Public health, prevention, and dementia

1. Summary

Public health is concerned with interventions which seek to reduce disease burden or promote healthier behaviours across a population. In the UK, responsibility for public health sits with national public health agencies and local authorities.

With 850,000 people living with dementia in the UK by 2015, dementia represents a major public health challenge here and worldwide. At present there is no cure and limited effective treatments for dementia. However, a healthy diet,regular physical exercise, managing conditions like type 2 diabetes and high blood pressure and avoiding smoking and excessive drinking can reduce risk of developing Alzheimer's disease and vascular dementia (UK Health Forum, 2014). A clear message of 'What’s good for your heart is good for your head' is needed throughout preventative public health interventions and campaigns to improve public understanding of how people can reduce their risk of developing dementia.

There is also increasing evidence that building up cognitive reserve over life can reduce risk of developing dementia. Educational attainment, complex work, and mental and social stimulation are all important, and give rise to a secondary public health messages encouraging life-long learning – 'use it or lose it'. There is also growing evidence which suggests that mid-life depression is a probable risk factor for later dementia, and its treatment should be encouraged (Byers and Yaffe, 2011).

Those people living with dementia must have a formal diagnosis so they can plan ahead and access information, support and care (Prince et al, 2011). Public health interventions which support early diagnosis of dementia are needed; both to enable those with the condition to access support and also to better understand who is affected.

Appropriate support services and initiatives such as Dementia Friendly Communities have the potential to reduce or delay the need for more intensive acute and long term care. Public health agencies, commissioners and providers should support the development of dementia friendly communities and work closely with commissioners of community support services to ensure people affected by dementia have access to the support they need. Public health agencies should prioritise the development of the Dementia Intelligence Network to better understand the impact of the condition and to improve the sharing of data.

2. Background

Public health is concerned with interventions that reduce disease burden and promote healthy behaviours across a population. Public health differs from other forms of healthcare in that it is focussed at the population, rather than the individual, level.

A huge range of factors affect public health, including: education, poverty, access to healthcare, location and nutrition. Therefore interventions in a wide variety of contexts can potentially be beneficial to public health.

Public health interventions are often preventative, seeking to reduce the incidence (number of new cases) or impact of a disease. Prevention falls into three broad categories:

  • Primary prevention, which focuses on reducing or avoiding the occurrence of a disease.
  • Secondary prevention, which is concerned with diagnosing and treating conditions early before they cause significant ill health.
  • Tertiary prevention, which focuses on reducing negative impact of an existing disease through restoring function and reducing complications.

3. Dementia and public health

Dementia represents a major public health challenge. There will be 850,000 people with dementia in the UK in 2015 (Alzheimer's Society, 2014) and 44 million worldwide (ADI, 2013). These numbers are set to rise, with it anticipated there will be over one million people with dementia in the UK by 2021 and over two million by 2051 if no action is taken and current trends continue (Alzheimer’s Society, 2014). Dementia is progressive and at present there is no cure or practicable tool for pre-symptomatic screening at a population level. Public health must respond to rising numbers of people with dementia both in terms of interventions which may reduce prevalence of dementia and in ensuring those who develop dementia are supported to live well with it.

Alzheimer's Society believes public health has five broad roles in relation to dementia:
1) Informing people how to reduce their risk of developing dementia
2) Diagnosing dementia early
3) Supporting people to live well with the condition
4) Enabling dementia friendly communities
5) Monitoring and managing data.

4. Informing people how to reduce their risk of developing dementia

While the causes of dementia remain unclear, it is known that a good diet, regular physical exercise, proper management of type 2 diabetes and hypertension, and avoiding smoking and excessive alcohol consumption can reduce someone’s risk of developing dementia (Barnes and Yaffe, 2011, Mangialasche et al, 2012) Interventions focussing on encouraging a healthier, more active lifestyle and improved diagnosis and management of type 2 diabetes and high blood pressure would therefore reduce future incidence of dementia. While a lifelong approach to good cardiovascular health is recommended for some conditions (for example high blood pressure, blood cholesterol or BMI), a healthy lifestyle from midlife onwards is likely to be particularly effective at combating dementia (Barnes and Yaffe, 2011).

