Research on Health and Ageing using English Longitudinal Study of Ageing (ELSA)

The English Longitudinal Study of Ageing (ELSA) is a well-established, on-going, multi-disciplinary cohort study involving a collaboration between University College London (UCL), the Institute for Fiscal Studies (IFS), the University of Manchester (UoM), and National Centre for Social Research (NatCen). However, this data sharing agreement covers only the initial transfer of data that happened back in 2016 and the ongoing processing of data by UCL for the purposes described under this DSA. All other collaborators will enter into separate agreement with NHS-Digital if they wish to access the data at their own institutions (currently IFS have a DSA in place but UoM do not). So for this DSA UCL and NatCenx are joint data controllers. No more data needs to be transferred from NatCen under this extension. All researchers access the data at UCL and are employed by UCL.

There are no data processors under this agreement.

The legal basis for the data processing by both UCL and NatCen is Article 6 (1) (f) Legitimate interest. As research organisations we have an interest in understanding ageing and how that affects individuals, society and the economy. There is also a wider public benefit because our research aims to help people in government, charities, academics and other influential people, when thinking about planning services which affect people aged 50 and over. Additionally, the lawful basis for processing special category linked health data (Article 9(2)(j) is ‘scientific research purposes’. There is no other reasonable way to achieve this purpose and our participants are informed of this legal basis and so would reasonably expect their data to be used in this way and they are unlikely to come to any harm from the processing. A legitimate interest assessment has been carried out.

The data that we are processing under this agreement is the data that is being held under NIC-311182 but with directly identifying information removed. This means that NHS number and names and addresses have been removed. All other fields are necessary to carry out the research relevant to this purpose. UCL has a long track record in using these data for a variety of research project (see outputs section) and as such understands which variables are needed and which are not. The variable specification supplied under NIC-311182 was informed by UCL researchers and as such the entire set of variables supplied contained only those that are necessary for the purpose described under this DSA.

Since its inception in 2002 it has provided valuable insights into a range of social, health and economic issues. The data subjects are individuals aged 50 or over and their partners who have agreed to be interviewed after being sent an advance letter or who have been interviewed previously. Respondents were recruited from various years of the Health Survey for England. Traditionally, data have been collected biennially face-to-face via interview and clinical examination. Each biennial data collection is referred to as a “wave”. Wave one data collection took place in the period 2002-03, wave 2 in 2004-05 and so on. The 2020 wave 10 was disrupted by COVID-19 and is currently in the field. Each wave, all individuals who previously took part are re-contacted to ask if they would be willing to be re-interviewed. All those who agree take part along with any new partners they may have. Additionally, in waves 3, 4, 6, 7 and 9 (also planned for wave 10), the sample has been “refreshed” with new members to avoid small sample sizes at the younger ages. In each wave, participants are reminded of the permission they gave for data linkage and are given the opportunity to revoke that permission. While this approach has been very useful and will continue, linkage of study members in ELSA to routinely-collected data offers not only additional rich, complementary information about their health which cannot be gathered using these methods (e.g., valid data on diagnosis and prognosis of common chronic diseases such as cancer and depression) but, crucially, data which come at no burden to the study members. Participants are invited to re-consent every 2 years when study members are re-interviewed.

The Department of Epidemiology and Public Health at University College London (UCL) require linked pseudonymised Hospital Episode Statistics (Admitted Patient Care, Outpatient, Critical Care and Accident & Emergency) and Cancer registration data as part of their research obligations as part of the ELSA research group. This agreement will permit NatCen (under NIC-311182-N0L1Y subject to an active DSA and supporting purpose) to share pseudonymised linked HES, and Cancer data in order for UCL (under this agreement) to carry out their obligations.

The requested data will be used for a programme of research on health and ageing in England. This is a long-standing and on-going programme of work which aims to improve understanding of the ageing process, and how the use of health care affects this ageing process and the evolution of health over the lifecycle.

Linking NHS Digital data with ELSA will allow UCL to combine detailed information on health outcomes; the use of hospital services; the quality of health care and the identification of trends in health that will impact on future demands for health care with wider characteristics of the elderly population. The proposed linkage of ELSA to administrative health data will provide novel data for research on ageing in England. Existing studies on ageing, and in particular the use of health and social care services of individuals as they age, has been restricted by extremely limited data on the use of these services. Studies on the evolution of health at older ages using administrative health records has also been limited by a lack of information on the socio-economic and wider health characteristics of individual. Linking the data together therefore provides a rich dataset which enables research in this crucial policy area.

