Choroid plexus volume in pathology-confirmed Alzheimer's disease.

INTRODUCTION: The choroid plexus (CP) increases in volume across the Alzheimer's disease (AD) continuum, suggesting its potential as a clearance-related biomarker. However, few studies have examined ante-mortem CP volume in relation to post-mortem AD pathology, the gold standard for diagnosis. METHODS: Participants who had structural magnetic resonance imaging and post-mortem pathology, with an interval of ≤ 5 years between imaging and death, were examined. Normalized CP volume (NCPV) was semi-automatically segmented from the lateral ventricles and analyzed using Bayesian linear regression to estimate associations with cognitive impairment (CI), AD pathology, and relevant clinical/demographic data. RESULTS: Intermediate and high levels of AD pathology and CI were associated with larger NCPV, whereas female sex was associated with lower NCPV. Subgroup analyses showed larger NCPV in individuals with greater CI despite comparable levels of AD pathology. DISCUSSION: These findings link CP enlargement to neuropathologically confirmed AD burden and CI, supporting further investigation of CP structure and function in AD.