Researchers have discovered a significant link between changing cholesterol levels over time and the risk of dementia in older adults. This finding could pave the way for new early detection methods for cognitive decline.
Older adults whose cholesterol levels fluctuate over time are at higher risk of developing dementia than those with stable cholesterol, according to a study published in Neurology, the medical journal of the American Academy of Neurology.
The research does not establish causation but highlights a significant association that could transform how we detect and manage dementia risk.
“These results suggest that fluctuating cholesterol, measured annually, may be a new biomarker for identifying people at risk of dementia, providing more information than the actual cholesterol levels measured at a single time point,” lead study author Zhen Zhou, a research fellow in chronic diseases and aging at Monash University in Melbourne, Australia, said in a news release.
The study monitored 9,846 participants with an average age of 74, all free of dementia or memory problems at the outset. The participants’ cholesterol levels were tracked initially and then at three subsequent annual visits.
The participants also underwent annual memory tests, and they were observed for an average of 5.5 years after their last cholesterol measurement.
The participants using statins — common cholesterol-lowering medications — were included in the study unless they started or discontinued their medication during the cholesterol measurement period.
The participants were categorized into four groups based on the degree of change in their cholesterol levels from the study’s onset to the fourth measurement. The group with the most considerable variation in total cholesterol had an average change of 91 mg/dL, while the group with the least change had an average variation of 22 mg/dL.
Throughout the study, 509 participants developed dementia. Among those with the highest fluctuation in cholesterol, 147 out of 2,408 people (or 11.3 per 1,000 person-years) developed dementia.
In contrast, in the group with the least change, 98 out of 2,437 people (or 7.1 per 1,000 person-years) developed the condition.
When adjusted for factors like age, smoking status and high blood pressure, the research indicated that participants in the high-change group were 60% more likely to develop dementia compared to those in the low-change group.
Furthermore, the study discovered a connection between fluctuating LDL (“bad”) cholesterol levels and the risk of both dementia and cognitive impairment. However, this association was not observed with HDL (“good”) cholesterol or triglycerides.
“Older people’s cholesterol should be monitored for changes over time to help identify people who may be at risk of cognitive impairment or dementia and could benefit from interventions, which could include lifestyle changes or making sure they start or keep taking statin to prevent fluctuations in their cholesterol and potentially reduce the risk of dementia,” Zhou added.
One of the study’s limitations was the lack of information on any dosage changes in cholesterol medications or non-adherence to prescribed medication regimens, which could have influenced cholesterol level fluctuations.
This study opens up new avenues for dementia risk assessment and management. By focusing on the variability of cholesterol levels rather than a single measurement, health care providers might better identify individuals at risk for cognitive decline earlier, potentially implementing lifestyle or pharmaceutical interventions to stabilize cholesterol levels and reduce the risk of dementia.