A LIFECOURSE APPROACH TO HEALTH WHONME/HPS/00-2 The implications for training of embracing A Life course Approach to Health le CENT World Health Organization
The implications for training of embracing A Life Course Approach to Health A LIFECOURSE APPROACH TO HEALTH World Health Organization WHO/NMH/HPS/00.2 Distr.: General Orig.: English
-ALIFECOURSE APPROACH TO HEALTH Background This brochure was produced as the result of a workshop organised jointly by the World Health Organization and the International Longevity Centre-UK, on the initiative of WHO. The brochure aims to stimulate consideration of the importance and -in practical terms -the effective realisation of a life-course perspective in the training of health-care professionals. With the establishment in 1995 of the Ageing and Health Programme (AHE), WHO firmly embraced the "life course as one of its key perspectives on ageing, as reflected in its programme activities. In late 1999, AHE proposed that ILC-UK conduct this joint workshop and invite not only ILC representatives but also some of the leading life course researchers. We gratefully acknowledge a grant from the Japanese government to WHO which enabled its realisation Population ageing and increasing longevity are necessitating an examination of the skills and training needs of our health care professionals and the capacity of our health care services and systems The meeting organisers believe that the adoption of the 'life course' as a conceptual framework will assist in developing efficient and equitable responses to this challeng The brochure is being disseminated to stimulate wider consideration of the issues and ideas discussed. We are looking to readers -educators and students. -to engage and feedback with thoughts and ideas on taking forward a life course approach-we want to hear from you. cOpyright World Health Organization, 2000 This document is not a formal pubtication of the World Health Organization (W all rights are reserved by the Organizatio The document may, bowever, be freely reviewed, abstracted, reproduced and tra in part or in whole, but not for sale nor in conjunction with commercial purposes. The views expressed in docume amed authors are solely the responsibility of those authors PAGETWO
PAGETWO Background This brochure was produced as the result of a workshop organised jointly by the World Health Organization and the International Longevity Centre-UK, on the initiative of WHO. The brochure aims to stimulate consideration of the importance and – in practical terms – the effective realisation of a life-course perspective in the training of health-care professionals. With the establishment in 1995 of the Ageing and Health Programme (AHE), WHO firmly embraced the ‘life course’ as one of its key perspectives on ageing, as reflected in its programme activities. In late 1999, AHE proposed that ILC-UK conduct this joint workshop and invite not only ILC representatives but also some of the leading life course researchers. We gratefully acknowledge a grant from the Japanese government to WHO which enabled its realisation. Population ageing and increasing longevity are necessitating an examination of the skills and training needs of our health care professionals and the capacity of our health care services and systems. The meeting organisers believe that the adoption of the ‘life course’ as a conceptual framework will assist in developing efficient and equitable responses to this challenge. A LIFECOURSE APPROACH TO HEALTH The brochure is being disseminated to stimulate wider consideration of the issues and ideas discussed. We are looking to readers – educators and students, – to engage and feedback with thoughts and ideas on taking forward a life course approach – we want to hear from you. ©Copyright World Health Organization, 2000 This document is not a formal publication of the World Health Organization (WHO), and all rights are reserved by the Organization. The document may, however, be freely reviewed, abstracted, reproduced and translated, in part or in whole, but not for sale nor for use in conjunction with commercial purposes. The views expressed in documents by named authors are solely the responsibility of those authors
A LIFECOURSE APPROACH TO HEALTH Why promote the life course The importance of the life course as a framework is often downplayed as'common sense 'and its promotion'needless'. In reality however, acceptance of this principle has enormous implications on the way an individual's health is considered, for the training of health care professionals and for the way health systems are developed to cater for individuals' health care needs. Epidemiological research is beginning, and will continue, to enhance our understanding of the relative importance of different stages in the life course in relation to health capital and specific disease processes. Finding will enable the development and fine-tuning of life course models with specific implications for health and social policy interventions. In the meantime, as will be shown, there is value to be gained in acknowledging the importance of adopting a life course approach to health, exploring the issues raised and addressing the challenges that result. In the education and training of health-care professionals, a life course approach offers the potential to enhance the integration of teaching and to prepare students, across both the developed and developing worlds, for carrying out their responsibilities in the twenty-first century. Population of regions of the world Population(in billions 2000 2050 6.055 7.824 More developed countries 1.188 Less developed countries 4.867 6.609 7754 Age >65 years Total 0.419 0.817 1.458 More developed countries 0.254 ess developed countries 0.248 0.563 1.159 Source: United Nations World Population Prospects: The 1998 Revision (Medium Variant Projections) PAGETHREE
