What Is Known About Prevention Of Dementia?

This talk is based on the Lancet Commission Report Dementia,

Published in 2020 by a great group of well-established researchers in the field,

Led by Professor Livingston.

Let me explain one term before we start.

Risk factors.

This means that the factors that we are about to discuss may increase your risk of getting dementia later in life.

Every word in this sentence is important,

Especially the may.

You may have zero risk factors and still develop dementia,

Unfortunately.

And on the upside,

You may have multiple risk factors,

But never develop dementia.

The content of this talk is grounded in the Commission Report,

Whereby I kind of translate such a scientific report into more lay language.

Here and there,

When the authors are speculating,

Or when evidence seems flimsy,

I will insert some commentary or additional suggestions based on my expertise.

I will also highlight things that stand out to me,

For example the lack of consideration of non-pharmacological interventions as treatments.

This is highly surprising because I know some of the authors as strong advocates for considering non-pharmacological alongside,

If not even as a first treatment option before pharmacological intervention.

But it's easy to criticise from the sideline.

The enormity of this project goes beyond what I can imagine,

And I applaud the authors for their work and the honesty and clarity with which they report their findings.

The authors state in their conclusions,

Knowledge about risk factors and potential prevention,

Detection and diagnosis of dementia is improving,

Although significant gaps remain.

I could not have said it better.

Now let's dig a bit deeper into the details of the report and focus on what has been uncovered.

In this talk I would like to share just a bit about the background to the project and how it unfolded.

Mind you,

It is unfolding as we speak.

We are not yet at our final destination.

I'll describe which risk factors are associated with which phase of life,

And then I'll talk a bit in detail about each risk factor,

What is known about the association and available interventions.

I'll finish with some conclusions.

Background.

In 2020 around 50 million people lived with dementia worldwide.

In 2050 this is projected to increase to 152 million people.

The impact on society,

Healthcare systems and especially people who have dementia and their family members who often care for them is enormous.

This motivated the Commission to formulate their first report in 2017,

When nine potentially modifiable risk factors for dementia were identified.

Less education,

Hypertension,

Hearing impairment,

Smoking,

Obesity,

Depression,

Physical inactivity,

Diabetes and low social contact.

An interesting note,

In the then published graphic,

APOEE4 allele gene was included from birth,

But it has since been removed.

But this removal is not explicitly mentioned in the updated 2020 report.

From how I read it,

I think the gene was not included in the update,

Because so many people with the gene never developed dementia.

In 2020,

The Commission report now included a 12-risk-factor life course model of dementia prevention.

Together,

These 12 factors account for around 50% of dementias worldwide,

Prevented or delayed.

The additional factors included are excessive alcohol consumption,

Traumatic brain injury and air pollution.

The factors are labelled modifiable,

However some of them,

Once attained,

Can unfortunately not be reversed.

For example,

Lack of education in early life and experiencing traumatic head injury.

So the aim could be to avoid these,

However once obtained,

They are not modifiable.

One could argue that it may be helpful to counterbalance low education or head injury in the way one rehabilitates,

Or to what extent a person can and tries to keep learning throughout life.

More on this later.

Some can be targeted at society level,

For example providing good quality education to all children,

As well as reducing air pollution.

Physicians can promote the use of hearing aids,

Recognising and referring for depression treatment,

Promote a healthy lifestyle including cessation of smoking,

Limiting alcohol intake,

Maintaining a healthy weight and being physically active.

However most of these strongly rely on individual's capacity and motivation,

Willingness to implement changes in lifestyle.

Habitual behaviour,

A lack of motivation and limited time can all prevent individuals from changing.

The fact that still 60% of dementia remains unexplained does not help with motivation.

Phrased differently,

You can have zero risk factors and still develop dementia.

You can have multiple risk factors and still not develop dementia.

Maybe it helps that many of these factors are also associated with heart health,

Which makes improving on these factors a potential double plus.

