A new study claims that unexplained variations in the cholesterol of older adults may be a sign of dementia risk.
The study, which will be presented at the American Heart Association Scientific Sessions in Chicago November 16-18, found that older adults who display significant fluctuations in cholesterol levels from year to year—without any explainable reason, like a change in medication—are at a higher risk of developing dementia or experiencing cognitive decline.
Researchers examined nearly 10,000 adults in the United States and Australia over six years to determine the findings.
“Older people with fluctuating cholesterol levels unrelated to whether they were taking lipid-lowering medications – particularly those experiencing big year-to-year variations — may warrant closer monitoring and proactive preventive interventions,” said Zhen Zhou, Ph.D., the study’s lead author and a postdoctoral research fellow in the School of Public Health and Preventive Medicine at Monash University in Melbourne, Australia.
Earlier this month, The Dallas Express reported on another dementia study that linked sleepiness to the condition.
In that study, published in Medical Neurology on November 6, researchers concluded that more than a third of older individuals suffering from excessive daytime sleepiness combined with low motivation ended up developing motoric cognitive risk syndrome, a precursor to full-blown dementia.
To conduct the latest study, researchers leveraged data from a randomized clinical trial called ASPirin in Reducing Events in the Elderly (ASPREE). The roughly 10,000 trial participants were relatively healthy, with a third taking cholesterol-lowering medication. Critically, none started, stopped, or altered their lipid-lowering medication dose in the follow-up period.
During the trial, participants recorded their cholesterol levels annually. The authors of the recent study used the first three annual measurements as a baseline to determine each individual’s year-to-year lipid variability.
Over nearly six years of follow-ups, 509 people developed dementia. An additional 1,760 experienced cognitive decline without dementia.
The researchers found that individuals with the highest fluctuations (top 25%) in cholesterol faced a 60% increase in dementia and a 23% increase in cognitive decline. The study also found that low-density lipoprotein (LDL) cholesterol, commonly called ‘bad’ cholesterol, and cholesterol variability were associated with significantly deteriorating cognitive health test scores when assessing memory and reaction speed.
The study is not without caveats.
Cholesterol readings can change for numerous reasons. Moreover, factors that were not assessed may also be responsible for the variability and formation of dementia.
“If future research confirms a cause-and-effect relationship, reducing cholesterol variability could potentially be a promising therapeutic target for dementia,” Zhou said.