PAGETHREE Why promote the life course? The importance of the life course as a framework is often downplayed as ‘common sense’ and its promotion ‘needless’. In reality however, acceptance of this principle has enormous implications on the way an individual’s health is considered, for the training of health care professionals and for the way health systems are developed to cater for individuals’ health care needs. Epidemiological research is beginning, and will continue, to enhance our understanding of the relative importance of different stages in the life course in relation to health capital and specific disease processes. Findings will enable the development and fine-tuning of life course models with specific implications for health and social policy interventions. In the meantime, as will be shown, there is value to be gained in acknowledging the importance of adopting a life course approach to health, exploring the issues raised and addressing the challenges that result. In the education and training of health-care professionals, a life course approach offers the potential to enhance the integration of teaching and to prepare students, across both the developed and developing worlds, for carrying out their responsibilities in the twenty-first century. Population (in billions) 2000 2025 2050 Total 6.055 7.824 8.909 More developed countries 1.188 1.215 1.155 Less developed countries 4.867 6.609 7.754 Age >65 years Total 0.419 0.817 1.458 More developed countries 0.171 0.254 0.299 Less developed countries 0.248 0.563 1.159 Source: United Nations. World Population Prospects: The 1998 Revision. (Medium Variant Projections) A LIFECOURSE APPROACH TO HEALTH Population of regions of the world
A LIFECOURSE APPROACH TO HEALTH a life course approach to health A life course approach emphasises a temporal and social perspective, looking back across an individual's or a cohort's life experiences or across generations for clues to current patterns of health and disease, whilst recognising that both past and present experiences are shaped by the wider ocial, economic and cultural context. In epidemiology, a life course approach is being used to study he physical and social hazards during gestation, childhood, adolescence, young adulthood nd midlife that affect chronic disease risk and health outcomes in later life. It aims to identify the underlying biological, behavioural and psychosocial processes that operate across the life span(Kuh and Ben-Shlomo, 1997) A life course approach incorporates, but is broader than, 'the fetal origins hypothesis'(programming) hich links conditions in the intrauterine environment to the later development of adult chronic disease(Barker, 1998). Growing evidence suggests that there are critical periods of growth and development, not just in utero and early infancy but also during childhood and adolescence, when environmental exposures do more damage to health and long-term health potential than they would at other times. There is also evidence of sensitive developmental stages in childhood and adolescence when social and cognitive skills, habits, coping strategies, attitudes and values are more easily acquired than at later ages. These abilities and skills strongly influence life course trajectories with implications for health in later life. Additionally, a life course approach considers the long term health consequences of biological and social experiences in early and mid adulthood, and whether these factors simply add additional risk or act interactively with early life biological and social factors, to attenuate or exacerbate long term risks to health Cumulative effects on later health may occur not only across an individual's life but also across generations(Lumey 1998; Davey Smith 2000). Many animal studies have highlighted the perpetuation of both size at birth and subsequent growth across generations; this may have important nutritional implications especially in the developing world. Further research will assist assessment of how and when to optimally target interventions to cost-effectively improve health ocio-economic conditions throughout the life course shape adult health and disease risk. This because health-damaging exposures or health-enhancing opportunities are socially patterned, and because an individual's response, which may modify their impact or alter the risk of future exposures, will be powerfully affected by their social and economic experience(Kuh et al, 1997). The strength of the relationships between adult disease and socio-economic circumstances at different life stages can hus provide clues to the underlying aetiological processes(Davey Smith et al, 1998). A life course approach is being used in research on social inequalities in health, to investigate how experiences PAGEFOUR
A LIFECOURSE APPROACH TO HEALTH PAGEFOUR A life course approach to health A life course approach emphasises a temporal and social perspective, looking back across an individual’s or a cohort’s life experiences or across generations for clues to current patterns of health and disease, whilst recognising that both past and present experiences are shaped by the wider social, economic and cultural context. In epidemiology, a life course approach is being used to study the physical and social hazards during gestation, childhood, adolescence, young adulthood and midlife that affect chronic disease risk and health outcomes in later life. It aims to identify the underlying biological, behavioural and psychosocial processes that operate across the life span (Kuh and Ben-Shlomo, 1997). A life course approach incorporates, but is broader than, ‘the fetal origins hypothesis’ (programming) which links conditions in the intrauterine environment to the later development of adult chronic disease (Barker, 1998). Growing evidence suggests that there are critical periods of growth and development, not just in utero and early infancy but also during childhood and adolescence, when environmental exposures do more damage to health and long-term health potential than they would at other times. There is also evidence of sensitive developmental stages in childhood and adolescence when social and cognitive skills, habits, coping strategies, attitudes and values are more easily acquired than at later ages. These abilities and skills strongly influence life course trajectories with implications for health in later life. Additionally, a life course approach considers the long term health consequences of biological and social experiences in early and mid adulthood, and whether these factors simply add additional risk or act interactively with early life biological and social factors, to attenuate or exacerbate long term risks to health. Cumulative effects on later health may occur not only across an individual’s life but also across generations (Lumey 1998; Davey Smith 2000). Many animal studies have highlighted the perpetuation of both size at birth and subsequent growth across generations; this may have important nutritional implications especially in the developing world. Further research will assist assessment of how and when to optimally target interventions to cost-effectively improve health. Socio-economic conditions throughout the life course shape adult health and disease risk. This is because health-damaging exposures or health-enhancing opportunities are socially patterned, and because an individual’s response, which may modify their impact or alter the risk of future exposures, will be powerfully affected by their social and economic experience (Kuh et al, 1997). The strength of the relationships between adult disease and socio-economic circumstances at different life stages can thus provide clues to the underlying aetiological processes (Davey Smith et al, 1998 ). A life course approach is being used in research on social inequalities in health, to investigate how experiences