Let's talk about life changes and which factors are relevant when.

The authors distinguish between early life,

Under the age of 45,

Midlife,

45 to 65 years of age and later life after 65.

For each factor I will share the percentage that represents the reduction in dementia prevalence if the risk factor would be non-existent.

In early life the only known risk factor is less education,

Which accounts for 7% of dementias.

For midlife 5 factors are unknown,

Hearing loss accounting for 8%,

The highest percentage of all risk factors,

Traumatic brain injury 3%,

Hypertension 2%,

Excessive alcohol consumption and obesity both 1%.

Obesity and hypertension reduce in later life,

Especially for people who develop dementia,

Making them an indication of sickness and not a lack of risk,

Hence they seem more relevant to establish in midlife.

At 65 plus,

Later life,

The following factors are considered to increase your risk of dementia.

Smoking with 5%,

Depression with 4%,

Social isolation 4%,

Physical activity 2%,

Air pollution 2% and diabetes 1%.

Let's talk about these factors one by one,

Following the life course as well as the impact each risk factor has.

Starting with education.

Higher childhood education levels and lifelong higher educational attainment reduce the risk of dementia.

The impact of additional education after the age of 20 seems less prone to influence brain functioning.

For this reason,

Education seems most relevant as a risk factor for dementia in early life.

The authors also write about use it or lose it,

Stating that mental activity might improve cognitive function.

A personal note from me,

Lifelong learning,

For example learning a new hobby,

Another language,

But even just taking a different route to work or home,

Stimulates the brain differently than going on autopilot.

There is no evidence to support the impact,

But it would do no harm and in addition it would introduce more mindfulness into your life.

Because when you do things differently,

They require your full attention,

As opposed to functioning on autopilot.

In terms of cognitive interventions,

The authors report no evidence for cognitive training programs to increase cognitive functioning.

Hearing impairment.

The factor with the highest population attributable factor in the report.

PAF signifies the reduction in population disease if exposure to a risk factor were reduced.

In the report it is set to zero.

So if nobody had hearing loss and or did have hearing aids,

Dementia cases would be reduced by 8%.

The WHO has set the threshold for hearing loss as 25 decibel,

And this will almost double the risk of developing dementia in later life.

In terms of interventions,

Hearing loss may result in cognitive decline through reduced cognitive stimulation.

I also have a theory that possibly it has a relationship with social isolation.

When your hearing is not good,

You may shy away from social interaction and become more isolated.

The good news is,

When using hearing aids,

The relationship with worsened cognition is not sustained.

Traumatic brain injury.

The International Classification of Diseases defines mild traumatic brain injury as concussion and severe traumatic brain injury as skull fracture,

Eudema,

Brain injury or bleeding.

Single severe traumatic brain injury results in brain changes that are seen in dementia.

The risk increases with multiple events.

Traumatic brain injury is usually caused by car,

Motorcycle or bicycle injuries,

Military exposures,

Boxing,

Horse riding and other recreational sports,

Firearms and falls.

The report then groups together factors that are related to heart health.

Firstly,

Hypertension,

A midlife factor.

Persistent midlife hypertension is associated with increased risk of late-life dementia.

Studies define hypertension as a systolic pressure of 130 or more.

In terms of interventions,

The report mentions the use of high blood pressure medications is recommended.

Then physical exercise,

A late-life factor.

Quite complex.

First of all,

Studies report mixed findings,

So some are positive and some are negative.

Also,

Physical inactivities can be a cause or a consequence of dementia.

People who experience brain changes may cease exercising.

It seems that people who have cardiovascular morbidity experience additional effects,

Including on brain health,

When they are also physically inactive.

In terms of intervention,

It is not clear when exercise should start at what point in life.

The authors state that it's never too late.

They also mention that exercise needs to be acquired and then sustained over time,

Closer to the time of risk.

No indication of what kind of exercise to do.

Only a mild recommendation that aerobic activity may have the most benefit.

