Select Committee on Science and Technology Written Evidence


Memorandum by the Centre for Ageing and Public Health, London School of Hygiene and Tropical Medicine

RESEARCH INTO AGEING

  1.  At the same time that concerns about the implications of an ageing population rise higher on agendas, the pace of scientific study of the biological processes underlying ageing has been accelerating. Evidence submitted by others will doubtless provide a comprehensive picture. It seems that new knowledge is adding complexity to earlier rather simple ideas based on evolutionary arguments. We may certainly hope that advances in understanding of the basis of ageing at molecular and cellular levels will lead in due course to medical interventions that prolong life and reduce age-related illness. However, the timescale for practical outcomes seems likely to be medium to long term.

  2.  In the meantime, there is a substantial research agenda that will help generate the knowledge necessary (a) to intervene more effectively in the processes that lead to age-associated impairments of physical, sensory and cognitive functions and thence disability, and loss of capability, leading to dependence; and (b) to promote active, healthy ageing. This research agenda may be outlined as follows:

    —  Age-associated diseases, where the paradigm is the world-wide effort in academia and industry to understand the basis of Alzheimer's disease, with the aim of devising rational therapeutic interventions. Other major age-associated diseases which are the subject of substantial research effort are cardiovascular disease and cancer. On the other hand, diseases which have a big an impact on quality of life in old age without being life-threatening receive less attention, in particular osteoarthritis and loss of vision through macular degeneration.

    —  "Frailty" in older people designates the consequence of the co-existence of chronic conditions which are not capable of consideration as a single pathology, and which require long term and complex interventions, including rehabilitation. There is a need to move towards more evidence-based practice, based on sound evidence derived from multidisciplinary research.

    —  Healthy ageing, the phenomenon whereby many people manage to avoid ill health in old age (at least until near to death), requires close study to identify the determinants of this desirable state of affairs and the interventions—both medical and social—that will best promote this. The psychology of normal ageing needs to be better understood, not least on account of current expectations that as people live longer they will need to continue to work longer, raising questions about the maintenance of cognitive capabilities.

    —  Modifying the physical environment to reduce the disadvantage experienced by people with disabilities. Research is needed to underpin more inclusive approaches to design, as well as to devise better assistive technologies.

    —  Modifying the social environment to foster well-being and lessen the loss of capability experienced in old age, whether on account of physical and mental disability, poverty and loneliness. This includes the design and testing of interventions to promote health through strengthening social interaction and support.

    —  Improved modelling and forecasting of different states of health of the population, including in relation to different potential family support structures—important to clarify the implications of demographic trends and identify policy options.

  3.  Much of the research outlined above is carried out through the analysis of ageing in human populations, including both demographic analysis of Census and other official data, and epidemiological surveys and trials in sample populations. Topics that can be fruitfully investigated through a population-based approach include environmental and genetic risk factors for age-related diseases, and the efficacy and effectiveness of interventions designed to ameliorate ill health, disability and social disadvantage in later life. Population-based studies are important for the investigation of differences between men and women, and those in different ethnic and socio-economic groups; variations between populations—either geographically or temporally; understanding of cohort and life course influences; and forecasting and projection.

  4.  Understanding the processes involved in human ageing and tackling age-related ill heath requires that subjects be followed over considerable periods of time in what are known as longitudinal studies. Longitudinal studies require more commitment and administrative support than do the generality of biomedical and social science research.

  5.  One important recent initiative has been the establishment of the English Longitudinal Study of Ageing, the first fieldwork for which took place in 2002, involving a sample of 12,000 people over the age of 50 whose health, economic position and quality of life are to be followed as they age. It is noteworthy that half the funding for the first five years' work is coming from the US National Institute for Aging, with the remainder from eight UK government departments. No UK Research Council is supporting this study. It will be important that the data collected in this study is made available to the research community if best value is to be obtained for the effort expended.

SUPPORT OF RESEARCH

  6.  Both ageing as a policy area and ageing research lack a single focus within government. Four research councils—MRC, ESRC, BBRC and EPSRC—are active in funding research on ageing and age-related matters. The latter three Research Councils have focused programmes of relevant research, whereas the MRC generally supports ageing research through its mainstream funding mechanisms (although it does on occasion co-fund research lead by other public bodies).

  7.  The Department of Health is active in funding relevant research through its Policy Research Programme, including work to support the National Service Framework for Older People. Other government departments also support research relevant to older people on an ad hoc basis, with the Department of Work and Pensions being prominent. European Union research funding under Framework Programme 5 supported a wide range of projects related to ageing, although this did not continue under the successor programme.

