Seniors, Warning! Study Finds New Dementia Risk Factor
Age is one of the biggest risk factors for
dementia. The older we get, the higher our of dementia. But what is it
about advanced age that makes us more likely to develop this
debilitating disease?
Cardiovascular issues, chronic inflammation, and even hearing loss are
all correlated with dementia and are more common in seniors. Japanese
scientists have added a new and rather surprising risk factor -
sarcopenic obesity - to that list.
Dementia in Japan
The latest statistical estimates suggest
that 15% of older adults in Japan (aged 65 and older) suffer from
dementia, and the statistics are gradually increasing every year. To
compare, the Population Reference Bureau suggests that around 10% of
American seniors aged 70 and older suffer from this severe medical
issue. For Japan, a country that historically had one of the lowest
rates of dementia in the world, this was a wake-up call.
For understandable reasons, Japanese scientists were concerned. Why are
the cognitive abilities of more and more seniors withering away before
their eyes?
The Study
To investigate this alarming tendency, researchers at the Juntendo
University in Japan involved 1615 Japanese seniors in the 65-84 age
range from the Bunkyo Health Study, an ongoing cohort study of over 10
years. Their theory was that the increase in dementia is linked to two
other factors - sarcopenia and obesity - both of which have been shown
to increase the risk of cognitive issues in past studies.
As Dr. Yoshifumi Tamura, the lead researcher of the study, pointed out
to Scitech Daily, “If the association between sarcopenic obesity and
dementia is established, appropriate preventive measures can be taken to
reduce the occurrence of this condition and the risk of dementia in
elderly patients.”
The study was published in the March 2022 issue of the Clinical
Nutrition journal.
What is sarcopenic obesity?
Like dementia, obesity has gradually become
increasingly common in Japan. In the senior population, this condition
often appears hand in hand with sarcopenia - an age-related loss of
muscle mass and strength that typically begins after age 40. Together,
these two factors create a condition called sarcopenic obesity, where
weakness co-occurs with excessive weight.
Sarcopenic obesity is assessed by taking two measures into
consideration: handgrip strength to test sarcopenia and body mass index
(BMI) to measure obesity.
Having considered these measures, the participants were evaluated based
on their sarcopenia and obesity status and divided into four groups:
participants with obesity, sarcopenia, sarcopenic obesity, and control
subjects with neither obesity nor sarcopenia. The researchers then
compared each group’s cognitive and mental functions to see if there’s a
connection between sarcopenic obesity and dementia or moderate
cognitive impairment (MCI).
The Results
The four groups were divided as follows:
4.7% of the participants had sarcopenic obesity
14.6% had sarcopenia
21.2% had obesity
59.4% had neither obesity nor sarcopenia.
Despite making up the smallest percentage of the study population, the
sarcopenic obesity group had the greatest rate of dementia and MCI.
Sarcopenia was the second most significant risk factor, followed by
obesity. The study also pointed out sarcopenia is a significant risk
factor for dementia in females but not males. As expected, the controls
came last, meaning they had the lowest prevalence of MCI and dementia.
The Takeaway
To sum up, the results of the study are pretty clear-cut: sarcopenic
obesity can increase one’s risk of developing dementia and moderate
cognitive impairment. As Dr. Tamura stated, “This study clearly
demonstrates that sarcopenic obesity, defined by the combination of BMI
and hand grip strength is associated with MCI and dementia among Japan’s
elderly people.” We’ll be eagerly waiting if studies with a more
diverse population confirm these findings too.
Meanwhile, for the average person, the results of this study can be
translated into real-world, actionable advice. The research proves that
maintaining a healthy weight and exercising to keep muscle strength in
your senior years can do a lot more than make you look fit. It means
having a clear and healthy mind within a capable and fit body.