The work will be carried out by researchers at UCL and is funded by research grants from the National Institute on Aging in the USA, and the Economic and Research Council in the UK. There is a team at UCL who carry out research on ELSA as well as manage the study, and this is funded by the MRC, Cancer Research UK and other funders as well as by NIA and the ESRC. This request is to allow that team to carry out this research.

These new data will be used to continue UCL’s programme of research on ageing and health in England which aims to improve understanding of the ageing process, including predictors of various age-related disease diagnoses (e.g., heart disease, stroke, specific cancers, depression, dementia), and how health and the use of health care affect that ageing process. This will have value in planning services, predicting future needs, estimating the costs of care, and understanding the impact of various ageing states on individuals and their families. All analyses will use de-identified data.

Specifically, the data will improve understanding of:

1) Variation in hospital use across individuals with different individual and family characteristics, particularly at the end of life, providing a new understanding of the extent to which spending is efficiently allocated across different types of people.

2) The relationship between social care provision and hospital use, in particular the extent to which lack of social care availability may increase use of hospital care either through more entry into hospital or delayed exit.

3) Social inequalities in health among older people in England, and the relationship between these inequalities and other social characteristics, quality of care, and disability. This work is important for future planning of health care provision.

4) New funding from the National Institute on Aging has charged UCL explicitly to model the incidence of dementia in the ELSA population, and this will be greatly facilitated by the availability of hospital care statistics. At present, UCL’s estimates of dementia incidence and prevalence are based on cognitive tests and ratings from relatives and carers. Having information about the use of hospital services by ELSA participants with dementia and cognitive impairment will strengthen the evidence base and provide a platform for more detailed analyses of the determinants and consequences of dementia. UCL will also be able to fulfil the mandate from the National Institute on Aging to provide analyses that can be used to compare dementia rates in the UK and USA.

UCL will use the pseudonymised linked data for research on ageing to understand what factors influence survival, and whether attrition from the repeated measures in the study has happened because of drop-out or because they died.

Another objective of this research project is to compare the risk of mortality following the onset of different health conditions across demographic and socioeconomic groups within the older population in England, and between similar groups in England and the USA.

1) The cancer registration data is specifically required for projects funded by Cancer Research UK. These will address the following issues: The relationship between body weight, changes in body weight, and cancer incidence among older people.

2) The impact of cancer diagnosis on health behaviours and quality of life. Up to now, UCL have based these analyses on self-reported diagnoses (Br J Cancer, 2013; Psycho-Oncology, 2016). But registry data will allow these issues to be investigated with greater precision.

3) The association between bowel cancer screening (measured in ELSA since 2012) and cancer incidence.

4) The relationship between psychosocial factors (depression, social isolation, cognitive function) and cancer incidence.

Other projects that will take place as part of this programme of work are:

(1) To examine how the pattern of hospital care use changes in the final year(s) of life, and to examine whether it is proximity to death, as opposed to age, that determines healthcare utilisation (controlling for other characteristics captured in the ELSA data).

(2) To compare the risk of survival following the onset of different health conditions across demographic and socioeconomic groups within the older population in England, and between similar groups in England. UCL will use the information on cause of death to find out who has had an onset of a condition prior to their death, so that UCL can work out the probability of survival among those who experience (e.g.) a heart attack. UCL have missing survey information on those who die before they are able to report a new onset, and the cause of death information allows UCL to fill in the gap.

The requested data would be used solely for research purposes, in accordance with the research aims stated above. UCL would model the use of NHS-funded inpatient services (provided by HES) by individuals with similar underlying health needs, but who differ in other, non-need based characteristics (provided by ELSA). UCL then model the relationship between receipt of social care and hospital admissions to examine whether cuts in social care are likely to increase probability of hospital admission.

As specified, ELSA consist of NatCen, IFS, UCL, and UoM working in collaboration. NatCen are the holders of the ELSA cohort and thus only NatCen hold the identifiable data in association with this cohort. IFS, UCL and UoM only have access to a pseudonymised version of the main ELSA data (i.e. ELSA data not linked with NHS digital data) with only the pseudonymised study ID as a form of identifier. For the purpose of this agreement UCL will obtain pseudonymised data from NatCen directly.