  8.  As regards voluntary sector support of ageing and related research, only "Research into Ageing", part of Help the Aged, addresses the range of biomedical opportunities, although its resources are relatively modest. More substantial research funding charities support work on age-related diseases that have historically cut people down in their prime, particularly cancer and cardiovascular disease. Conditions that detract from quality of life without causing death, such as arthritis and macular degeneration, have received far less support from voluntary sector funders and their donors. The Wellcome Trust is not currently focused on ageing as a research area, although programmes such as Health Consequences of Population change support relevant projects.

  9.  There have been some recent efforts to achieve greater cohesion of UK support for ageing research. The main players have established a Funders' Forum for Research on Ageing and Older People, and in addition a National Collaboration on Ageing Research has been set up (currently the subject of a formal evaluation). No doubt these bodies will submit evidence to the Committee. Our impression is that the Forum has had modest effect at best, although a new cross-Council research programme, led by ESRC, is promised. The Collaboration seems to have had too little resource to make a significant difference.

  10.  The UK arrangements for funding research relevant to an ageing population remain fragmented and arguably unfocused. This may be contrasted with the US National Institute of Aging: The point is not so much the size of its annual budget of one billion dollars. Rather, the NIA conducts and supports an extensive program of research on all aspects of ageing, from the basic cellular and molecular changes, through the prevention and treatment of common age-related conditions, to the behavioural and social aspects of growing older, including the demographic and economic implications of an ageing society. Thus the NIA covers the research agenda that is the responsibility in the UK of all the Research Councils and the Department of Health (excepting the design and technology research of the EPSRC). In consequence, the US has a far more coherent effort in the field than does the UK.

  11.  The National Institute for Aging exists because the US organises its biomedical research around diseases, rather than around research disciplines as in the UK. It would not be sensible to suggest wholesale reorganisation of our arrangements just to improve the support of ageing research. Nevertheless, the priorities, scale and balance of research on ageing in the UK should reflect national needs and scientific potential, not administrative mechanisms and institutional boundaries for the publicly funded support of research. Under present UK arrangements, there is no assurance that this is the case, nor is there adequate vision and leadership.

  12.  We respond next to the four questions posed in the Committee's Call for Evidence concerning research co-ordination, priorities, capability and the informing of policy.

  13.  First, as made clear above, we believe there is a lack of effective coordination of research, both within the public sector and across the public and voluntary sectors.

  14.  Second, to our knowledge, neither the Funder's Forum nor the National Collaboration have attempted a priority-setting exercise involving the whole research community, although the latter has held relevant seminars and has commissioned a bibliographic mapping exercise. Moreover, the MRC is unfocused in its approach to the support of ageing research. Accordingly, there can be no confidence that the present UK support for research adequately reflects national needs and scientific potential.

  15.  Third, the answer to the question of the adequacy of research capability must follow on from the answer to the previous question about priorities. In the area of population-base studies, longitudinal approaches are important for understanding relationships linked to ageing. Such studies require long term commitment to sustain the research infrastructure and support analysis.

  16.  Fourth, as regards research informing policy, the concept of an evidenced-based approach both to medicine and public health is now received wisdom, rightly so. However, a common problem as regards policy formulation is to generate timely evidence to influence decision making, failing which decisions are taken that turn out not to be supported by the research results when these eventually emerge. Government departments can find it difficult to commission research that might challenge current policy approaches. Hence there is a need for a strategic vision and leadership in research that can anticipate future policy requirements. In principle, UK Research Councils should be capable of doing this, but for the reasons outlined above, this is not happening for ageing research at present.

WORKING ON AGEING

Population Ageing: a global challenge

  At the start of the 21st century, population ageing is an enormous challenge to the economic and social development of many countries in both developed and developing world. In 2020 the world population of elderly people will have trebled, with 700 million people aged 65 years and over. Although the highest proportions of older people in the population are currently observed in the most developed countries, the pace of demographic change in many developing countries is leading to rapid increases in the proportions and numbers of elderly people.


  Public Health imperatives that result from the ageing of the population include: the need to identify strategies and interventions to improve the health and well being of elderly people; and the need to provide and deliver good quality health care to elderly people. Until relatively recently, opportunities for improving the health of elderly people have been limited: negative images of ageing and concepts that health promotion and disease prevention in old age are not worthwhile; and, until relatively recently, neglect by the research community of common problems of old age.

