Genetic Variation Underlying Traumatic Brain Injury (TBI) and Late Onset Alzheimers Disease (LOAD)
Abstract
Age-related changes in memory function are not uniform even in the absence of dementia and contributing factors are unclear. Characterization of non-disease associated cognitive changes is crucial to gain a more complete understanding of brain aging. Episodic memory was investigated in 13,979 ethnically diverse elderly (ages 72 to 85 years) with two to 15 years of follow-up, and with known dementia status, age, education and APOE genotypes at baseline. Adjusted trajectories of episodic memory performance over time were estimated using Latent Class Mixed Models. We also calculated the age-specific annual incidence rates of dementia in the non-demented elderly (n=10,659). Two major episodic memory trajectories were estimated within each of the study groups: 1) Stables - consisting of individuals exhibiting a constant or improved memory function over time and 2) Decliners - consisting of individuals with a decline in memory performance over time. Compared with the individuals in the Stable trajectory, Decliners were more likely women, older, less educated, from non-White ancestry population and APOE-epsilon 4 carriers. The highest annual incident rates of dementia were observed in the oldest age group (85 years old), among those of Caribbean-Hispanics ancestry and among Decliners who exhibited rates of incident dementia five times higher than those with Stable trajectories (rates= 15 per 100 person per year versus 3 per 100 person-per year). Episodic memory can be preserved over time among elderly regardless of ethnic group. Age, gender, education and APOE genotype influence the maintenance of episodic memory over time. Declining memory over time is one of the strongest predictors of incident dementia.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2018
- Accession Number
- AD1094319
Entities
People
- Badri N. Vardarajan
Organizations
- Columbia University