Preliminary data from midlife cardiac and vascular phenotyping and white matter at age 70: the population-based 1946 British Birth Cohort

Abstract

Introduction: Data drawn from the 1946 British birth cohort is opportunistically placed to address how midlife cardiac and vascular structure is linked with white matter brain health later in life, given that participants are born in the same week; had detailed cardiovascular phenotyping at age 60; MRI scans at age 70; and have many measured confounders. We assess if, and to what extent, midlife cardiac and vascular phenotypes are related to white matter brain health at age 70. Methods: At age 60-64, participants from the British 1946 birth cohort underwent echocardiography (left ventricular mass (LVM), LV end diastolic dysfunction (LVEDV) and relative wall thickness (RWT)); carotid to femoral pulse wave velocity (PWV, indicator of arterial stiffness) and common carotid intima-media thickness (cIMT, indictator of atherosclerosis). At age 70, a sub-sample underwent MRI and DTI (n=468, 49% female). Regression analyses examined associations between cardiovascular phenotypes and later-life indexes of brain health including white matter hyperintensity (WMH) volume and normal appearing white matter (NAWM) DTI metrics indexing microstructural integrity, adjusting for sex, scan age, childhood cognition, education, and childhood socioeconomic position. Effect modification by sex and APOE-ε4 were examined. Results: Preliminary data demonstrates weak evidence for an overall direct relationship between cardiovascular phenotyping at age 60 and WMH volume at age 70 (all p>0.05). However, there is evidence that LVM and LVEDV at age 60 are associated with poorer NAWM microstructural integrity at age 70, particularly in women. Discussion: We provide preliminary evidence of differential features of midlife cardiac and phenotypic health with WMH and microstructural integrity 10 years later.