Nearly half of all dementia cases worldwide could be prevented or delayed by addressing 14 modifiable risk factors, according to the Lancet Commission, which identifies priorities for global health.
Recently, it added vision loss and high LDL cholesterol to the dozen risk factors it had highlighted in a 2020 report that are, theoretically at least, within society’s control.
What should we prioritise if trying to increase our odds of maintaining good brain health? Exercising in midlife is hugely important, says geriatrician Dr Seán Kennelly, who is director of the Institute for Memory and Cognition at Tallaght University Hospital in Dublin. Second to that, he recommends social connectivity.
“That’s how we take our brain to the gym. Having to remember the last conversation we had with somebody, the connections that we have to the other person, that increases that ability.”
Day centres can be a vital source of good cognitive stimulation for older people. “Hearing is a massive risk factor. Small amounts of hearing loss in midlife can translate into a much larger risk of developing dementia in later life. Your brain will always tell you your hearing is fine but you have to go and get it checked.”
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In the same way it will tell you your eyesight is fine, because it is compensating all the time. “We wouldn’t leave the house in the morning if our brain allowed us to know all the things that probably weren’t working fine.”
Keeping up to date with vaccines is one thing that is not talked about in this context, he says, but there is really significant evidence that receiving, for example, an annual flu vaccine, and a vaccination against shingles, which should provide protection for at least seven years, is associated with a lower risk of developing dementia in later life. This is possibly linked to infections causing an increase in the amount of proteins generated.
The Mediterranean diet is highly recommended, but Dr Kennelly acknowledges it is not always easy for people to access or afford its main constituents, such as fish and a wide range of fresh fruit and vegetables, and that supporting people to make the right food choices would be a good public health initiative.
The Lancet Commission’s list of 14 modifiable risk factors are:
Early life
- 1) Less education.
Midlife
- 2) Hearing loss
- 3) High LDL cholesterol
- 4) Depression
- 5) Traumatic brain injury
- 6) Physical inactivity
- 7) Diabetes
- 8) Smoking
- 9) Hypertension
- 10) Obesity
- 11) Excessive alcohol
Late life
- 12) Social isolation
- 13) Air pollution
- 14) Visual loss