Explaining the association between social and lifestyle factors and cognitive functions: a pathway analysis in the Memento cohort

Alzheimers Res Ther. 2022 May 18;14(1):68. doi: 10.1186/s13195-022-01013-8.

Abstract

Background: This work aimed to investigate the potential pathways involved in the association between social and lifestyle factors, biomarkers of Alzheimer's disease and related dementia (ADRD), and cognition.

Methods: The authors studied 2323 participants from the Memento study, a French nationwide clinical cohort. Social and lifestyle factors were education level, current household incomes, physical activity, leisure activities, and social network from which two continuous latent variables were computed: an early to midlife (EML) and a latelife (LL) indicator. Brain magnetic resonance imaging (MRI), lumbar puncture, and amyloid-positron emission tomography (PET) were used to define three latent variables: neurodegeneration, small vessel disease (SVD), and AD pathology. Cognitive function was defined as the underlying factor of a latent variable with four cognitive tests. Structural equation models were used to evaluate cross-sectional pathways between social and lifestyle factors and cognition.

Results: Participants' mean age was 70.9 years old, 62% were women, 28% were apolipoprotein-ε4 carriers, and 59% had a Clinical Dementia Rating (CDR) score of 0.5. Higher early to midlife social indicator was only directly associated with better cognitive function (direct β = 0.364 (0.322; 0.405), with no indirect pathway through ADRD biomarkers (total β = 0.392 (0.351; 0.429)). In addition to a direct effect on cognition (direct β = 0.076 (0.033; 0.118)), the association between latelife lifestyle indicator and cognition was also mostly mediated by an indirect effect through lower neurodegeneration (indirect β = 0.066 (0.042; 0.090) and direct β = - 0.116 (- 0.153; - 0.079)), but not through AD pathology nor SVD.

Conclusions: Early to midlife social factors are directly associated with higher cognitive functions. Latelife lifestyle factors may help preserve cognitive functions through lower neurodegeneration.

Keywords: Brain markers; Cognitive function; Lifestyle factors; Pathology; Pathways; Social factors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Alzheimer Disease* / pathology
  • Amyloid beta-Peptides / metabolism
  • Biomarkers
  • Cognition
  • Cognitive Dysfunction* / metabolism
  • Cross-Sectional Studies
  • Female
  • Humans
  • Life Style
  • Magnetic Resonance Imaging
  • Male
  • Positron-Emission Tomography
  • Vascular Diseases*

Substances

  • Amyloid beta-Peptides
  • Biomarkers