Older people who have fluctuating levels of cholesterol and triglycerides may have a higher risk of Alzheimer’s disease and related dementias compared to people who have steady levels, according to new research

Researchers used healthcare data to identify 11,571 people (average age, 71; 98%, white) who did not have a prior diagnosis of Alzheimer’s disease or dementia. They looked at participants’ measures of total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) on at least three different days in the five years before the start of the study.

Then the team divided participants into five equal groups based on how much the measurements fluctuated. The lowest group had the least variation over time and the highest group had the most variation.

Participants were followed for an average of 13 years. During that time, 2,473 people developed Alzheimer’s disease or another form of dementia.

After adjusting for variables that could affect risk of dementia including sex, race, education and lipid-lowering treatments, the team found for total cholesterol, participants in the highest group had a 19% increased risk of dementia compared to those in the lowest group. Of the 2,311 people in the highest group, 515 developed dementia compared to 483 of the 2,311 people in the lowest group. For triglycerides, those in highest group had a 23% increased risk.

No link was found between variations in LDL and HDL and an increased risk of dementia.

"Prevention strategies for Alzheimer's and related dementias are urgently needed," said study author Suzette J. Bielinski, PhD, of the Mayo Clinic in Rochester, Minnesota. "Routine screenings for cholesterol and triglyceride levels are commonly done as part of standard medical care. 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."

To read the study abstract, published in Neurology, click here