New Scientist reports in its January 11th issue that, at an individual level, our chances of succumbing to dementia have decreased. This is not enough to stop the total number of people with dementia rising, but it does give us reason to re-consider previous assumptions. The article looks at two recent studies in the Lancet involving thousands of people. One study, based on survey evidence, showed that expected numbers of people with dementia were far lower than predicted taking account of the increase in the average age of the populationover a 20 year period. The other noted an increase in the cognitive ability in their mid 90’s of a group born in 1915 in comparison with a group born in 1905. The hypothesis (summed up as ‘cognitive reserve’) is that ‘intellectual activities’ create a resilience to age-related decline across brain networks. So what creates this ‘cognitive reserve’ among older people? Examples suggested include:
- playing bridge
- playing a musical instrument
- having a full social life
Backed up by good health measures (don’t smoke, exercise, watch your blood pressure and cholesterol, eat a healthy diet), there is a basis for individuals to adopt a sound preventative strategy. (As the article says “.. we do have some control over how we live”.)
Also, there are a number of promising strands of research that are looking to identify the causes of Alzheimer’s and measures to counter the disease, for example, the work by Susanne de la Monte and colleagues suggesting that Alzheimer’s might be caused by a type of brain diabetes.
When 1 in 3 of us can expect to suffer from dementia at some stage and when the number with type 2 diabetes is expected to nearly double by 2035 these might not be ‘reasons to be cheerful’ .. but they might just be reasons to suppose that this is a health and social issue that we can do more about than we thought.