Age is a risk factor in the development of cognitive impairment and dementia, but age does not necessarily mean a chronological number alone. Epigenetic clocks measure biological age, which has strong potential for predicting cognitive impairment or dementia- an attractive capability backed by promising research for those seeking a personalized risk assessment in hopes of early intervention. In a study of 6,069 cognitively unimpaired women with a mean age of 70 years old tracked over ten years, the Women's Health Initiative Memory Study examined the rate of biological aging and its association with mild cognitive impairment and dementia using a few epigenetic clocks such as AgeAccelPheno, DunedinPace, and AgelAccelGrim2, ultimately discovering that AgeAccelGrim2 provided the strongest prediction of cognitive decline.
Epigenetic clocks are bioinformatics models used to estimate biological age, not chronological age, based on DNA methylation levels. DNA methylation influences gene expression, and as people age, their genomes undergo methylation changes that affect how genes express themselves. Researchers use a variety of epigenetic clock models and biomarkers to investigate aging ph...