This year the World Health Organization published guidance on ways to reduce risk of dementia and cognitive decline (WHO | Risk reduction of cognitive decline and dementia, 2019) which was highlighted in the World Alzheimer’s Report 2014.
Recently Alzheimers New Zealand and the New Zealand Dementia Cooperative produced a draft action plan (Improving Dementia Services in New Zealand: Draft New Zealand Dementia Plan 2020 to 2023, 2019) setting out the priorities for dementia risk reduction.
There has been a prolific amount of research identifying ways to reduce risk. However, much of the focus on risk reduction is on pre dementia/cognitive decline. Yet there is work that can be done once someone develops dementia.
Risk reduction for dementia may be considered on three levels:
Level 1 (primary): Interventions targeted before symptoms present.
Level 2 (secondary): Interventions targeted at individuals who develop mild cognitive impairment (MCI).
Level 3 (tertiary): Interventions targeted at individuals living with dementia and their carers. These interventions aim to slow the progression of the disease and potentially alleviate some of the burden, enabling people to maximise strengths.
A landmark Lancet Commission (Livingston et al., 2017) published a paper identifying nine major risk factors. Midlife ‘Hearing loss’ now features as a modifiable risk factor, together with the importance of building cognitive reserve, managing hypertension, obesity and diabetes, smoking, depression, social isolation and physical inactivity.
Based upon modelling, the authors suggest approximately 35 percent of all dementia may be attributable to a combination of these nine factors. However, the authors highlight that a limitation with the model used is the assumption of a causal relationship between the risk factor and dementia, which without undertaking randomised control studies can be difficult to show.
It is suggested midlife hearing loss may be a risk factor for developing dementia (9%), which was a surprise to many. It is unclear what the relationship is between hearing and the development of dementia and whether correction by hearing aids will delay the onset of dementia.
However, this report ignores the possibility that hearing loss might be a consequence of preclinical neurodegeneration rather than a cause. There is no evidence showing higher rates of dementia in the deaf community (Kulmala, Ngandu and Kivipelto, 2018). Whilst unclear, it is advisable to have regular hearing checks and support to use correction aids. Screening for hearing loss should be carried out regularly.
The debate continues as to whether depression is a cause, or consequence, of dementia. Depression can be characterised with cognitive challenges such as poor memory and is therefore difficult to detect and treat when someone develops dementia due to overlapping symptoms.
Cognitive reserve, building capacity in the brain, might help protect the brain when someone develops dementia. Over the course of a life, this is about having good quality education from a young age and continuing to learn and develop interests that may support your brain to flourish. Learning new things that challenge is the key, rather than doing the same things repeatedly.
Smoking is a risk factor for a number of physical problems such as cancer, heart disease and respiratory disorders. Cigarettes have a number of toxins and it is not clear which are responsible for the damage to the brain. However, research has shown that smoking can lead to a risk of cognitive impairment and dementia. These studies show an association between tobacco smoking (including in mid-life) and dementia, or cognitive decline, in later life (Livingstone, 2017).
Evidence suggests diabetes can cause cognitive decline (Yaffe et al., 2012) and diabetes (type 2) is a risk factor for dementia. However, the mechanism in which this happens is still unknown. With more than 257,000 people living with diabetes in New Zealand, this is an area of concern, particularly among certain communities where the risk is higher. Obesity may be related to prediabetes, so diet and exercise are key considerations in prevention strategies.
Whilst obesity is a risk factor for dementia in midlife, some evidence suggests putting on weight in later life may be a protective factor for all causes of mortality (Flicker et al., 2010). As diets vary between ethnic groups, particular groups may be more at risk
Hypertension is the medical term for high blood pressure. People who experience high blood pressure in their midlife may be at increased risk of developing dementia. Hypertension may be caused by lifestyle including poor diet but can be hereditary.
Lifestyle changes over time now mean many people live more sedentary lives. Physical inactivity is a risk factor for dementia. Exercise impacts on hypertension, high cholesterol, insulin resistance, immune system function, anti-inflammatory properties, and increasing brain-derived neurotrophic factors (BDNF). BDNF, in short, is a protein that can accelerate brain growth.
