| |
Heal the
heart, the mind will follow
(This article was first printed in the July
2005 issue of the Harvard Heart Letter.
For more information or to order, please go
to www.health.harvard.edu/heart.)
Strategies that protect you from a heart
attack or stroke can work against aging-related
memory loss.
Research is beginning to show how emotions,
isolation, and a host of other psychological
and social factors affect the heart. It works
the other way, too: The health of your heart
and blood vessels affects your mind and brain.
One of the hazards of living longer is the specter
of Alzheimer’s disease. This thief of memory
is relatively uncommon before age 60, but then
increases with each passing half-decade, eventually
afflicting just under half of those over age
85.
Numbers like these make it look as though losing
your memory is part of normal aging. It isn’t.
There is growing evidence that you might be able
to prevent it, or at least push it back, with
the same steps that help protect you from a heart
attack or stroke.
Types of memory loss
The term dementia is an umbrella for damage
to the brain that leads to memory loss, confusion,
and changes in personality or speech. This damage
can arise from a variety of causes, including
head injury, malnutrition, and disease. Among
older people, the most common causes are Alzheimer’s
disease and vascular dementia.
Alzheimer’s is a progressive degeneration
of the brain. Tangled strands of hairlike protein
accumulate inside brain cells. Outside, clumps
of a protein called beta-amyloid and debris from
broken-down brain cells cluster around the connections
between brain cells. The protein tangles and
clumps kill brain cells and make it difficult
for them to communicate with one another, leading
to loss of memory, confusion, and other changes.
Degeneration is also a hallmark of vascular
dementia. In this case it arises because lack
of oxygen kills cells in one or more sections
of the brain. This happens when small strokes
disrupt blood flow or narrowed arteries seriously
restrict it.
Some people have only Alzheimer’s disease,
and some have only vascular dementia. But about
half of those with memory loss and other symptoms
have both.
Common pathways
Research suggests that similar scenarios — involving
cholesterol-clogged arteries, inflammation, and
risk factors for heart disease and stroke — contribute
to both Alzheimer’s disease and vascular
dementia.
Restricted blood flow in the brain may contribute
to the cascade of events that leads to the tangles
and clumps of Alzheimer’s. Deposits of
beta-amyloid in blood vessels supplying the brain
make them more fragile and likely to burst, which
would cause a hemorrhagic stroke.
Some people develop the tangles and clumps associated
with Alzheimer’s without showing signs
of dementia. Autopsies show that memory loss
and changes in thinking skills and personality
are more likely to have occurred when tangles
and clumps are accompanied by signs of strokes
and restricted blood flow in the brain.
In other words, improving blood flow to the
brain and working to prevent strokes may maintain
memory well into old age.
Brain owner’s
guide
To keep your brain healthy, the Alzheimer’s
Association’s “Maintain Your
Brain” campaign offers these suggestions:
- Head first: Your
brain is one of the most vital body
organs, so take care of it.
- Take brain health to heart: Do
something every day to prevent heart
disease, high blood pressure, diabetes,
and stroke, all of which can increase
your risk of Alzheimer’s.
- Your numbers count: Keep
your body weight, blood pressure, cholesterol,
and blood sugar levels within recommended
ranges.
- Feed your brain: Eat
less saturated fat and more antioxidant-rich
fruits and vegetables.
- Work your body: Physical
activity keeps the blood flowing and
may encourage brain cell growth.
- Jog your mind: Keeping
your brain active and engaged increases
its vitality and builds reserves of
brain cells and connections. Read,
write, play games, learn new things,
do crossword puzzles.
- Connect with others: Leisure
activities that combine physical, mental,
and social elements may help the most.
- Protect your brain: Use
your seat belt when you drive, unclutter
your house to avoid falls, and wear
a helmet if you bicycle.
- Use your head: Avoid
unhealthy habits — don’t
smoke, drink too much alcohol, or use
street drugs.
|
Reverse the curse
A handful of studies link harmful habits or
health issues in midlife with memory loss or
declining thinking skills later on. In a 2005
report in the journal Neurology, researchers
with a large California HMO found that 40-year-olds
with four common cardiovascular risk factors — high
cholesterol, high blood pressure, diabetes, and
smoking — were more than twice as likely
to develop dementia as those with none of these
factors.
In a more positive light, there’s growing
evidence that healthful habits and changes are
good for the brain and the mind.
Exercise. Walk, run, swim,
cycle, garden, dance — better yet, do them
all — to keep both brain and body in shape.
Long-term regular physical activity has been
linked with better cognitive function and less
aging-related decline. A report from the Cardiovascular
Health Cognition Study suggests that the variety of
exercise, not just how much or how hard you exercise,
may help ward off dementia. Exercise also looks
like a way to prevent, and even treat, depression.
Blood pressure. Untreated high
blood pressure speeds aging-related decay in
thinking skills and memory. Pressure-lowering
drugs may help, although it isn’t clear
if one kind is better than another.
Dietary fat. Eating a lot of
saturated and trans fat may promote dementia,
while omega-3 fats may protect against the buildup
of sticky beta-amyloid clumps in the brain. Omega-3
fats may also be a good way to prevent depression.
Good sources of these healthful fats include
salmon, mackerel, and other cold-water fish,
as well as plant sources such as walnuts, canola
oil, and flaxseed.
Cholesterol-lowering statins. A
few studies suggest that people who take a statin
(Lipitor, Zocor, generic lovastatin, etc.) are
less likely to develop Alzheimer’s disease
than those who don’t take this type of
drug. If true, this would be an important “side
effect” of statins, which are popular medications
for fighting heart disease. At the same time,
reports of statin-associated memory loss have
appeared in medical journals.
Taking control
The intersection of cardiovascular health and
brain health is a relatively new field of research.
So far there are tantalizing hints — but
no guarantees — that doing what you can
to keep your heart and blood vessels in good
shape will do the same thing for your brain and
your mind.
It’s a gamble worth taking.
(This article was first printed in the July
2005 issue of the Harvard Heart Letter.
For more information or to order, please go
to www.health.harvard.edu/heart.)
|
|
HOME
MY
CART
12
monthly issues
