More than 55 million people worldwide have dementia, a number expected to nearly triple by 2050. Deaths from strokes may double by the same year, and 10% to 20% of adults experience depression later in life.
While the numbers are striking, there’s a growing body of
evidence showing that many of these cases may not be genetically fated,
but rather could be delayed or prevented altogether by addressing health
factors generally within our control.
At least 17 factors contribute to dementia, stroke and late-life depression, according to an extensive review published Wednesday in the Journal of Neurology, Neurosurgery, and Psychiatry.
Addressing the 17 factors can reduce people’s risk for all
three conditions. Those factors are, in no order of importance:
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Blood pressure(Was fine until after the stroke)
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Body mass index(Was fine until after the stroke)
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Kidney disease(None)
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Blood sugar(Great)
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Total cholesterol(Decent)
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Alcohol use(Moderate)
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Diet
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Hearing loss or impairment(None)
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Pain(None)
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Physical activity(Off the charts)
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Purpose in life(Having fun)
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Sleep(Decent)
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Smoking(None)
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Social engagement(Mimimal, still was married)
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Stress(Minimal)
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Cognitive activity during leisure time(Leisure time was athletic)
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Depressive symptoms(None)
“This study just really shows how powerful lifestyle and
behavioral changes are for age-related brain diseases,” said senior
study author Dr. Sanjula Singh, an instructor in neurology at Harvard
Medical School and principal investigator at the Brain Care Labs at
Massachusetts General Hospital.
“Ultimately, we hope that people feel like there’s a hopeful
message in here — that there are actually so many things that you can
work on, and then not only your risk of stroke is lower, but also of
dementia and/or of late-life depression,” Singh noted.
In the past, studies, tools or risk-prediction models have
usually focused on these conditions individually. “From a human
perspective, that doesn’t make a lot of sense,” Singh said.
Ideally, people wouldn’t want to develop any of these
conditions, she added, so the research team wanted to find shared risk
factors so people can essentially achieve multiple goals using the same
tools.
The authors reviewed 59 meta-analyses — syntheses of data
from multiple similar studies — that were published between 2000 and
2023 and had investigated the effects of modifiable risk factors on
stroke, dementia and/or late-life depression among adults who weren’t
previously diagnosed with these conditions.
All 17 factors were shared by at least two of the
conditions, but there were no meta-analyses on relationships between
late-life depression and 11 of the health measures: alcohol intake, BMI,
blood sugar, cognitive activity, diet, hearing loss, kidney function,
pain, physical activity, social engagement and stress, according to the
study.
Of all the measures, blood pressure had the biggest impact. A normal blood pressure level
is below 120 over 80 millimeters of mercury, or mm Hg. People with a
level of 140/90 mm Hg or greater were more than twice as likely to have a
stroke, 20% more likely to develop dementia and 16% more likely to
experience depression.
Other top influential factors were smoking, sleep, physical activity and blood sugar.
“Grouping these all together is important, because I think
different people derive different levels of motivation to make a
behavior change” based on their personal concerns, such as a family
history of dementia, stroke or depression, said Dr. Richard Isaacson,
preventive neurologist and director of research at the Institute for
Neurodegenerative Diseases in Florida. Isaacson wasn’t involved in the
study.
“Data studies like this can help empower people to make
meaningful changes in their day-to-day lives,” Isaacson added.
If 17 items seem overwhelming, look at it as a menu from
which you can choose a few items — and work your way through the list
over time, Singh said. But also know these factors overlap, she said —
if you’re improving your diet and exercise, for example, you’re probably
improving several things on that list, including blood pressure, blood
sugar, sleep and cholesterol.
Not sure what to choose? Here’s how you can address what
experts said are some of the most important determinants of dementia,
stroke and depression.
Lowering high blood pressure: High blood
pressure means less blood flow to the brain,(Really? What about this? Data from animal models of hypertension indicate that high blood pressure may develop as a vital mechanism to maintain adequate blood flow to the brain). which has a direct
relationship with stroke and dementia, but is also associated with
depression by way of reducing neurotransmitters in the brain, Isaacson
said.
To address high blood pressure, you can have your level
checked by a machine at a drugstore, a doctor or a home device, experts
said. Lowering salt intake and getting enough potassium
are important for reducing blood pressure, as well as exercising,
losing excess weight, managing stress and seeing a sleep specialist if
you have sleep apnea. A doctor can determine whether you also need medication.
Stop smoking: If you smoke, there are five actions
you can take right now to quit, which concern identifying your
triggers, learning from relapses, using helplines and apps, and speaking
with doctors who can help you devise a treatment plan.
Improve your fitness: For physical activity, know that any amount is better than none — and the World Health Organization has guidelines for the type, frequency and duration of exercise you need depending on your age.
