We Can Prevent Dementia
One of the stand-out scientific papers of 2020 for me has to be The Lancet Commission on Dementia prevention, intervention, and care. This paper really didn’t attract the attention it could and should have - for obvious, pandemic-related, reasons. However, it has a profound message of hope: that about forty per cent of dementia cases could be prevented or delayed by targeting 12 modifiable risk factors (see below).
This is a really wonderful message, one contrary to the usual messaging accompanying many conditions and diseases of ageing. Dementia, in particular, has terrible overtones of progressive inevitability: it is a haunting condition, with loss of memory, personality, and all that makes us human. However, dementia is not a diagnostic label: rather, it is an ‘umbrella term’ for several conditions with distinct (but sometimes overlapping) causes, and conditions that share outcomes. Alzheimer’s disease probably accounts for c. 65% of dementia cases, with other conditions (such as vascular dementia – strokes, and transient ischaemic attacks or TIAs); Parkinson’s disease; Frontotemporal dementia (FTD); and dementia with Lewy bodies) comprising most of the remaining 35% of cases.
The Alzheimer’s Association (USA) have provided a useful listing of the 10 Warning Signs of Alzheimer’s:
Memory loss that disrupts daily life
Challenges in planning or solving problems
Difficulty completing familiar tasks
Confusion with time or place
Trouble understanding visual images and spatial relationships
New problems with words in speaking or writing
Misplacing things and losing the ability to retrace steps
Decreased or poor judgment
Withdrawal from work or social activities
Changes in mood and personality
The message of hope regarding dementia
The message of hope is this: the modifiable risk factors are ones we can do something meaningful about. Cumulatively, they add up to about 40% of cases - preventing this number of cases would be an astonishing achievement. The list of modifiable risk factors for dementia are: lesser levels of education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, low social contact (loneliness) excessive alcohol consumption, traumatic brain injury, and air pollution.
The Commission has produced the following, rather beautiful, figure to capture these **modifiable** risk factors across the life-course:
The underlying beauty of the Commission’s analysis is this: these factors are modifiable.
We can fix them ahead of time by changing our behaviour. This means for about 40% of the expected cases of dementia, we can prevent them ahead of time by taking action in the here and now. Think of these behaviour changes as a safety intervention, like you might perform before going to bed - turning off lights, plugs, making sure naked flames are quenched, and the like.
Ceasing smoking might prevent 5% or so of cases (this will have knock-on effects on heart health and cancer too). One standout (for me, at least) is that detecting hearing loss in mid-life might prevent 8% or so of cases - I was unaware of this link, but it makes sense. The auditory nerve provides tonic input to the brain (think of like a tap always being on), augmenting activity in the brain. And so on through the list.
The cumulative effect is enormous: remember, there are no drugs yet available that prevent or cure the various dementias (some, like donepezil, show small, transient, benefits for cognition) - we await a cure. In the meantime, an ambitious public health regime focused on the list (education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, low social contact, excessive alcohol consumption, traumatic brain injury, air pollution) could prevent many cases of the expected 152 million cases worldwide expected by 2050 - less than 30 years away. 40% is the equivalent of about 60 million cases - an astonishing number indeed.
As the Commission itself says:
Acting now on dementia prevention, intervention, and care will vastly improve living and dying for individuals with dementia and their families, and thus society.
What are we waiting for?! We know what actions we need to take - they need to be incorporated into public health policy now - with the proviso that the effects will take time to show up. But show up they will: in terms of enhanced dignity and independent living as we age, and in terms of preventable costs to health services and decreased burdens on care-givers everywhere.
This newsletter platform supports podcasts (yay!): I am going to try this feature out, and I have lined up some authors with new books coming out this Spring for the first couple of podcasts. If it works, and if the feature is popular, then I’ll do a few more - perhaps once every month or two. I am going to do these as unadorned, rough cut, conversational pieces, and see how that works.