July 6, 2023 – Older people who have large changes in the amount of fat in their blood may have a higher risk of getting dementia, a new study shows.
Levels of cholesterol and triglycerides have long been linked to heart problems. Now, this latest analysis shows that people ages 60 and older who had the greatest variations in total cholesterol and triglyceride levels over the course of 5 years had up to a 23% increased risk of developing dementia.
Researchers also found that the increased risk due to fluctuations in total cholesterol or in triglycerides was present even for people who took medication to manage their cholesterol. The study also looked at LDL and HDL cholesterol variations, but fluctuations in those standalone measures didn’t have a link to dementia.
The findings were published Wednesday in the journal Neurology. Researchers analyzed health records for 11,571 people, who all lived in the Minnesota county where the Mayo Clinic is located. The average age of people in the study was 71 years old, and 96% of them were White. None of them had a previous dementia diagnosis at the start of the study. During the following 10 years, 21% of the people had Alzheimer’s or another form of dementia.
Dementia refers to problems with memory, thinking, and decision-making that are so severe, they interfere with a person’s everyday life. Alzheimer’s disease is the most common type of dementia. More than 5 million people ages 65 and older in the U.S. have dementia, and the CDC projects that number will grow to 14 million by 2060.
The researchers noted that previous research has shown that total cholesterol variation is a predictor of heart problems and of early death. Although their findings were not able to point to a cause, the researchers wrote that one theory of how lipid variation contributes to dementia is that narrowed arteries can lead to decreased blood flow to the brain.
“Routine screenings for cholesterol and triglyceride levels are commonly done as part of standard medical care,” researcher Suzette J. Bielinski, PhD, of the Mayo Clinic, said in a statement. “Fluctuations in these results 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.”