Reprinted from: http://www.cbsnews.com/news/one-third-of-dementia-cases-could-be-prevented-alzheimers-report/?WT.mc_id=enews2017_07_31&utm_source=enews-aff-28&utm_medium=email&utm_campaign=enews-2017-07-31
By ASHLEY WELCH CBS NEWS July 20, 2017, 5:00 AM
One-third of cases of dementia worldwide could potentially
be prevented through better management of lifestyle factors such as smoking,
hypertension, depression, and hearing loss over the course of a lifetime,
according to a new report.
Across the globe, about 47 million people were living with
Alzheimer's and other forms of dementia in 2015. That number is projected to
triple by the year 2050 as the population ages. Health care costs associated
with dementia are enormous, with an estimated $818 billion price tag in 2015.
The new study, published in The Lancet and conducted by the
first Lancet Commission on Dementia Prevention and Care, brought together 24
international experts to review existing dementia research and provide
recommendations for treating and preventing the devastating condition.
"Dementia is the greatest global challenge for health
and social care in the 21st century," lead study author Professor Gill
Livingston, of University College London, told CBS News. "The purpose of
the commission was therefore to address it by consolidating the huge strides
and emerging knowledge as to what we should do to prevent dementia and
intervene and care for people with dementia."
There is currently no drug treatment to prevent or cure
dementia. But the report highlights the impact of non-drug interventions and
identifies nine modifiable risk factors through various stages of life —
beginning in childhood — that affect the likelihood of developing dementia.
To reduce the risk, factors that make a difference include getting
an education (staying in school until over the age of 15); reducing high blood
pressure, obesity and diabetes; avoiding or treating hearing loss in mid-life;
not smoking; getting physical exercise; and reducing depression and social
isolation later in life. About 35 percent of dementia cases are attributable to
these factors, the analysis found. Removing them could then theoretically
prevent 1 in 3 cases.
In contrast, finding a way to target the major genetic risk
factor, a gene called the apolipoprotein E (ApoE) ε4 allele, would prevent less
than 1 in 10 cases – or about 7 percent.
"There's been a great deal of focus on developing
medicines to prevent dementia, including Alzheimer's disease," commission
member Lon Schneider, M.D., a professor of psychiatry and the behavioral
sciences at the Keck School of Medicine of USC, said in a statement. "But
we can't lose sight of the real major advances we've already made in treating
dementia, including preventive approaches." Schneider presented the
findings at the Alzheimer's Association International Conference (AAIC) 2017.
Of the nine risk factors, the researchers identified the
three most common ones that could be targeted for dementia prevention.
The first is increasing education in early life, which the
report estimated could reduce the total number of dementia cases by 8 percent
if all people worldwide continued their education until over the age of 15.
The researchers note that not completing secondary education
could raise dementia risk by reducing what's referred to as "cognitive
reserve." It's believed that education and other mentally stimulating
tasks help the brain strengthen its networks so it can continue to function at
a higher level even if it starts to decline later in life.
For the first time, the researchers also identified hearing
loss as a major modifiable risk factor for dementia. They estimated that
reducing hearing loss in mid-life could also reduce the number of dementia
cases by 9 percent if all people were treated.
Livingston notes that research surrounding hearing loss and
dementia is still in early stages and the link likely has something to do with
the social isolation that can come with losing the ability to hear.
"They may work in similar ways as they reduce the
chance of interactions and conversations, which are like exercise for the brain
and enrich it and predispose to depression," she said.
It's not clear from medical research yet whether using
hearing aids can counteract this risk.
Additionally, the researchers found the number of dementia
cases worldwide could be reduced by 5 percent if all people stopped smoking.
It's particularly important to stop smoking later in life, they say, to reduce
neurotoxins and improve heart health, which in turn improves brain health.
Other interventions likely to reduce dementia rates include
increased physical activity and treating high blood pressure and diabetes.
The study authors say the report can offer guidance on ways to
reduce the risk of dementia throughout life and improve the care for those
living with the disease.
"This includes providing safe and effective social and
health care interventions in order to integrate people with dementia within
their communities," Schneider said. "Hopefully this will also ensure
that people with dementia, their families and caregivers, encounter a society
that accepts and supports them."
It's important to note that lifestyle interventions will not
delay or prevent all dementia cases. But the researchers say they are hopeful
that the report will help shift more focus to concrete steps that can be taken
to help avoid the disease.
"We hope that this report will feed into individual
nations' dementia policies and public health strategies, be used by individual
clinicians to inform and improve their practice, and through media publicity
inform the general public of what they can do to help avoid dementia, which is
the most feared illness in old age."
© 2017 CBS Interactive Inc. All Rights Reserved.
