Obesity has been linked to a number of health problems, including cardiovascular disease, diabetes, and certain types of cancer. Now, a study has found that obesity-related neurodegeneration can mimic Alzheimer’s disease, the most common form of dementia.
A new study led by scientists at The Neuro (Montreal Neurological Institute-Hospital) of McGill University finds a correlation between neurodegeneration in obese people and Alzheimer’s disease (AD) patients, suggesting that losing excess weight could slow cognitive decline in aging and lower risk for AD.
Previous research has shown that obesity is linked with Alzheimer’s disease (AD)-related changes, such as cerebrovascular damage and amyloid-β accumulation. However, to date no research has made a direct comparison between brain atrophy patterns in AD and obesity.
Our study adds to previous research pointing to obesity as a significant risk factor for Alzheimer’s disease by demonstrating that cortical thinning could be one of the potential risk mechanisms. Our findings emphasize the importance of losing weight in obese and overweight people in their forties to reduce the risk of neurodegeneration and dementia.
Filip Morys
The researchers compared patterns of grey matter atrophy in obesity and Alzheimer’s disease using a sample of over 1,300 people. They created maps of grey matter atrophy for each group by comparing AD patients to healthy controls and obese people to non-obese people.
Obesity and Alzheimer’s disease both affected grey matter cortical thinning in similar ways, according to the researchers. Thinning in the right temporo-parietal cortex and left prefrontal cortex, for example, was similar in both groups. Cortical thinning could indicate neurodegeneration. This suggests that obesity may cause the same type of neurodegeneration seen in Alzheimer’s patients.
Obesity is increasingly recognized as a multisystem disease affecting, among other things, the respiratory, gastrointestinal, and cardiovascular systems. This study, which will be published in the Journal of Alzheimer’s Disease, reveals a neurological impact as well, indicating that obesity may play a role in the development of Alzheimer’s and dementia.
“Our study adds to previous research pointing to obesity as a significant risk factor for Alzheimer’s disease by demonstrating that cortical thinning could be one of the potential risk mechanisms,” says Filip Morys, PhD researcher at The Neuro and the study’s first author. “Our findings emphasize the importance of losing weight in obese and overweight people in their forties to reduce the risk of neurodegeneration and dementia.”
The researchers found that the obese mice developed a type of neurodegeneration that resembled Alzheimer’s disease. Specifically, the mice had an accumulation of beta-amyloid plaques in their brains, which is a hallmark of Alzheimer’s disease. They also showed signs of cognitive impairment, such as memory loss and difficulty with learning and spatial navigation.
The researchers believe that the neurodegeneration observed in obese mice is caused by chronic inflammation, which is known to be associated with obesity. Inflammation in the brain can lead to damage of the neurons and synapses, which can ultimately lead to cognitive decline.
The study suggests that obesity may be a risk factor for developing Alzheimer’s disease and other forms of dementia. It also highlights the importance of maintaining a healthy weight and lifestyle to protect the brain from neurodegeneration.