A LIFECOURSE APPROACH TO HEALTH and exposures at different life stages accumulate and create the social inequalities in morbidity and mortality observed in middle and old age(Davey Smith, 2000; Leon, 2000) A life course approach to adult health is not a new concept-the idea that experiences in earlier life hape adult health, was the prevailing model of public health in the first half of the twentieth century In the post war period the dominance of the adult life style model for adult chronic disease was due to the early success of cohort studies in confirming, for example, smoking as a major risk factor for lung cancer, coronary heart disease and respiratory disease, and hypertension as important for stroke and IHD. However, conventional risk factors are limited in predicting individual risk and only partially explain the striking social and geographical inequalities in the distribution of chronic disease. Since the 1980s, there has been a revival of interest in life course epidemiology in response to growing empirical evidence from the maturing birth cohort studies and the revitalisation of historical cohorts Conceptual models of the life course The simplest classification groups conceptual models of the life course under 4 headings 1 A critical period model 2 A critical period model with later effect modifiers 3 Accumulation of risk with independent and uncorrelated insults 4 Accumulation of risk with correlated insults(clustering, chains or pathways of risk) There is evidence for all four models. A critical period model is when an insult during a specific period of development has lasting or lifelong effects on the structure or function of organs, tissues and body systems. Evidence suggests that later life factors may modify this early risk(model 2) For example, studies have shown that the relationships of coronary heart disease, high blood pressure and insulin resistance with low birth weight are particularly strong for those who are overweight(see figure)(Frankel et al, 1996; Lithell et al 1996; Leon et al, 1996) In contrast, the gradual accumulation of risk models encourage researchers to study how risk factors at each life stage combine to raise disease risk. Do separate and independent insults gradually cause long-term damage to health(model 3)? Risk factors tend to cluster in socially patterned ways, for example, those living in adverse childhood social circumstances are more likely to be of low birth weight, and be exposed to poor diet, childhood infections and passive smoking. These exposures may raise the risk of adult respiratory disease, perhaps through chains of risk or pathways over time where one adverse(or protective) experience will tend to lead to another adverse(protective) experience in a cumulative way(model 4). As well as the biological chains of risk linked with programming, there are social chains of risk where, for PAGEFIVE
A LIFECOURSE APPROACH TO HEALTH PAGEFIVE and exposures at different life stages accumulate and create the social inequalities in morbidity and mortality observed in middle and old age (Davey Smith, 2000; Leon, 2000). A life course approach to adult health is not a new concept – the idea that experiences in earlier life shape adult health, was the prevailing model of public health in the first half of the twentieth century. In the post war period the dominance of the adult life style model for adult chronic disease was due to the early success of cohort studies in confirming, for example, smoking as a major risk factor for lung cancer, coronary heart disease and respiratory disease, and hypertension as important for stroke and IHD. However, conventional risk factors are limited in predicting individual risk and only partially explain the striking social and geographical inequalities in the distribution of chronic disease. Since the 1980s, there has been a revival of interest in life course epidemiology in response to growing empirical evidence from the maturing birth cohort studies and the revitalisation of historical cohorts. Conceptual models of the life course The simplest classification groups conceptual models of the life course under 4 headings: 1 A critical period model 2 A critical period model with later effect modifiers 3 Accumulation of risk with independent and uncorrelated insults 4 Accumulation of risk with correlated insults (clustering, chains or pathways of risk) There is evidence for all four models. A critical period model is when an insult during a specific period of development has lasting or lifelong effects on the structure or function of organs, tissues and body systems. Evidence suggests that later life factors may modify this early risk (model 2). For example, studies have shown that the relationships of coronary heart disease, high blood pressure and insulin resistance with low birth weight are particularly strong for those who are overweight (see figure) (Frankel et al, 1996; Lithell et al 1996; Leon et al, 1996). In contrast, the gradual accumulation of risk models encourage researchers to study how risk factors at each life stage combine to raise disease risk. Do separate and independent insults gradually cause long-term damage to health (model 3)? Risk factors tend to cluster in socially patterned ways, for example, those living in adverse childhood social circumstances are more likely to be of low birth weight, and be exposed to poor diet, childhood infections and passive smoking. These exposures may raise the risk of adult respiratory disease, perhaps through chains of risk or pathways over time where one adverse (or protective) experience will tend to lead to another adverse (protective) experience in a cumulative way (model 4). As well as the biological chains of risk linked with programming, there are social chains of risk where, for