Researchers conducting scientific research on indigenous peoples in the Bolivian Amazon have found that members of an indigenous tribe have very low rates of dementia.
The new study follows previous findings that the same people have virtually no cases of age-related heart disease, according to New Atlas, citing Alzheimer’s & Dementia.
Very good elderly health
The Tsimane, pronounced in the indigenous language Chimahnae, are a unique group of regarding 17,000 people who live in remote parts of Bolivia and have undergone a lot of research over the past few decades due to their unusually good health at an older age.
young arteries
In 2017, researchers working on a research project titled “The History and Health of the Tsimani Tribe” discovered surprisingly low levels of vascular aging in adults in the Tsimane tribe. Eighty-five percent of Tsimane adults had no risk of heart disease, and a study in the Lancet estimated that Tsimane adults, with an average age of 80, had blood vessels similar to those of American adults, 25 years younger.
Brain health and dementia
The new study focused on the brain health and dementia of the Tsimane. The study included 435 adults, over the age of 60. Using a local team of carefully trained doctors and translators, participants in Tsimane completed a number of neurological assessments, including CT brain scans and cognitive tests.
Only 1% cases of dementia
Only five cases of dementia were detected in the Tsimane cohort, equivalent to regarding 1% of the population, which contrasts with regarding 11% of the American population, of the same age, with dementia.
For comparison, the researchers also examined 169 people from the Musiten, a community genetically and linguistically similar to the Tsimane. The Mussetines showed similar low levels of dementia despite living close to modern Bolivian society.
subsistence life
“It appears that something related to the pre-industrial subsistence lifestyle was what prevented the elderly Tsimane and Mussetin from developing dementia,” said study lead author Margaret Gatz.
Interestingly, the study found that both Tsimane and Mussetin showed MCI rates of 8% and 10%, respectively, which were similar to those seen in Western high-income countries. But mild cognitive impairments were less likely to develop dementia in old age and were also characterized by unusual brain disease.
unusual phenotype
The authors wrote in the study: “…we were struck by an unusual phenotype of dementia and mild cognitive impairment, associated with prominent medial arterial calcifications affecting the internal carotid, vertebral and intracranial lenticular arteries. Notably, the severity of acute intracranial vascular calcification was related to volumes of smaller brain and greater risk of cognitive impairment.”
The researchers added that these types of calcifications appear to be associated with cognitive problems similar to those seen with Parkinson’s disease. The researchers noted that it is not clear at this stage whether the unique brain diseases are caused by genetic factors or other infectious and inflammatory disorders that are unique to these communities.
slower contraction of the brain
A study published last year found findings more specifically on CT scans, revealing that the Tsimane showed significantly lower rates of age-related brain atrophy than was observed in Western populations. Human brain size decreases with age, but the study revealed that Tsimane brains appear to shrink 70 percent more slowly than the brains of Western societies.
strange phenomenon
The strangest part of the study’s findings, which carried out computerized tomography scans, was the finding that despite reduced brain atrophy, Tsimane brains still displayed unusually high levels of neuroinflammation. The researchers were unable to explain this strange discrepancy and hypothesized that it was possible that high levels of inflammation were linked to an ongoing confrontation with infectious diseases. It is suspected that lifestyle factors in a vast natural environment may maintain brain health in the face of significant chronic inflammation.
Negatives of modern life
The researchers suggest that generally healthy lifestyle factors may be the most likely explanation for the lower rates of dementia and cardiovascular disease in the Tsimane. Although aging is a primary risk factor for conditions such as cognitive decline, study co-author Benjamin Trumbull said studying older Aboriginal people might reveal just how harmful our modern lifestyles are to health in advanced years.
“By working with populations such as the Tsimane and Museten, we can gain a better understanding of global human diversity and what human health was like in different environments before the industrial age,” Trumbull said, explaining that “what we do know is that sedentary, urban industrial life is completely new when Compare it to the way the ancestors lived for more than 99% of humanity’s existence.”