Next is diabetes,

Also a late-life factor.

The authors summarize the evidence,

Saying that overall type 2 diabetes is a clear risk factor for development of future dementia.

If medications reduce this association is yet unknown.

Excessive diabetic control does not decrease the risk of dementia.

The authors go on to recommend to combine cardiovascular risk factors to better explore the relationship with developing dementia in later life.

Not much evidence is presented,

But as I mentioned earlier,

A healthy heart and a healthy brain seem to be related.

To continue with the mid-life factors,

Excessive alcohol consumption.

Drinking more than 21 units per week is associated with a higher risk of dementia.

However,

Abstaining leads to a higher risk of dementia as well.

This seems to point to moderate alcohol intake as a recommendation to prevent dementia.

Both alcohol consumption and acquired brain injury are associated with early-onset dementia,

Which means before the age of 65.

And finally for mid-life,

Obesity.

A BMI of 30 or more impacts brain health.

However,

Being overweight,

A BMI between 25 and 30 does not.

They show some promising results that weight loss leads to better cognitive functioning.

For later life,

There are 4 more factors that are not related to heart health.

Firstly smoking.

Smokers are at higher risk of developing dementia and also at higher risk of premature death,

Which kind of blurs the association between smoking and dementia,

Because many smokers will have died before they could have developed dementia.

Stopping smoking reduces the risk of dementia,

Even at an older age,

The authors conclude.

Depression in late life.

A factor with again a very complicated relationship with dementia.

Depression may be an early indicator of brain changes and the development of dementia.

Developing dementia may lead to feelings of depression.

They may co-occur.

What is cause and consequence is hard to establish.

Furthermore,

The authors present mixed evidence for antidepressants.

Non-pharmacological treatments,

Like talking or running therapy,

Are not mentioned in the 2020 report when describing depression interventions.

Social life.

Having social activities and a social life seems to have a protective function for later life dementia.

The authors mention a large role for marital status,

Stating that married people are more socially active.

Those never married and those who have been widowed seem to be at higher risk of dementia.

They do not describe any interventions to improve social life.

And lastly they mention air pollution,

With very little evidence.

All the associations are just based on one study.

Two factors are currently under scrutiny to be added to the model.

Firstly,

Sleep.

Both too little and too much sleep may be risk factors.

And again,

Only pharmacological treatments are included,

Hence not recommended.

They are even labelled as hazardous.

And secondly,

Diet.

Again this seems most relevant in people who have cardiovascular risk factors.

The authors write a little bit about the Mediterranean diet with more vegetables and nuts and less meat and less saturated fat.

This brings me to my conclusions.

To once more repeat the authors' conclusions.

Knowledge about risk factors and potential prevention,

Detection and diagnosis of dementia is improving,

Although significant gaps remain.

Indeed,

Explaining 40% of dementia is fantastic,

And a huge improvement from where we stood a mere 6 years ago.

Where all that was known was a relationship of dementia with age,

The older you are,

The larger the risk,

Gender,

Females are more prone to develop dementia.

This report finally shed some light on what may underlie this.

Both less education and a higher age,

Slash more prone to end up living alone as male spouse die younger,

A family history and Down syndrome.

None of these factors are modifiable.

You have them or are them or not.

Being able to list 12 preventable or modifiable lifestyle factors that are associated with a risk of dementia is a huge leap forward.

However,

The details,

The underlying pathways are yet to be explored.

Again,

This is not a criticism of the report.

This is our reality when dealing with dementia.

It is highly complex,

Factors are closely interrelated and effects are hard to separate.

So we stare the truth in the eyes and admit that for 60% of dementia the cause is unknown.

We do not yet know what other factors may contribute and to what amount.

The work continues.

Here are some recommendations formulated by the authors with some comments from me.

1.

Be ambitious about prevention.

It is about policy and individuals.

It begins early in life and continues throughout life.

It is never too early or too late to develop different habits,

The authors state.

