Social support moderates the influence of Alzheimer’s disease–related neurodegeneration on cognitive decline

Abstract

AbstractBackgroundSocial support (SS) have been associated with decreased rate of cognitive decline in Alzheimer’s disease (AD). However, it is still unclear whether SS can moderate the influence of AD‐related neurodegeneration on cognitive decline. We aimed to test the hypothetical moderation effect of SS on the relationship between AD‐related brain atrophy and cognitive decline.MethodTotal 200 participants from the Korean Brain Aging Study for Early Diagnosis & Prediction of Alzheimer’s disease (KBASE), an ongoing prospective cohort study, were included for this analysis. Of the 200 participants, 130 were MCI and 70 were early AD. All participants underwent comprehensive clinical and neuropsychological assessment, multi‐modal neuroimaging including magnetic resonance imaging, and apolipoprotein E genotyping. AD‐signature cortical thickness (AD‐CT) was defined as a mean cortical thickness of several brain regions known to be sensitive to AD‐specific neurodegeneration. The Medical Outcome Study – Social Support Survey (MOS‐SSS), a 19‐iem brief, multi‐dimensional, self‐report social support survey, were administered to all participants to assess overall SS indices. Global cognitive performance was measured by the total score of the Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological test battery (CERAD‐TS).ResultThere was a significant interaction between AD‐CT and SS on CERAD‐TS. Subgroup analyses demonstrated that the association between AD‐CT and CERAD‐TS was weaker in high SS group than in low SS group.ConclusionOur results suggest that SS may delay the progression of cognitive decline by moderating the influence of AD‐related neurodegeneration.