New research found that experiencing rapid weight loss could be an indicator of higher dementia risk for older adults

Quick, Unexpected Weight Loss in Older Adults May Mean Higher Risk of Dementia Later On Here's what experts think

New research found that experiencing rapid weight loss could be an indicator of higher dementia risk for older adults

• New research found that, for older people, rapid weight loss was linked to a higher risk of developing dementia later in life.
• While the study found a connection between the two, it’s unclear if weight loss increases dementia risk or if the developing dementia causes weight loss.
• However, losing weight is a natural part of aging, and experts said it doesn’t always mean someone will develop cognitive issues.

Weight loss could be an indicator that someone is at higher risk for developing dementia—even before there are more obvious signs, a new study found.

A study published this month in JAMA Network Open assessed how cardiometabolic risk factors such as obesity, high cholesterol, diabetes, and high blood pressure might serve as early markers for dementia down the line.

Researchers followed healthy seniors who did and didn’t develop dementia over the course of 11 years. Interestingly, they found that participants who were diagnosed with dementia had a faster decline in body mass index (BMI) in the years before their diagnosis as compared to those who didn’t develop the condition.

People with dementia also tended to have higher levels of high-density lipoprotein (HDL, or “good” cholesterol) about five years prior to their diagnosis.

“Dementia develops over many years before symptoms become noticeable,” study co-author Zimu Wu, PhD, chronic disease and aging research fellow at Monash University in Australia, told Health. “This study suggests that weight loss and metabolic changes may occur during the early phase.”

About 6.9 million U.S. adults have Alzheimer’s disease, the most common form of dementia, and that number may double by 2060. Finding more ways to identify people at risk of these cognition issues could be one way of addressing this growing public health issue and might make it easier for people to get dementia treatment early, when it’s most effective.

A Deeper Look at the Research

Cardiometabolic risk factors such as uncontrolled diabetes and high blood pressure are well-established risk factors for dementia.

And earlier research has found links between declining BMI and other cardiometabolic changes and dementia. However, prior studies had limitations, including small sample sizes and reliance on hospital records, the study authors noted.

To fill these gaps, Wu and the other researchers used data obtained between 2010 and 2017 from the Aspirin in Reducing Events in the Elderly (ASPREE) trial and a follow-up observational study, ASPREE Extension, from 2019 onward. Data was collected from participants in Australia and the U.S. aged 65 years and older without major cognitive deficits, physical disability, or cardiovascular disease.

The study included nearly 5,400 participants, and between 2010 and 2022, researchers tracked various measures of their cardiometabolic health. This included BMI, waist circumference, and blood pressure, as well as glucose, triglyceride, low-density lipoprotein (LDL), HDL, and total cholesterol levels.

In the end, 1,078 people developed dementia, and 4,312 did not. The research team then compared the trajectories of these various health metrics among the two groups.

All of the participants had a steady decline in BMI as they aged; however, those with dementia had a lower baseline BMI and had a steeper decline beginning at least 11 years before their dementia diagnosis.

Those with dementia also had a significantly lower waist circumference 10 years prior to diagnosis as compared to people who didn’t later develop the condition.

Changes in blood pressure, triglyceride levels, glucose levels, and total and LDL cholesterol levels were similar, regardless of whether people developed dementia. However, people with dementia had greater increases HDL cholesterol levels, specifically between 11 and four years prior to their diagnosis.

How Are Weight Loss and Dementia Linked?

While study results might make it seem like weight loss increases dementia risk, the opposite is more likely true, explained Willa Brenowitz, PhD, MPH, epidemiologist and investigator with the Kaiser Permanente Center for Health Research. This is something researchers refer to as “reverse causation,” she told Health.

“This is often brought up in studies evaluating BMI or weight loss as a risk factor for dementia,” Brenowitz said. “Weight loss is associated with dementia because dementia is causing the weight loss.”

There are several reasons why this might be the case, Wu added.

“Weight loss may be an early sign of dementia-related brain changes that affect appetite, metabolism, and daily function,” said Wu. “Lifestyle changes associated with these brain changes—like forgetting to eat, difficulty preparing food, reduced physical activity and social engagement—may also contribute.”

As for the increases in HDL cholesterol levels among people with dementia, it could be that the body is responding to very early changes in brain function, Wu said. However, the reasons aren’t well understood and more research is needed.

Importantly, with how this study was conducted, it’s not clear whether weight loss and increasing HDL cholesterol levels are actually early symptoms of dementia, or if they’re risk factors for the condition, explained Brenowitz. This distinction is key for improving dementia diagnosis, she said.

Another limitation is the lack of diversity among participants.

“The study was more than 95% white, which raises the question of how generalizable findings would be to other racial and ethnic groups,” including Black and Hispanic Americans, who are at a higher risk of cardiometabolic disease and dementia compared to white populations, said Brenowitz.

Further in-depth research with longer study periods and more diverse participants is needed to better understand how cardiometabolic changes and dementia actually affect one another, she added.

Is Losing Weight as an Older Adult Always a Cause For Concern?

The study did find that people who went on to be diagnosed with dementia had a steeper decline in BMI and waist circumference as compared to those with normal cognition. But importantly, all participants lost weight—in many cases, it’s a common part of aging, and doesn’t always mean that someone will develop cognitive issues.

“While this pattern was observed, how to differentiate these [weight] changes from normal aging in practical settings is beyond the scope of this study,” said Wu. “[This] highlights the need for further research.”

It’s also not clear how strong of a warning sign or risk factor significant weight loss could be for dementia, added Brenowitz.

Unintentional weight loss would have to be considered alongside other measures such as cognitive tests, neuroimaging, and biomarkers to see whether it was connected to dementia, normal aging, or something else, she advised.

However, if someone is experiencing other signs of dementia—including changes in attention span, judgement, problem solving, or the ability to communicate—that would certainly warrant further investigation.

“Cognitive health is likely best checked if there are other potential reasons for concerns such as someone noticing they or a family member is having more memory issues than before, or other cognitive changes,” Brenowitz said.

Julia is a news reporter and editor for Health, where she covers breaking and trending news on health and wellness topics. Her work has been featured in The Heights, an independent student newspaper at Boston College, and Minnesota Monthly.

This story originally appeared on: Health News - Author:Cathy Nelson