The data shared by NatCen contains both ELSA data (pseudonymised) and data provided by NHS Digital under NIC-311182-N0L1Y (also pseudonymised). The NHS Digital data shared will be restricted to the fields and pseudonymisation specified in this agreement and in that of NatCens agreement under NIC-311182-N0L1Y. Note that no more data needs to be shared under this extension. All data that is needed for this purpose has already been shared. This agreement is simply to extend the time period on the DSA.

The data received from NHS Digital will be converted by NatCen into a pseudonymised format before onward sharing to UCL by removing identifying data. Date and Birth, Date of Death, Date of Inquest, and Date of Registration will be converted to MM/YYYY format. Cancer registration number will be downgraded to the first 6 digits. Only pseudonymised data will be shared with UCL and UCL may only receive, process and retain the data with an active NHS Digital Data Sharing Agreement in place.

All organisations party to this agreement must comply with the Data Sharing Framework Contract requirements, including those regarding the use (and purposes of that use) by “Personnel” (as defined within the Data Sharing Framework Contract ie: employees, agents and contractors of the Data Recipient who may have access to that data).

No data will be shared outside of the ELSA research group. Each organisation requesting access to the data will be required to hold an active agreement with NHS Digital.

All persons accessing the data are direct employees of UCL, and who are named ELSA collaborators.

The Data will only be used for the purposes described in this agreement.

UCL do not require identifiable data nor will they attempt to re-identify this data. The data will not be linked to any other dataset.

The UCL team require the earliest data (from 1997/98 or as far back as possible) on all admissions, outpatient appointments, critical care and A&E attendances at NHS hospitals in England. The youngest ELSA cohorts were born in the 1950’s and that coupled with information UCL have about early life experiences allows UCL to predict both the risks and consequences of hospital usage over time and across much of the life course. The statistical power of the research will be greatly enhanced by capturing as many years of hospital usage as possible and will enable the UCL team to carry out their proposed research in a statistically robust manner.

When turning the supplied data to outputs UCL will be doing the following:

(1) Produce hospital utilization measures

(2) Produce death outcome measures

(3) Produce cause of death measures

(4) Use (1), (2) and (3) to run regressions, correlations and produce descriptive statistics to further our understanding of the relationship between these and the ageing process.

(5) Create indicators of hospital admissions at the local authority level

The number of scientific, peer-reviewed journal articles using ELSA data is substantial (almost 1,000 at time of writing), and ELSA researchers have given numerous presentations, talks and seminars at government meetings, academic conferences, and policy workshops. Other outputs will include presentations at academic conferences and presentations to policy makers. Presentations with policymakers will focus on disseminating results, and helping to inform the government departments who are involved in planning and delivering NHS care to older people. All outputs will only report large sample aggregate statistics and regression outputs and small numbers will be suppressed in line with the HES analysis guide. No individual or episode level data will ever be published.

Two types of written output are expected:

(i) Articles submitted to peer-reviewed journals. Previous results have been published in high impact general medical and scientific journals (Lancet, British Medical Journal, Journal of the American Medical Association, Proceedings of the National Academy of Sciences USA), and in specialist journals in epidemiology, public health, and social science.

(ii) Non-technical research summaries which will be press-released and target policy makers, such as the Department of Health and Social Care and NHS England.

The combined pressures of a rapidly ageing population, the COVID-19 pandemic and a prolonged period of public spending austerity has resulted in unprecedented pressures on NHS services, which will only increase over the coming years. The UK population aged 65 and over is expected to increase by almost 40% over the next 20 years. And although life expectancy has increased, a greater proportion of those years will be spent living with a disability. The greater number of older people means that dementia cases are expected to increase by 75% over the next 30 years. Understanding how to meet these additional demands with fewer resources is therefore a key challenge for health and social care policymakers and practitioners. The importance of this challenge is reflected in the various policy and practice debates in recent years, for example the Better Care Fund the Dilnot Commission and initiatives such as the Quality Innovation Productivity Prevention (QIPP) programme, culminating in the recent plan for adult social care charging reform. It also highlights the importance of prevention rather than cure, and the crucial role played by lifestyle and behaviour in more effective prevention.

Existing work on ELSA has been used to inform policy makers including NHS Improvement, NHS England, the Department of Health and Social Care, the Department for Transport, the Department for Work and Pensions, the Department for Levelling Up, Housing and Communities, the Cabinet Office and representatives from Clinical Commissioning Groups . This academic approach helps to understand the impacts of former policy and guides improvements to the existing health and social care system. The DHSC has noted that they have “have no doubt that the linkage of the Hospital Episode Statistic with survey data from the English Longitudinal Study of Ageing will be a valuable source of information in understanding the variation of health care use across individual with similar medical needs but different characteristics”.