  The Centre for Ageing and Public Health at LSHTM was formed in 1998 to bring together researchers across the School working in the area of ageing. Centre members come from a range of disciplines: epidemiology and statistical methods, demography, nutrition, social sciences, social policy, history, health promotion, health services research and health economics.

  The main areas of research currently undertaken by centre members include:

    —  Demographic studies including international trends in population ageing, inter-generational exchange, socio-demographic life course and trends in disability and health expectancy.

    —  Epidemiological studies on age-related eye disease (cataracts, macular degeneration).

    —  Health services research, in particular the evaluation of health screening and of patient-based outcomes such as quality of life in chronic illness in older people, and methodological work to develop and validate new measures for use with older people.

    —  Nutrition ranging from nutritional influences on survival to evaluation of supplementation

    —  Housing and environmental influences on health of older people.

  Most of this work is taking place in the UK and other developed countries but studies on nutrition and age related eye diseases are taking place in middle and low income countries. Research is funded from a variety of sources including the Medical Research Council, the Department of Health, the Economic and Science Research Council, UK Food Standards Agency, Health Technology Assessment, European Commission, Wellcome Trust UK, the British Heart Foundation, Age Concern, Pocklington Trust, Royal National Institute of the Blind. We place much emphasis on collaborations outside the School with researchers from numerous disciplines including clinical specialities especially geriatric medicine, ophthalmology, old age psychiatry; social gerontology, nutrition, housing, transport and the environment.

  Below we present some recent findings from our research and information on new studies starting up.

Demographic studies

  Understanding and disentangling the effects of demographic, socio-economic and policy change on family support both of and by older people has formed a strand of much collaborative work. The European Science Foundation network, Family support of older people: determinants and consequences led by a member of CAPH is drawing to the end of its work and will hold a concluding symposium as part of the International Sociological Association meeting in September 2004. Results show the strong influence of cultural and policy contexts on family support, rather than demographic ones alone and indeed the effects of demographic changes on potential family support are often misunderstood. Work by centre members in collaboration with demographers at LSE shows, for example, that in Britain in the next quarter century a higher proportion of elderly people are likely to have a surviving child than for any generation ever born. Projecting the implications of these trends into the future forms part of the work of an EU project in which School members are involved. Family history, family support and living arrangements are all important influences on health and health care use in later life. Work we have undertaken, for example, showed that marital status and social support in later life is strongly associated with psychological health, although factors such as smoking were more important when other domains of health were examined. Using the ONS Longitudinal Study centre members we also examined the effects of living arrangements and health of co-residents on where older people with cancer died. Among the population with cancer, as many lived alone as in the rest of the population of the same age so by 1991 half of all female cancer sufferers aged 80 and over lived alone. Compared with those living alone, older cancer sufferers who lived with a spouse who had no long term illness were two and half times as likely to die at home and twice as likely to die at home if they lived with a spouse who themselves had a long term illness. These findings have important implications for current initiatives to extend palliative care options and increase the proportion of terminally ill people able to die at home—if they so wish.

Epidemiological studies on age related eye disease

  Age related macular degeneration is the major cause of vision loss in adults in developed countries. There are two sub-types of AMD—the more severe and visually impairing neovascular type and the atrophic type. The seven country EUREYE Study found that women had higher rates of both types than men (around two-fold increase). Smoking was a strong risk factor for both types but a history of diabetes or cardiovascular disease was associated with only the neovascular type. Little is known about the prevalence of this condition in developing countries. We have completed a feasibility study in North India which found that early signs of this condition were highly prevalent in the population and the rates for late disease were at least as common as in European populations. A large study is now underway investigating risk factors for both age related macular degeneration and cataract in the Indian population with a focus on biomass cooking fuels and dietary antioxidants.

Health Services Research

  Evaluation of screening. The benefits of multidimensional assessment of older people in the community setting are controversial. Previous trials have been underpowered and inconsistent in their results. We conducted a large cluster randomised factorial trial to evaluate the benefits of different approaches to assessment and management of older people in the community. 106 general practices (from the MRC General Practice Research Framework) and 33,000 patients aged over 75 years were recruited to the trial with response rates of 78 per cent. The main results of the trial published this year found no evidence of reductions in mortality, hospital or institutional admissions from an intensive in depth geriatric assessment in general practice, nor to management by a specialist geriatric service. There were small benefits on quality of life from hospital-based outpatient geriatric management. The evidence from the trial therefore suggests that caution is required before introducing routine assessment into the care of older people. The large size of the study and wealth of health data collected has also provided opportunities for add-on studies: a nutrition and physical activity assessment, additional data collection to determine the causes of vision impairment; a nested trial of screening for vision impairment; an investigation of factors influencing winter mortality using the mortality and health and socio-economic data from the study linked to local meteorological and infectious disease information including vaccine coverage. The results from these studies are described in more detail below.

