Choroid plexus volume in Parkinson’s disease: a systematic review and meta-analysis

Parkinson’s disease (PD) is a neurodegenerative disorder marked by impairments in motor abilities and cognitive functions. Emerging evidence indicates that alterations in choroid plexus volume (CPV) may contribute to disease progression, potentially by influencing protein accumulation and clearance in the brain. Nevertheless, the evidence regarding CPV alterations and their various relationships has not been comprehensively elucidated and remains inconclusive. This review aimed to compare overall CPV between PD patients and healthy controls (HCs), and to summarize its associations with various features of PD patients. PubMed, Scopus, Embase, and Web of Science were searched up to May 2, 2026. Eligible studies assessed CPV using structural magnetic resonance imaging (MRI) and reported either group comparisons or associations with PD-related characteristics. Meta-analysis was performed using standardized mean differences in R version 4.4.0, and narrative synthesis was used for non-poolable findings. Twenty studies satisfied the predefined inclusion criteria; however, the quantitative meta-analysis was performed using data from eight studies with available comparable outcomes. The meta-analysis revealed significantly larger normalized CPV in PD patients than HCs (SMD = 0.42, 95%CI 0.12 to 0.72, I 2 =91%, p < 0.01). Furthermore, narrative synthesis showed that increased CPV was also associated with greater motor impairment, cognitive decline, poorer levodopa responsiveness, glymphatic dysfunction, neuroimaging abnormalities, and cerebrospinal fluid biomarkers. Current evidence suggests that CPV may be increased among PD patients and represents a potential non-invasive marker of neuroinflammatory and neurodegenerative processes in PD. Further longitudinal multicenter studies are needed to determine its mechanistic and prognostic significance.