans and scientists worldwide. These scientists are listed in the Acknowledgements, Julia Lowe as are the many WHO specialists who worked on the cost-effectiveness as The report was edited by Barbara Campanini, with assistance from Hoorn Angela Haden. The figures, maps and tables were coordinated by Michel Valuable input was received from an internal advisory group and a re- Beusenberg. Translation coordination and other administrative and pr gional reference group, the members of which are listed in the Acknowl- duction support for the World Health Report team was provided by shelagh edgements. Additional help and advice were appreciated from regional Probst. Further assistance was given by Patrick Unterlerchner The indexw directors, executive directors and members of their staff at WHO headquar- prepared by Liza Furnival. Cover illustration by Laura de Santis Design by Marilyn Langfeld Layout by WHO Graphics Printed in france 2002/14661- Sadao-2500
ii The World Health Report 2002 Cover illustration by Laura de Santis Design by Marilyn Langfeld. Layout by WHO Graphics Printed in France 2002/14661 – Sadag – 25000 WHO Library Cataloguing in Publication Data. The World health report : 2002 : Reducing risks, promoting healthy life. 1.Risk factors 2.Risk assessment 3.Epidemiologic methods 4.Cost of illness 5.Risk management - methods 6.Public policy 7.Quality of life 8.World health - trends I.Title II.Title: Reducing risks, promoting life. ISBN 92 4 156207 2 (NLM Classification: WA 540.1) ISSN 1020-3311 © World Health Organization 2002 All rights reserved. Publications of the World Health Organization can be obtained from Marketing and Dissemination, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: bookorders@who.int). Requests for permission to reproduce or translate WHO publications – whether for sale or for noncommercial distribution – should be addressed to Publications, at the above address (fax: +41 22 791 4806; email: permissions@who.int). The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement. The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damages incurred as a result of its use. Information concerning this publication can be obtained from: World Health Report World Health Organization 1211 Geneva 27, Switzerland Email: whr@who.int Fax: (41-22) 791 4870 Copies of this publication can be ordered from: bookorders@who.int This report was produced under the overall direction of Christopher Murray and Alan Lopez. The two principal authors were Anthony Rodgers (Chapters 2 & 4) and Patrick Vaughan (Chapters 3 & 6). The Overview and Chapter 1 were written by Thomson Prentice. All of the above contributed to Chapter 7. Chapter 5 was written by Tessa Tan-Torres Edejer, David Evans and Julia Lowe. The writing team was greatly assisted by Michael Eriksen, Majid Ezzati, Susan Holck, Carlene Lawes, Varsha Parag, Patricia Priest and Stephen Vander Hoorn. Valuable input was received from an internal advisory group and a regional reference group, the members of which are listed in the Acknowledgements. Additional help and advice were appreciated from regional directors, executive directors and members of their staff at WHO headquarters, and senior policy advisers to the Director-General. The risk assessments in this report were coordinated by Majid Ezzati, Alan Lopez and Anthony Rodgers, with statistical analyses by Stephen Vander Hoorn. The assessments are the result of several years’ work by many scientists worldwide. These scientists are listed in the Acknowledgements, as are the many WHO specialists who worked on the cost-effectiveness assessment section. The report was edited by Barbara Campanini, with assistance from Angela Haden. The figures, maps and tables were coordinated by Michel Beusenberg. Translation coordination and other administrative and production support for the World Health Report team was provided by Shelagh Probst. Further assistance was given by Patrick Unterlerchner. The index was prepared by Liza Furnival