  The MRC Assessment Trial found that vision impairment was common in the older population and rose rapidly with increasing age from 10 per cent in those aged 75-84 to a quarter of those aged 85 and over. We found that over a half of vision impairment in the over 75s was due to remediable conditions: refractive error (32 per cent) or unoperated cataract (20 per cent). In 33 per cent the cause was age related macular degeneration. This suggests that screening for vision impairment should lead to better vision outcomes. However in the nested trial of vision impairment, visual acuity screening by the practice nurse only benefited a small proportion. Key explanations for the lack of effect identified were under-detection of uncorrected refractive error, only around half the recommendations for referral to an ophthalmologist resulted in referral by the general practitioners, and unwillingness by participants to self-refer to optometry services for further assessment, citing costs and lack of perceived need. These results are in agreement with other studies which have shown that despite the availability of free eyesight tests for older people, the uptake is partial, and the result is a serious burden of avoidable poor vision. We are now working on a feasibility study of a trial of optometry services in the general practice setting which may overcome the barriers identified in previous studies.

  The influenza vaccine programme in elderly people is the start of a new public health strategy of adult vaccination in the UK. Equity in the delivery of the vaccine in epidemic years and in a future pandemic is a key ethical issue. We have used data from the MRC trial not usually available to examine more precisely population factors at individual and geographical level related to influenza vaccine uptake in older people. Uptake was 48 per cent in 1997 and did not increase substantially until 2000 when the uptake was a third higher at 63 per cent, the year in which national targets and payments to practices for each vaccine given to all over 65 year olds were introduced. Influenza vaccination was also lower with poorer neighbourhoods, personal socio-economic circumstances, and support than less poor. These differentials were not explained by higher uptake in those who were married, with underlying respiratory conditions, non-smokers and those without cognitive impairment or depression.

  Although there is good randomised controlled trial evidence of the efficacy of the influenza vaccine in preventing morbidity in older people, mortality is too rare an endpoint for reduction to be well established. Further statistical methods were also developed from the MRC trial study data to assess vaccine effectiveness using observational data. Direct comparison of mortality in vaccinated and unvaccinated persons, which is the usual method, can suffer from confounding. They were avoided in favour of quantifying responses to circulating influenza in unvaccinated persons separately from vaccinated persons. A strong increase in mortality was seen in non-vaccinated in periods of high circulating influenza but in vaccinated persons there was no such association—strongly supporting an important protective effect of influenza vaccination in older people against death.

  Evaluation of patient-based outcomes in chronic illness in older people. We have undertaken several studies to evaluate patient-based outcomes in a variety of chronic illnesses in older people. For example, as a follow-up to our original study of clinical outcomes, quality of life, health service use and costs in 221 older people on dialysis (North Thames Dialysis Study), we are now examining (i) changes in QOL over time, (ii) sociodemographic, clinical and dialysis-related predictors of QOL and (iii) predictors of poor outcome. We are also undertaking work to evaluate outcomes in polymyalgia rheumatica, a disease of older people. This prospective cohort study is assessing clinical outcomes and quality of life over a one-year period in a sample of 129 older people.

  Methodological work to develop and validate new measures of outcome. Rigorous evaluation of health outcomes is the cornerstone of any successful health service. We have been been developing and validating patient-based measures of outcome (eg quality of life, symptoms, psychosocial outcomes) for use with older people. Our work with people with dementia, stroke aphasia, eye disease in India or who are in intensive care has provided the opportunity to develop innovative strategies to produce psychometrically rigorous measures for obtaining self-reports in difficult to assess populations (eg people with cognitive or sensory impairments). This work presents several new methodological challenges: How can we reliably elicit self-reports about health outcomes from people with dementia, aphasia or in intensive care instead of relying on proxy reports, which generally do not agree with people's own reports? What question format, framing and response scales are most appropriate for ensuring reliable and valid responses?

