Association between the choroid plexus volume and cognitive function in community-dwelling older adults without dementia: A population-based cross-sectional analysis

ABSTRACT Background Choroid plexus (CP) volume increase may be associated with cognitive decline in older individuals without dementia. In this study, we aimed to clarify whether CP volume can be an imaging marker of cognitive decline in older adults, verify its association with cognitive decline in older individuals compared with brain parenchymal and CSF volumes, and explore the factors associated with the CP volume. Methods We measured the CP volume, brain parenchyma, and cerebrospinal fluid (CSF) spaces associated with disproportionately enlarged subarachnoid space hydrocephalus (DESH), an imaging feature of normal-pressure hydrocephalus, in community-dwelling individuals aged ≥65 years without dementia. Results In 1,370 participants, lower Mini-Mental State Examination (MMSE) scores were significantly associated with higher CP volume, even after adjusting for DESH-related CSF space and brain parenchymal volume. CP volume was more strongly associated with MMSE scores than DESH-related CSF space and brain parenchymal volume. History of smoking, white matter hyperintensity, enlarged perivascular spaces, age, body mass index, and diabetes mellitus were associated with increased CP volume. Conclusions In community-dwelling older individuals without dementia, CP volume is associated with cognitive decline independent of the brain parenchyma and CSF volumes and may be one of the most sensitive imaging markers of cognitive decline. Our findings emphasize the importance of investigating CP volume increase to maintain cognitive function in older individuals. Further longitudinal studies are required. WHAT IS ALREADY KNOWN ON THIS TOPIC Choroid plexus (CP) volume increase has been associated with cognitive decline in older individuals without dementia; however, the influence of volumes of cerebrospinal fluid (CSF) and brain parenchyma in this association remains unexplored. The extent to which CP volume is involved in cognitive decline in older adults compared with brain parenchymal and CSF volumes is unclear. WHAT THIS STUDY ADDS CP volume is associated with cognitive decline in older individuals independent of the volumes of CSF and brain parenchyma. CP is one of the structures most closely related to cognitive impairment in older individuals without dementia. HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY Our study provides a reference for investigating CP volume increase to maintain cognitive function in older individuals.