Preliminary research presented as an abstract at the American Heart Association's Scientific Sessions 2024 suggested a potential connection between variable cholesterol levels and increased dementia risk in older adults. These findings, which have not yet undergone peer review, emerged from analysis of the ASPirin in Reducing Events in the Elderly (ASPREE) trial data.
In the study of 9,846 adults averaging 74 years of age, researchers found participants with highly variable cholesterol levels showed a 60% increase in dementia risk compared to those with stable levels. During the six-year follow-up period, 509 participants developed dementia, while 1,760 demonstrated cognitive decline without dementia.
The research team recorded three consecutive annual measurements of total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides. Data showed participants in the highest quartile of total cholesterol variability experienced a 23% increase in cognitive decline risk. The study also found associations between LDL cholesterol fluctuations and decreased performance in memory tests and reaction speeds.
The study population included 55% women, with 87% of participants from Australia and 13% from the U.S. While 32% of participants used cholesterol-lowering medications, the researchers excluded individuals who modified their lipid-lowering regimens during the study period.
According to current health statistics cited in the abstract, 63.1 million U.S. adults had elevated LDL cholesterol between 2017 and 2020. CDC projections indicated dementia cases among adults 65 and older could increase from 7 million in 2014 to approximately 14 million by 2060.
The research team diagnosed dementia through multiple methods, including expert panel reviews of cognitive tests, self-reported problems, medical records, and prescription of dementia medications. Findings showed no significant associations between HDL cholesterol or triglyceride fluctuations and cognitive decline or dementia risk.
The abstract noted several limitations. The study population consisted predominantly of white adults (96%), potentially limiting result generalizability. Multiple factors could influence cholesterol readings, and the observational study design prevented determination of cause-and-effect relationships. The findings await peer review and publication in a scientific journal.
Zhen Zhou, PhD, a postdoctoral research fellow at Monash University's School of Public Health and Preventive Medicine in Melbourne, Australia, served as lead author of the abstract.