Nutrition

  For a variety of physiological, psychological and social reasons older people are nutritionally vulnerable and frequently consume diets that are poor in both quality and quantity. This vulnerability often results in macronutrient and micronutrient under-nutrition among older people, and may be related to the onset and progression of degenerative disorders in later life. We have shown that vitamin C levels in those aged 75 and over were generally low and there was a inverse association between vitamin C levels and subsequent mortality. Plasma homocysteine levels were strongly positively associated with cardiovascular mortality in this age group. The lack of association between folate levels and mortality suggests that folate status in this population may have been sufficiently adequate to remove any negative effects of deficiency.

  Polyunsaturated fatty acids, especially the omega-3 fatty acids derived from marine fish oils have been shown to be associated with a lower risk of coronary heart disease in a number of studies but there is less work on their role in other age related diseases. Recruitment is underway for OPAL (Older People and omega-3 Long-chain polyunsaturated fatty acids) which is a UK-based trial, evaluating the effect of fish oil supplementation on cognitive and retinal function in older people. We have obtained additional funding to carry out analyses on stored bloods in the EUREYE study to investigate the associations with omega-3 fatty acids and age related macular degeneration.

  There remains much uncertainty about desirable levels of Body Mass Index (BMI) in older people and the usefulness of additional or alternative measures of body fat content or distribution. In two of our studies of older people we found that, in contrast to middle aged people, BMI in old age was inversely related to subsequent mortality. In the Whitehall study, men with the highest loss or highest gain in weight between middle and old age had the highest mortality while in the MRC Assessment Trial increasing waist hip ratio was associated with increased mortality, especially in women. These results suggest that, in old age, change in weight is a more useful indicator of risk than current weight and that a preferable measure to BMI of excess fat is waist hip ratio.

  The Centre is also involved in research attempting to find cost-effective methods of preventing disease and loss of function in older people in Chile. A pilot study conducted in Santiago demonstrated that their was considerable self-targeting by older people in the uptake of a free micronutrient-dense nutritional supplement provided at health centres. The research also highlighted previously unknown manufacturing problems in ensuring the micronutrient content of the supplement which have subsequently been resolved

Housing and environmental influences on health

  The UK has a large winter excess of mortality which is greatest in relative and absolute terms in the elderly. There have been few opportunities to examine the personal factors that pre-dispose to dying in winter. Using data from the MRC Trial of Assessment we found a small excess risk for women and for those with a self-reported history of respiratory illness. There was no evidence that other existing health problems or living circumstances or socio-economic deprivation of winter death.

  The lack of socio-economic gradient in particular agrees with other studies from the UK and suggests that policies aimed at reducing winter death, such as fuel poverty relief, require reassessment in order to ensure appropriate targeting of those at risk from cold homes.

  More detailed evidence on the effect of housing on the health of the elderly population and other vulnerable groups is also emerging from a national study of the health impact of England's home energy efficiency programme. Now in its final phases, this study is quantifying the changes associated with grant-funded energy efficiency improvements on the indoor environment, and the health and well-being of low income households. It includes an assessment, based on epidemiological modelling, of the impact of the scheme on winter mortality. Early results provide encouraging evidence about a number of health benefits of energy efficiency measures.

  There is suggestive evidence that maintaining mobility is important to sustain the quality of life of older people. However, it is hard to assess which approaches are most effective. Working with colleagues at University College London and the University of Westminster, we are investigating how best to evaluate measures intended to enhance the mobilty of older and disabled people. This work is funded by the Department for Transport and originates from a workshop arranged by the Centre. A particular task is to prepare draft guidance that the Department could issue to local authorities to assist them in the design and operation of the public realm in relation to the accessibility needs of older people.

Policy relevance of our work

  Most of our research has direct policy relevance at both the national and international level and across various sectors such as health, transport and housing. Synthesizing evidence from a number of areas of public health research is particularly important for policy recommendation for older people. An example of this is an innovative project which aims to use modern health knowledge to define the requisites of healthy, community-living people aged 65+ years, and the minimal personal costs entailed. The project draws on the wide body of research from around the world that has given us consensual and generally accepted evidence on the major personal prerequisites for health and longevity in terms of nutrition, physical activity and psychosocial relations. The study, which is funded by Age Concern England, attempts to define the minimum costs for healthy living in relation to housing, diet and nutrition, physical activity, health and social care, transport, and other essentials. It should provide the first health-based assessment of required income for older people and a hence benchmark for government policy.

October 2004




 
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