Midlife CAIDE Dementia Risk Score and Dementia-Related Brain Changes up to 30 Years Later on Magnetic Resonance Imaging

Abstract

CAIDE Dementia Risk Score is a validated tool for estimating 20-year dementia risk in the general population based on a midlife risk profile. To investigate the associations between CAIDE score and dementia-related brain changes up to 30 years later on magnetic resonance imaging (MRI). Participants in the Cardiovascular Risk Factors, Aging and Dementia (CAIDE) study were derived from random, population-based samples surveyed in 1972, 1977, 1982, or 1987. A first re-examination was conducted in 1998, and a second re-examination in 2005-2008 (total follow-up time up to 30 years). The MRI study population included 112 individuals with MRIs from the first re-examination, and a different group of 69 individuals with MRIs from the second re-examination. MRIs from 1998 were used to determine gray matter volume, and to visually rate white matter hyperintensities (WMH) of presumed vascular origin and medial temporal lobe atrophy (MTA). MRIs from 2005-2008 were used to assess cortical thickness, gray matter and WMH volume, and to visually rate MTA. CAIDE scores were calculated for participants in both re-examinations based on midlife sociodemographic and vascular factors and additionally apolipoprotein E status. Higher midlife CAIDE score was associated with more severe WMH 20 years later: RR (95% CI) was 1.69 (1.15-2.08); and with higher WMH volume (β 0.27, p = 0.036) and higher MTA score (RR 1.91, 95% CI 1.16-2.34) up to 30 years later. CAIDE Dementia Risk Score in midlife was most consistently associated with WMH later in life. A relation with MTA was observed in individuals with longer follow-up time.