• Posted July 6, 2023

Keeping Cholesterol Levels Stable May Help Shield You From Dementia

Could swings in your blood fat levels increase your chances of being diagnosed with Alzheimer's disease?

Yes, suggests a new study that found fluctuating cholesterol levels among older adults may increase the risk for Alzheimer's disease and other dementias.

Those who had the most fluctuations in cholesterol had a 19% higher risk of developing Alzheimer's or dementia, and those with the most fluctuations in triglyceride levels had a 23% increased risk, the researchers found.

Still, Dr. Marc Lawrence Gordon, chief of neurology at Northwell Health's Zucker Hillside Hospital in Great Neck, N.Y., stressed this study can't prove these variations actually cause Alzheimer's disease or dementia.

"You don't know whether the fluctuation is what's driving the incidence of dementia or an increased incidence of dementia is somehow causing fluctuations," said Gordon, who had no part in the study. "I could not advise any of my patients to do anything in particular on the basis of these data."

However, lead researcher Suzette Bielinski, from the Mayo Clinic in Rochester, Minn., believes the findings could be helpful.

"Fluctuations in these results [cholesterol and triglycerides tests] over time could potentially help us identify who is at greater risk for dementia, help us understand mechanisms for the development of dementia, and ultimately determine whether leveling out these fluctuations could play a role in reducing dementia risk," she said in a statement.

For the study, Bielinski and her colleagues collected data on more than 11,500 men and women aged 60 and older who did not have Alzheimer's or other dementia.

The investigators found that over an average of 13 years of follow-up, those who had the most variation in their cholesterol levels saw a greater risk for mental decline.

Of the more than 2,400 people who developed Alzheimer's or dementia, 515 with the most variations in cholesterol levels developed dementia, compared with 483 of those who had the least variation.

These results were after the researchers adjusted for factors such as sex, race, education and cholesterol-lowering medications.

"It remains unclear why and how fluctuating levels of cholesterol and triglycerides are related to the risk of Alzheimer's disease," Bielinski said.

The report was published online July 5 in the journal Neurology.

One expert said that heart health and brain health are intertwined, and that keeping your cholesterol and triglycerides in check might play a part in preventing dementia.

"Heart health and brain health are closely related," said Christopher Weber, director of global science initiatives at the Alzheimer's Association.

Cholesterol fluctuations can affect the brain's vascular health and contribute to an increased risk of developing cognitive (mental) decline and dementia, including Alzheimer's disease, he said.

Also, the dysfunction of blood vessels in the brain could contribute to the connection between cholesterol fluctuations and Alzheimer's, Weber noted.

"This could affect cerebral blood flow and increase the risk of cognitive impairment and Alzheimer's in later life," he said.

Weber added that maintaining a low and stable level of cholesterol and triglycerides may be beneficial for reducing the risk of developing Alzheimer's.

"You should always consult your doctor or health care provider if you are concerned about your cardiovascular health, cholesterol levels or cognitive decline. Know your heart health numbers, get treatment when you need it, and live an overall heart- and brain-healthy lifestyle," Weber advised.

"Research is still evolving, but evidence is strong that people can reduce their risk of cognitive decline by making key lifestyle changes, including participating in regular physical activity, staying socially engaged and maintaining good heart health," Weber said.

More information

For more on Alzheimer's disease, head to the Alzheimer's Association.

SOURCES: Christopher Weber, PhD, director, global science initiatives, Alzheimer's Association; Marc Lawrence Gordon, MD, chief, neurology, Northwell Health Zucker Hillside Hospital, Great Neck, N.Y.; Neurology, July 5, 2023, online