Association of midlife lipids with 20-year cognitive change: A cohort study

Introduction Existing studies predominantly consider the association of late-life lipid levels and subsequent cognitive change. However, midlife rather than late-life risk factors are often most relevant to cognitive health. Methods We quantified the association between measured serum lipids in midlife and subsequent 20-year change in performance on three cognitive tests in 13,997 participants of the Atherosclerosis Risk in Communities study. Results Elevated total cholesterol, low-density lipoprotein cholesterol, and triglycerides were associated with greater 20-year decline on a test of executive function, sustained attention, and processing speed. Higher total cholesterol and triglycerides were also associated with greater 20-year decline in memory scores and a measure summarizing performance on all three tests. High-density lipoprotein cholesterol was not associated with cognitive change. Results were materially unchanged in sensitivity analyses addressing informative missingness. Discussion Elevated total cholesterol, low-density lipoprotein cholesterol, and triglycerides in midlife were associated with greater 20-year cognitive decline.