The data linkage between HES and Cancer Registration data with ELSA provides an important contribution to this debate. ELSA has high quality data on the social circumstances of a large representative sample of older people living in England, very precise economic data on wealth and income, a broad range of psychological factors, information about health and disability, lifestyle factors relevant to health including physical activity, diet and cancer screening participation, objective measures of cognitive function, physical capacity, health-related biomarkers, genetic data, and more recently, COVID-19. A particular strength of ELSA is that it is a longitudinal study involving data collection every two years since 2002. This allows trajectories of social, economic, psychological and biological processes to be tracked over prolonged periods.

The linkage provides detailed information on the characteristics of individuals who use health and social care services and who experience major health problems. This enables detailed analyses of who uses these services, and helps to identify any spillovers in the use of health and social care (e.g. whether cuts in social care spending have negative impacts on NHS services). In particular, the ability to follow the same individuals over an extended period of time provides information on how needs for (and use of) health and social care have changed over across cohorts. This contributes directly to an important debate over the size of additional pressures on services as a result of an ageing population (e.g. does ‘healthy’ ageing lead to increased health spending?). UCL is also able to strengthen the evidence base for the importance of maintenance of healthy lifestyles into older ages. Some people believe that once they have reached 60 or 65 years old, then sustained physical activity, healthy dietary choices and other lifestyle factors no longer matter because they have already done their damage. UCL research with other datasets indicates this is not the case, but ELSA can provide even more convincing evidence because of its representative sample and long follow-up, to help drive the prevention agenda in order to reduce health and social care costs among the elderly.

1) Linked data were used in the component of work led by UCL for the report commissioned by the Centre for Ageing Better, ‘Boom and bust?’ published in November 2021, which found that people in their 50s and 60s today face worse circumstances than the cohort before them, with 1 in 5 people in this age group likely to face multiple, long-term problems: https://www.ageing-better.org.uk/sites/default/files/2021-11/boom-and-bust-report-the-last-baby-boomers.pdf. Hospital data were used as a key event and the impact that being admitted to hospital had on mental health, wellbeing and financial circumstances was explored longitudinally (from 2002 to 2018/2019) in ELSA. The resulting report showed that across many key aspects of life such as health, work, housing, finances, family make-up and social lives, people in their 50s and 60s today are facing worse circumstances than people who were at the same age in 2002. The report also highlighted that people from minority ethnic backgrounds are at particular risk of experiencing an old age marred by multiple, chronic problems such as poor health, poor finances and poor social connections. A documentary was produced to accompany this report: https://www.youtube.com/watch?v=SYYD19b1vPE.

The evidence presented in this report will be of key importance for national and local policy makers and practitioners who are aiming to improve experiences and outcomes for people as they approach later life and in later life. This report also sets out a series of recommendations for government.” The most relevant recommendation for health and social care policy was:

“The government’s manifesto commitment to deliver five extra years of healthy life expectancy is badly off track. Investing in preventative public health measures to reduce risk behaviours in mid-life must be a top priority for the Office for Health Improvement and Disparities if the government is to keep its promise.

2) A recent NIHR Alert covering research from ELSA was published as part of a Collection on loneliness, published in September 2021: https://evidence.nihr.ac.uk/collection/how-can-we-reduce-the-toll-of-loneliness-in-older-adults/. This work drew on published analyses that used the linked data to highlight the impact of loneliness on older people’s health and wellbeing and the need for interventions that reduce the toll of loneliness among older people. A podcast episode was also produced as part of this Collection which the ELSA PI, Andrew Steptoe, took part in: https://open.spotify.com/episode/4WJka6Yt9gl4Xl7CW6qXwD.

3) Several UCL-led analyses using the linked data were also cited in the WHO scoping review: What is the evidence on the role of the arts in improving health and well-being? (2019) https://www.euro.who.int/en/publications/abstracts/what-is-the-evidence-on-the-role-of-the-arts-in-improving-health-and-well-being-a-scoping-review-2019 . This review led to the establishment of the WHO Collaborating Centre for Arts & Health at UCL in 2021. ELSA linked data is one of the key sources contributing to the evidence base for and monitoring of social prescribing in England.