Choroid plexus volume, cognitive spectrum, and biomarkers of brain aging in older adults: The MIND‐China MRI Study.

Background: The choroid plexus (CP) is a major source of cerebrospinal fluid (CSF) production that has been involved in clearance of CSF proteins and regulation of brain function, and possibly, in the pathogenesis of Alzheimer's dementia. However, population‐based studies have not yet investigated the associations of CP volume with cognitive function and biomarkers of pathological brain aging in older adults. Method: This population‐based cross‐sectional study included 1220 older adults (age ≥60 years) derived from the Multimodal INterventions to delay Dementia and disability in rural China, who underwent structural brain magnetic resonance imaging scans. CP was automatically segmented and quantified on 3T structural T1‐weighted images. Cognitive function was assessed using a neuropsychological test battery. Dementia, Alzheimer's disease (AD), and mild cognitive impairment (MCI) were diagnosed following the international criteria. In the subsample (n = 905), we measured plasma amyloid beta (Aβ)40, Aβ42, total tau, and neurofilament light chain (NfL) using the Simoa platform. Data were analyzed with logistic and the general linear regression models. Result: In the total sample (n = 1220), 275 persons were diagnosed with MCI (22.54%), 30 with all‐cause dementia (2.46%), and 26 with AD (2.13%). Controlling for demographics, total intracranial volumes (ICV), cardiovascular risk factors and related disorders, and APOE genotype, larger CP volume was significantly associated with increased likelihoods of dementia (adjusted odds ratio = 2.12; 95% CI = 1.33‐3.36), AD (2.28; 1.37‐3.80), and MCI (1.27; 1.07‐1.50). In addition, larger CP volume was significantly associated with lower z‐scores of verbal fluency, executive function, and global cognition (p<0.05). Furthermore, larger CP volume was associated with smaller volumes of total gray matter and hippocampus, and greater volumes of lateral ventricles, global white matter hyperintensity (WMH), and periventricular WMH (p<0.05). In the plasma subsample, larger CP volume was significantly associated with higher plasma Aβ42 concentration (p<0.05), and marginally with higher plasma Aβ40 concentration (p = 0.07). Conclusion: Large CP volume is associated with poor performance across the cognitive continuum as well as with biomarkers of cerebral atrophic, neurodegenerative, and microvascular lesions in older adults. [ABSTRACT FROM AUTHOR]