Higher midlife CAIDE score is associated with increased brain atrophy in a cohort of cognitively healthy middle-aged individuals

Xulin Liu, Maria-Eleni Dounavi, Karen Ritchie, Katie Wells, Craig W. Ritchie, Li Su, Graciela Muniz-Terrera & John T. O’Brien

Journal of Neurology. 2021

DOI: https://doi.org/10.1007/s00415-020-10383-8

Summary
Cardiovascular factors have a strong association with Alzheimer’s disease (AD) and brain atrophy. However, until recently, there has been limited longitudinal research in cognitive healthy middle-aged adults investigating these links. A recent PREVENT Dementia study used data from 167 participants in the PREVENT London cohort, to investigate associations between the CAIDE (Cardiovascular Risk Factors, Aging, and Dementia) score and structural MRI scans at both baseline and 2-year follow up. Participants in the high-risk group (i.e., those with a CAIDE score above 6) were on average, found to have a greater rate of brain atrophy. However, to identify the specific regions and structures driving this atrophy pattern, additional analysis was conducted using voxel based morphometry (VBM).

By using VBM to build on existing findings, the current study found significant associations between risk status determined based on the CAIDE score and grey matter atrophy in several regions, including the temporal, occipital, and fusiform cortex and lingual gyrus at baseline. Longitudinally, the supramarginal gyrus, angular gyrus, precuneus, lateral occipital cortex, superior parietal lobule and cingulate gyrus demonstrated accelerated atrophy over time. Many of these regions belong to the “AD signature cortical region” and are involved in processes such as consciousness and memory. This study highlights the potential for early interventions that focus on modifiable midlife vascular risk factors.

Key terms and abbreviations:

  • Atrophy= the progressive reduction in tissue
  • CAIDE score =Cardiovascular Risk Factors, Aging, and Incidence of Dementia score; A validated midlife dementia risk score, based on several factors, including age, gender, education, blood pressure, cholesterol, body mass index, physical activity and APOEe4 allele carriership.
  • VBM= Voxel based morphometry: An MRI technique that enables investigation of focal differences in anatomy throughout the brain
  • APOEe4 allele= One of the strongest genetic risk factors for Alzheimer’s disease​