Allostatic load, a measure of cumulative physiological stress, impairs brain structure but not β-accumulation in older adults: an exploratory study.

INTRODUCTION

Allostatic load (AL) is a composite score of progressive physiological dysregulations in response to long-term exposure to everyday stress. Despite growing interest, limited research has focused on links with cerebral and cognitive aspects of aging and with markers sensitive to Alzheimer's disease (AD) in a healthy elderly population and with a multimodal approach.

METHODS

At baseline, 111 older adults (without cognitive impairment) from the Age-Well trial completed blood and anthropometric markers collection, cognitive assessments and multimodal neuroimaging within 3 months.

RESULTS

AL was negatively associated with gray matter volume and white matter integrity within frontal and temporal regions and poorer attentional performance.

DISCUSSION: AL is linked to structural brain integrity in aging- and stress-sensitive regions but not with AD-related markers (β-amyloid load) and only in two AD-sensitive brain regions in older adults. These results highlight the potential interest of AL as a sensitive index of stress-induced brain aging.