CONTENTS MESSAGE FROM THE DIRECTOR-GENERAL OVERVIEW Introduction Enemies of health, allies of poverty Recommended actions Summary of chapters CHAPTER 1 PROTECTING THE PEOPLE Reducing the risks 3 The risk transition CHAPTER 2 DEFINING AND ASSESSING RISKS TO HEALTH What are risks to health? why focus on risks to health? 799 Development of risk assessment Key goals of global risk assessment Standardized comparisons and common outcome measures Assessing protective as well as hazardous factors Including proximal and distal causes 13 Assessing population-wide risks as well as high-risk individuals Including risks that act together to cause disease Using best available evidence to assess certain and probable risks to health 16 Assessing avoidable as well as attributable burden 17 Overview of risk assessment methods Choosing and defining risks to health Estimating current risk factor levels and choosing counterfactuals Estimating current and future disease and injury burden Estimates of avoidable burden Estimating the joint effects of multiple risks Estimates of uncertainty CHAPTER 3 PERCEIVING RISKS Changing perceptions of risk Emerging importance of risk perceptions Questioning the science in risk assessmen Risk perceptions Defining and describing risks to health 323 raming the information on risks ocial and cultural interpretations of risk Perceptions of health risks in developing countries 37 mportance of risk communications
Overview iii CONTENTS MESSAGE FROM THE DIRECTOR-GENERAL ix OVERVIEW xiii Introduction xiii Enemies of health, allies of poverty xiv Recommended actions xvii Summary of chapters xviii CHAPTER 1 PROTECTING THE PEOPLE 1 Reducing the risks 3 The risk transition 4 CHAPTER 2 DEFINING AND ASSESSING RISKS TO HEALTH 7 What are risks to health? 9 Why focus on risks to health? 9 Development of risk assessment 10 Key goals of global risk assessment 11 Standardized comparisons and common outcome measures 12 Assessing protective as well as hazardous factors 13 Including proximal and distal causes 13 Assessing population-wide risks as well as high-risk individuals 15 Including risks that act together to cause disease 15 Using best available evidence to assess certain and probable risks to health 16 Assessing avoidable as well as attributable burden 17 Overview of risk assessment methods 18 Choosing and defining risks to health 20 Estimating current risk factor levels and choosing counterfactuals 22 Estimating current and future disease and injury burden 22 Estimating risk factor–burden relationships 22 Estimates of avoidable burden 23 Estimating the joint effects of multiple risks 23 Estimates of uncertainty 24 CHAPTER 3 PERCEIVING RISKS 27 Changing perceptions of risk 29 Questioning the science in risk assessment 30 Emerging importance of risk perceptions 31 Risk perceptions 32 Defining and describing risks to health 34 Influences on risk perceptions 35 Framing the information on risks 36 Social and cultural interpretations of risk 36 Perceptions of health risks in developing countries 37 Importance of risk communications 38
The World Health Report 2002 Influence of special interest groups on risk perceptions 39 Importance of mass media in risk perceptions 42 Importance of perceptions in successful risk prevention QUANTIFYING SELECTED MAJOR RISKS TO HEALTH Risks to health and socioeconomic status 49 Rates of poverty across the world Relationships between risk factor levels and poverty Potential impact on risk factor levels of shifting poverty distributions Burden of disease and injury attributable to selected risk factors Childhood and maternal undernutrition 52 52 lodine deficiency Iron deficiency Vitamin a deficiency Zinc deficiency 55 Lack of breastfeeding 56 Other diet-related risk factors and physical inactivity igh blood pressure Obesity, overweight and high body mass Low fruit and vegetable intake 61 Sexual and reproductive health Unsafe sex Lack of contraception Addictive substances Smoking and oral tol acco use Alcohol use 65 Illicit drug u 66 Unsafe water, sanitation and hygiene Urban air pollution Indoor smoke from solid fuels Lead e Climate change Other environmental risks to health Work-related risk factors for injuri Work-related carcinogens Work-related airborne particulates Work-related ergonomic stressors Work-related noise Other risks to health Unsafe health care practices Abuse and violence Global patterns of risks to health 012345万667898888 it all together-what is possibl Estimates of the joint effects of selected risk factors Estimates of avoidable burden The need for cost-effectiveness analyses
