The brain's ability to function can start to deteriorate as early as 45, suggests a study in the British Medical Journal.
University College London researchers found a 3.6% decline in mental reasoning in women and men aged 45-49.
They assessed the memory, vocabulary and comprehension skills of 7,000 men and women aged 45 to 70 over 10 years.
The Alzheimer's Society said research was needed into how changes in the brain could help dementia diagnoses.
Previous research had suggested that cognitive decline does not begin much before the age of 60.
But the results of
this study show that it could in fact begin in middle age.
This is important, the researchers say, because dementia
treatments are more likely to work at the time when individuals start to
experience mental impairment.
The UCL researchers tested the cognitive functions of 5,198
men and 2,192 women aged 45 to 70, who were all UK civil servants, from
1997 to 2007.
Individuals were tested for memory, vocabulary and aural and visual comprehension skills.
Differences in education level were taken into account.
Mid-life crisis
The results of the tests show that cognitive scores declined
in all categories except vocabulary - and there was a faster decline in
older people.
The study found a 9.6% decline in mental reasoning in men aged 65-70 and a 7.4% decline for women of the same age.
For men and women aged 45-49, there was a 3.6% decline.
Professor Archana Singh-Manoux from the Centre for Research
in Epidemiology and Population Health in France, who led the research
team at University College London, said the evidence from the study
showed that dementia involved cognitive decline over two to three
decades.
Dr Anne Corbett, Alzheimer's Society: 'There are
things people can do to reduce their chances of getting dementia later
down the line'
"We now need to look at who experiences cognitive decline more
than the average and how we stop the decline. Some level of prevention
is definitely possible.
"Rates of dementia are going to soar and health behaviours
like smoking and physical activity are linked to levels of cognitive
function.
"It's important to identify the risk factors early. If the
disease has started in an individual's 50s but we only start looking at
risk in their 60s, then how do you start separating cause and effect?
Lifestyle choices
Dr
Anne Corbett, research manager at the Alzheimer's Society, said the
study added to the debate on when cognitive decline began, but it left
some questions unanswered.
"The study does not tell us whether any of these people went
on to develop dementia, nor how feasible it would be for GPs to detect
these early changes.
"More research is now needed to help us fully understand how
measurable changes in the brain can help us improve diagnosis of
dementia."
Dr Simon Ridley, head of research at Alzheimer's Research UK,
said he wanted to see similar studies carried out in a wider population
sample.
He added: "Previous research suggests that our health in
mid-life affects our risk of dementia as we age, and these findings give
us all an extra reason to stick to our New Year's resolutions.
"Although we don't yet have a sure-fire way to prevent
dementia, we do know that simple lifestyle changes - such as eating a
healthy diet, not smoking, and keeping blood pressure and cholesterol in
check - can all reduce the risk of dementia."
Professor Lindsey
Davies, president of the Faculty of Public Health, said that people
should not wait until their bodies and minds broke down before taking
action.
"We need only look at the problems that childhood obesity
rates will cause if they are not addressed to see how important it is
that we take 'cradle to grave' approach to public health."
No comments:
Post a Comment