A clear message of 'What’s good for your heart is good for your head' is needed to encourage people to take steps toreduce their risk of developing dementia. Existing and future interventions public health interventions and campaigns focussing on physical exercise, alcohol, smoking or diet should include this message. People diagnosed with type 2 diabetes and hypertension should be made aware of the links to dementia in later life and encouraged to manage their conditions.

In addition to these cardiovascular approaches, psychosocial interventions such as educational attainment, complex work, and mental and social stimulation throughout life also reduce the risk of developing dementia. They are thought to do so by building up a cognitive reserve (Stern, 2012 and Meng and D’Arcy, 2012), hence ‘use it or lose it’. Growing evidence also suggests that mid-life depression is a probable risk factor for later dementia, and its recognition and treatment should be encouraged (Buyers and Yaffe, 2011).

Emerging evidence (Matthews et al, 2013 and Qui et al, 2013) suggests that the prevalence of dementia may have fallen over the past 20 years, due to efforts made to improve heart health and prevent stroke and heart attacks. However, because the greatest risk factor for dementia is age and people are on average living longer, the number of people living with dementia is still set to rise.

Furthermore, the majority of evidence addresses modifiable aspects of Alzheimer’s disease and vascular dementia. There is no evidence specifically for other dementia sub-types, such as dementia with Lewy bodies or fronto-temporal dementia.

5. Diagnosing dementia early

At present, less than half of people with dementia in the UK have a formal diagnosis. This means many people are unaware of steps they can take to manage their condition, plan for the future and access support and care. Several factors have led to this low diagnosis rate including: historical lack of diagnosis of dementia, lack of understanding by the public and healthcare professionals, and an attitude among some healthcare professionals that there is little benefit in diagnosing dementia.

Improving diagnosis rates will allow those affected to plan ahead and to access information, advice and care. Ensuring people with dementia have a diagnosis will also allow better understanding of those affected and more accurate national and local planning of services.

Improving diagnosis rates has been established as a priority in England, however there is considerable variation in performance across the country. Northern Ireland has the highest diagnosis rate of all four nations, and diagnosis rates in Wales significantly lag behind other countries. Governments in all countries should make improving diagnosis rates and reducing variability in rates a priority.

Interventions to promote timely diagnosis of dementia should involve proactive case finding and reducing waiting times from first reporting of symptoms to formal diagnosis. However, at present, there is no case for population screening for dementia. Whilst there are markers which may indicate dementia, at present these are imprecise and may lead to misdiagnosis.

6. Supporting people to live well with dementia

Early access to appropriate services has the potential to support people with dementia to remain independent for longer and reduce risks of falls and decline (Alzheimer’s Society, 2011). This could potentially reduce demand for expensive acute and long term care services whilst meeting the aspirations of people with dementia to remain independent and active in their communities. However, at present many people with dementia struggle to access support when they need it. Commissioners and public health agencies should ensure people with dementia have access to high quality community services, working with social care and healthcare commissioners and providers.

7. Enabling dementia-friendly communities

Evidence from people affected by dementia demonstrates that they want to remain part of their communities (Alzheimer’s Society, 2013). However, Alzheimer’s Society’s Building dementia friendly communities report found people with dementia did not feel part of their community and did not feel their community understood their needs.

Work to enable transport, leisure, retail and other services to have a better understanding of dementia can potentially support people with dementia to remain independent for longer. Alzheimer’s Society is leading a programme to support the development of dementia friendly communities, encouraging services and local areas to take action towards being more dementia friendly.

8. Monitoring and managing data

Public health agencies at a national level have a key role in monitoring and managing data on prevalence, diagnosis and demography of diseases. At present there is often a lack of data on dementia and poor collation of data which does exist.