iv The World Health Report 2002 Influence of special interest groups on risk perceptions 39 Importance of mass media in risk perceptions 42 Importance of perceptions in successful risk prevention 43 CHAPTER 4 QUANTIFYING SELECTED MAJOR RISKS TO HEALTH 47 Risks to health and socioeconomic status 49 Rates of poverty across the world 50 Relationships between risk factor levels and poverty 50 Potential impact on risk factor levels of shifting poverty distributions 51 Burden of disease and injury attributable to selected risk factors 52 Childhood and maternal undernutrition 52 Underweight 52 Iodine deficiency 54 Iron deficiency 54 Vitamin A deficiency 55 Zinc deficiency 55 Lack of breastfeeding 56 Other diet-related risk factors and physical inactivity 57 High blood pressure 57 High cholesterol 58 Obesity, overweight and high body mass 60 Low fruit and vegetable intake 60 Physical inactivity 61 Sexual and reproductive health 61 Unsafe sex 62 Lack of contraception 63 Addictive substances 64 Smoking and oral tobacco use 64 Alcohol use 65 Illicit drug use 66 Environmental risks 67 Unsafe water, sanitation and hygiene 68 Urban air pollution 68 Indoor smoke from solid fuels 69 Lead exposure 70 Climate change 71 Other environmental risks to health 72 Selected occupational risks 73 Work-related risk factors for injuries 74 Work-related carcinogens 75 Work-related airborne particulates 75 Work-related ergonomic stressors 76 Work-related noise 76 Other risks to health 77 Unsafe health care practices 78 Abuse and violence 79 Global patterns of risks to health 81 Putting it all together – what is possible? 85 Estimates of the joint effects of selected risk factors 85 Estimates of avoidable burden 88 The need for cost-effectiveness analyses 92
Contents CHAPTER S SOME STRATEGIES TO REDUCE RISK From health risks to policy 101 What strategies can reduce risks to health? Risk reduction and behaviour Individual-based versus population approaches to risk reduction The role of government and legislation 105 Different ways of attaining the same goal Technical considerations for cost-effectiveness analysis Choosing interventions to reduce specific risks hildhood undernutrition 0 Childhood undernutrition (and breastfeeding 110 Iron deficiency 110 Vitamin a deficient Zinc deficiency 112 Other individual-based interventions ng on children under five of Combined interventions to reduce risks in children under five years of age Blood pressure and cholesterol 114 lood pressur Cholesterol Combining interventions to reduce the risk of cardiovascular events 116 Low fruit and Unsafe sex and HIVIAIDS Addictive substances Environmental risks Unsafe water, sanitation, and hygiene Occupational risk facto Health practices 130 Unsafe health care injections Combining risk reduction strategies CHAPTER 6 STRENGTHENING RISK PREVENTION POLICIES Choosing priority strategies for risk prevention opulation-based interventions or high-risk individual targets? Distal or proximal risks to health? Primary or secondary prevention? 148 managing the risk prevention process Identifying priority risk factors for prevention Assessment and management of highly uncertain risks Ethical considerations in risk prevention Risk communications and the role of govemments strengthening the scientific evidence base Urgent need for international action
Overview v CHAPTER 5 SOME STRATEGIES TO REDUCE RISK 99 From health risks to policy 101 What strategies can reduce risks to health? 103 Risk reduction and behaviour 103 Individual-based versus population approaches to risk reduction 104 The role of government and legislation 105 Different ways of attaining the same goal 106 Technical considerations for cost-effectiveness analysis 106 Choosing interventions to reduce specific risks 108 Childhood undernutrition 109 Childhood undernutrition (and breastfeeding) 110 Iron deficiency 110 Vitamin A deficiency 111 Zinc deficiency 112 Other individual-based interventions focusing on children under five years of age 112 Combined interventions to reduce risks in children under five years of age 113 Blood pressure and cholesterol 114 Blood pressure 115 Cholesterol 116 Combining interventions to reduce the risk of cardiovascular events 116 Low fruit and vegetable intake 118 Sexual and reproductive health 118 Unsafe sex and HIV/AIDS 118 Addictive substances 123 Smoking 123 Environmental risks 127 Unsafe water, sanitation, and hygiene 127 Occupational risk factors 129 Health practices 130 Unsafe health care injections 130 Combining risk reduction strategies 131 Policy implications 137 CHAPTER 6 STRENGTHENING RISK PREVENTION POLICIES 145 Choosing priority strategies for risk prevention 147 Population-based interventions or high-risk individual targets? 147 Distal or proximal risks to health? 148 Primary or secondary prevention? 148 Managing the risk prevention process 149 Identifying priority risk factors for prevention 150 Assessment and management of highly uncertain risks 151 Ethical considerations in risk prevention 153 Risk communications and the role of governments 154 Strengthening the scientific evidence base 155 Urgent need for international action 156 Contents