Cardiometabolic disease, cognitive decline, and brain structure in middle and older age

Abstract INTRODUCTION The presence of multiple cardiometabolic diseases (CMDs) has been linked to increased dementia risk, but the combined influence of CMDs on cognition and brain structure across the life course is unclear. METHODS In the UK Biobank, 46,562 dementia‐free participants completed a cognitive test battery at baseline and a follow‐up visit 9 years later, at which point 39,306 also underwent brain magnetic resonance imaging. CMDs (diabetes, heart disease, and stroke) were ascertained from medical records. Data were analyzed using age‐stratified (middle age [< 60] versus older [≥ 60]) mixed‐effects models and linear regression. RESULTS A higher number of CMDs was associated with significantly steeper global cognitive decline in older (β = –0.008; 95% confidence interval: −0.012, −0.005) but not middle age. Additionally, the presence of multiple CMDs was related to smaller total brain volume, gray matter volume, white matter volume, and hippocampal volume and larger white matter hyperintensity volume, even in middle age. DISCUSSION CMDs are associated with cognitive decline in older age and poorer brain structural health beginning already in middle age. Highlights We explored the association of CMDs with cognitive decline and brain MRI measures. CMDs accelerated cognitive decline in older (≥60y) but not middle (<60) age. CMDs were associated with poorer brain MRI parameters in both middle and older age. Results highlight the connection between CMDs and cognitive/brain aging.