They mention public health programs,

Population strategies and identification of groups at risk.

I would also like to include individuals' responsibility and attempts to increase knowledge,

Self-efficacy and empowerment.

Health courses not restricted to dementia,

But definitely with a separate mental health section should be in the standard curriculum.

Not only do people and children need to know how to stay healthy,

But also how to compose themselves.

Think about courses in logical reasoning,

Discussion and debating,

Asking critical questions.

Anything to make individuals partners in their process to improve and maintain health and a good quality of life.

And 2.

They state some specific actions for each risk factor.

I'll start with the one that I find the most promising because of the size of the impact,

That 8%,

And a relatively easy intervention.

The use of hearing aids and or the protection of ears from excessive noise exposure.

Secondly,

Avoid smoking uptake or stop smoking at any time in your life.

Limit your alcohol intake to less than 21 units per week.

For governments,

To provide all children with primary and secondary education.

From around the age of 40,

Maintain systolic blood pressure of 130 or less.

The authors recommend antihypertensive medication.

I would like to add other,

Non-medicinal factors that can impact blood pressure,

Like diet,

Physical activity,

Reducing stress levels,

For example by meditating or doing yoga or Qigong.

We are on Insight Timer,

Right?

Reduce obesity and the linked condition of diabetes.

The only specific recommendation the authors make is to sustain physical activity throughout life.

It is never too late to start.

Reduce your exposure to air pollution and second-hand tobacco smoke.

Easier said than done.

Often we live where we live,

With no chance of moving elsewhere.

The evidence for this factor is very limited,

So I would not comment more in the hope that more evidence will emerge in coming years.

Next,

Prevent head injury.

I'm pretty sure that this is not something that people seek out.

How would we prevent accidents?

And finally,

Address other putative risk factors,

Such as sleep,

Through lifestyle interventions.

But again,

No details are provided.

I noticed that the recommendations in the report are targeted at healthcare professionals,

And they are mainly medicinal.

There is a short section for those with dementia,

But again focusing on how to support people who have dementia.

This section includes the following recommendation.

Provide holistic post-diagnosis care,

Manage neuropsychiatric symptoms,

And support family cares.

Again,

I could not agree more.

I will finish this talk to conclude what you as an individual can do to reduce your risk of dementia in later life.

Firstly my take on the Commission Report.

This report is the start of something great,

A road not yet travelled with many obstacles,

Roadblocks,

Winding roads,

Erosion,

The lot.

This work will continue for decades if not centuries.

Based on the evidence presented in this report,

I would recommend to individuals.

1.

Get your ears checked and do not hesitate to either protect the ears when they are still in great shape,

Or to take up the use of hearing aids.

2.

Stop or never start smoking.

This goes above and beyond just the issue of dementia.

And 3.

Limit your alcohol consumption.

Even if you only drink sometimes,

Understand that binge drinking can be just as harmful as frequently drinking just a little bit too much.

So ears,

Cigarettes and drinks.

The other factors are sometimes not or no longer in our hands,

Education,

Pollution,

Or deserve more study,

Either about the relation with dementia or how to treat and modify them.

The motto of a healthy heart is a healthy brain resonates with me.

The heart supplies the brain with blood,

So intuitively this makes sense.

Being physically active,

Maintaining a healthy weight,

Avoiding high blood pressure,

Cardiovascular disease and diabetes.

If your physician does not know much about dementia,

Ask about improving your heart health.

And keep an eye on research developments in this area.

Alzheimer's Australia had a wonderful campaign about a decade ago.

Stay active,

Socially,

Cognitively and physically.

This is wonderful advice.

As mentioned throughout this talk,

There are no guarantees.

So I would like to add,

Work within your own boundaries.

Do not force yourself and find adaptations and activities that suit you,

That you enjoy.

Do not take on too much,

One step at a time.

Thank you for joining me for this talk.

I hope it has been helpful.

Namaste