Older adults whose cholesterol changes over time can develop dementia rather than people whose cholesterol is stable, regardless of the actual cholesterol levels, according to a study published in the online number of January 29, 2025, online Neurology®The Medical Journal of the American Academy of Neurology.
The study does not prove that changing cholesterol causes dementia; It only shows an association.
These results suggest that fluctuating cholesterol, measured annually, can be a new biomarker for identifying people who are at risk of dementia, offering more information than the actual cholesterol levels measured at a single time. “
Zhen Zhou, PhD, study author of Monash University in Melbourne, Australia
The study included 9,846 people with an average age of 74 who had no dementia or other memory problems. Cholesterol levels were measured at the start of the study and with three annual visits. Participants were followed on average 5.5 years after the third visit. They took annual tests of memory skills.
Participants who used cholesterol medicines, called Statins, were allowed in the study, unless they stopped or started taking the medicines during the measuring period for cholesterol.
The participants were divided into four equal groups based on the amount of change between their first and fourth cholesterol measurements. The difference between successive annual measurements was on average 91 mg/dl in the group with the largest amount of change in total cholesterol and 22 mg/dl in the group with the smallest amount of change.
During the study, 509 people developed dementia. A total of 147 of the 2,408 people in the group with the largest amount of change in total cholesterol developed dementia, a percentage of 11.3 per 1,000 person years. In the group with the lowest amount of change in total cholesterol, 98 of 2,437 people developed dementia, a percentage of 7.1 per 1,000 person years. Personal years represent both the number of people in the study and the amount of time that each person spends on the study.
After correction for other factors that can influence the risk of dementia, such as age, smoking status and high blood pressure, researchers discovered that they were 60% more likely to develop dementia in the high change group than in the low change group.
The study also found a connection between changing cholesterol levels and cognitive impairment or memory problems that did not meet the criteria for dementia.
Looking at the different types of cholesterol, researchers found a connection between fluctuating LDL cholesterol, or “bad” cholesterol and the risk of dementia and cognitive impairment. They did not find that association with HDL, or “good” cholesterol or triglycerides.
“Over time, the cholesterol of the elderly must be followed on changes to help people identify the risk of cognitive disorders or dementia and can benefit from interventions, including changes in lifestyle or ensuring that they start or keep taking To use statin to prevent fluctuations in their to prevent fluctuations in their cholesterol and possibly reduce the risk of dementia, “Zhou said.
A limitation of the research is that although people who started or stopped using cholesterol medicines were not included in the study to eliminate the fluctuations in cholesterol induced by medicines, researchers had no information about any changes in dosing or people who have their medicines have not used as prescribed that can influence cholesterol changes.
The study is supported by the National Heart Foundation of Australia.
Source:
Journal Reference:
Zhou, Z., et al .. (2025). Association from year to year lipid variability with the risk of cognitive decline and dementia in older adults with the community. Neurology. doi.org/10.1212/WNL.0000000000210247.