Social isolation is used to describe the absence of social contact, whereas loneliness is the dissatisfaction with the quality and/or quantity of social relationships. Loneliness is a subjective experience and is a risk factor for dementia and is also associated with depression.
Once someone develops a mild cognitive impairment, there may be strategies available as there are a number of mechanisms that may impact on brain function causing cognitive decline.
A small number of case studies have recorded some success in reversing cognitive decline (James et al., 2019) and suggested that in taking a targeted personalised medicine approach, cognitive impairment may be reversed by identifying the cause (Chalfont et al., 2019).
The latter study included one case study in New Zealand. Factors included oxidative stress, gut dysbiosis, stress, chronic fatigue, inflammation, nutritional deficiencies, prescription medication, mitochondrial dysfunction, and hormone imbalance.
However, there is much academic debate about reversable cognitive impairment and dementia. Dementia, by definition, is a progressive condition that cannot be reversed and therefore cognitive impairment attributed to dementia is thought not to be able to reversed.
There is a growing body of literature relating to functional cognitive disorders “which is a terminology suggested to denote patients who present with memory complaints but in whom no underlying cognitive disorder is found” (Bharambe and Larner, 2018).
When someone develops dementia, there is much that can be done. As dementia educators, we work with frontline care staff on strategies supporting people to maximise their potential, which includes enabling people to stay in control as much as they are able.
This could be making changes to the social and physical environment and/or working with people to retain skills that may have been lost. This area of work may not be viewed as risk reduction in the traditional sense, but it plays a fundamental role.
Some examples of interventions at Level 3 that may alleviate the burden on the disease, and maximise on strengths might include:
- timely diagnosis
- cognitive stimulation therapy
- cognitive rehabilitation
- environment adaptations
- assistive technologies
- communication, engagement and person-centred care
- nutritional interventions
- improving access, and engagement with nature
- considering impacts of co-morbidity on self-management and care and support
- medication (moderate effect)
- carer support, education and CBT
- sensory stimulation
- optimal end-of-life care
- high-intensity exercise
- proactive strategies to reduce the harm of abuse (including unnecessary restraint)
- optimising hearing and sight loss.
The Draft New Zealand Dementia Plan highlights a need for workforce education. However, to address risk reduction, this needs to be embedded across pre- and post-dementia, considering Levels 1–3. This needs particular consideration when services are working with at-risk groups, including those with intellectual disabilities and/or mental health challenges.
Risk reduction not only needs to feature in core training but should also be embedded into daily service provision. Many care and support service personnel are already working with individuals that have mild cognitive impairment and/or individuals experiencing depression. As already noted, depression may be a risk factor for the development of dementia (Diniz et al., 2013)
Specific targeted risk reduction strategies need to be implemented for minority communities, some of which may be more at risk of specific forms of dementia, where there may also be delays in timely diagnosis. Some research suggests that Māori and Pacific presented to a New Zealand memory service at a younger age than New Zealand Europeans, and Pacific peoples presented with more advanced dementia (Cullum et al., 2018)
Accessible information needs to be available to the general population on risk factors and prevention strategies. Health literacy continues to be a challenge in diverse communities and accessible information need to be provided to family/whānau. Health checks for diabetes screening, weight management and hearing checks need to be part of the risk reduction agenda.
Proactive policies need funding, including provision being made available to tackle social isolation in dementia. Multi-model interventions are likely to be most effective, and integrated working between agencies is essential to achieve these outcomes. Commissioners of services need to consider whether services properly understand their role within risk reduction.
Finally, there needs to be a focus on care (Level 3) and faith in the idea that progressive care and support that is inclusive, promotes self-determination and addresses loneliness are, in fact, risk-reduction enablers.
Author: Caroline Bartle Dip SW, BA Hons, MBA, Pg Dip Dementia Studies, FRSA, is the CEO of 3SpiritUK Training & Consultancy. Visit www.3spirituk.com.