Public health agencies should seek to collate existing data on dementia and encourage better and more consistent collection of data to allow better understanding of prevalence and the experience of those affected. Key to this would be the establishment of national public health observatories on dementia in each UK country, which would be beneficial both for service planning and also for supporting dementia research.

9. Public Health in England, Wales and Northern Ireland

In England, responsibility for most public health commissioning now sits with local government Directors of Public Health. A national body, Public Health England, supports the work of local government and also leads on national public health work. In Wales and Northern Ireland responsibility for Public Health commissioning sits with public health agencies who work with local health and social care commissioners.

Public Health England has recognised dementia as a major priority, both in terms of prevention and also supporting the development of dementia friendly communities. PHE are supporting a 'mission' to encourage businesses and individuals to sign up to become dementia friends. Public health agencies in Wales and Northern Ireland should follow suit and work closely with other agencies already taking action on dementia, such as the Older People Commissioner in Wales.

Locally, those responsible for public health services should ensure dementia is recognised in needs assessments and commissioning. Interventions and campaigns should focus on the areas above; helping people understand how to reduce their risk of developing dementia, supporting early diagnosis, promoting support in the community, enabling the developing of dementia friendly communities and managing data on dementia.

10. Alzheimer's Society calls for:

  • Local authorities and public health agencies should ensure that they recognise dementia as the public health challenge it is
  • Existing and future public health messaging around exercise, smoking, diet and alcohol should include messaging of 'what’s good for your heart is good for your head.'
  • Public health agencies and local authorities should promote early diagnosis of dementia.
  • Public health agencies and local authorities should work closely with other commissioners and services to ensure people with dementia have access to community support services.
  • Public health agencies and local authorities should play a leading role supporting the development of dementia friendly communities
  • Public health agencies should collate existing data and encourage better collection of data on dementia through establishing public health observatories on dementia.

11. References and further information

UK Health Forum (2014). Blackfriars Consensus on promoting brain health: Reducing risks for dementia in the population. UK Health forum: London

Byers and Yaffe (2011). Depression and risk of developing dementia. National Review of Neurology.7(6): 323-31

Prince et al. (2011). ‘World Alzheimer’s Report 2011: The benefits of early diagnosis and intervention’. Alzheimer’s Disease International: London

Alzheimer’s Society (2014). Dementia UK: The Second Edition. Alzheimer’s Society: London

The Global Impact of Dementia 2013–2050, Alzheimer’s Disease International (ADI), London. December 2013

Barnes and Yaffe (2011), The projected effect of risk factor reduction on Alzheimer’s disease prevalence. Lancet Neurology. 10 (9):819-28 Review.

Mangialasche et al. (2012). Dementia prevention: current epidemiological evidence and future perspective. Alzheimers Res Ther. 4 (1): 6

Stern (2012). Cognitive reserve in ageing and Alzheimer’s disease. Lancet Neurology. 11(11):1006-12. Review.

Meng and D’Arcy (2012). Education and dementia in the context of the cognitive reserve hypothesis: a systematic review with meta-analyses and qualitative analyses. PLoS One. 7(6):e38268. Review.

Matthews et al. (2013). A two-decade comparison of prevalence of dementia in individuals aged 65 years and older from three geographical areas of England: results of the Cognitive Function and Ageing Study I and II. Lancet. 382 (9902): 1405-12.

Qiu et al. (2013). Twenty-year changes in dementia occurrence suggest decreasing incidence in central Stockholm, Sweden. Neurology. 80(20):1888-94.

Alzheimer’s Society (2011) Support. Stay. Save. Care and support for people with dementia in their own homes. Alzheimer’s Society: London

Alzheimer’s Society (2013) Building dementia-friendly communities: A priority for everyone. Alzheimer’s Society: London

Last updated: September 2014 by Gavin Terry