ArticleNPJ Parkinson's disease2025
A systematic review and meta-analysis on glymphatic flow dysfunction in Parkinson's disease and Parkinsonism spectrum.
Article in NPJ Parkinson's disease, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 1 of them a synthesis that pooled it.
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Who cites it
14 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Glymphatic Pathway Dysfunction in Mild Cognitive Impairment: A Systematic Review and Meta-Analysis Using Diffusion Tensor Imaging Along the Perivascular Space.CNS neuroscience & therapeutics · 2025Pooled it
- Brain Clearance of Contrast Agent in Intravenous DCE-MRI Is Measurable and Cannot Be Explained by Clearance Across the BBB Alone.Magnetic resonance in medicine · 2026Article
- High-Resolution IVIM MRI Characterizes Diffusion-Perfusion Properties of the Parasagittal Dura.NMR in biomedicine · 2026Article
- Glymphatic function in humans: indicators, modulators, and measurement strategies.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2026Review
- Diffusion tensor image analysis along the perivascular space (DTI-ALPS): redefining its interpretation and role.Japanese journal of radiology · 2026Review
- Glymphatic dysfunction in cerebellar neurodegeneration: mechanistic insights and emerging clinical implications.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2026Review
- Time vortex: the circadian-dopaminergic dialogue in Parkinson's disease.NPJ Parkinson's disease · 2026Review
- Association of the DTI-ALPS index with motor and non-motor symptoms in Parkinson's disease with postural instability/gait difficulty: a diffusion tensor MRI study.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2026Article
- From phenotype to biology: a multi-modal roadmap of biofluid, tissue, imaging, and digital biomarkers in Parkinson's disease.Translational neurodegeneration · 2026Review
- Longitudinal Neuroimaging Reveals Divergent Clinical Associations of Glymphatic Dysfunction and Dopaminergic Degeneration in Parkinson's Disease.Human brain mapping · 2026Article
- Review
- Alterations of cerebrospinal fluid flow dynamics in Parkinson's disease.NPJ Parkinson's disease · 2026Article
- Article
- Free water-mediated associations among choroid plexus enlargement, white matter lesions, and cognitive performance in type 2 diabetes mellitus.Frontiers in endocrinology · 2026Article
Corrections and comments
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Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
This systematic review and meta-analysis synthesized evidence of glymphatic dysfunction in Parkinson's disease (PD) and related Parkinsonian syndromes using the diffusion tensor imaging along the perivascular space (DTI-ALPS) index. Following the PRISMA 2020 guidelines, 28 studies published up to May 12, 2025, were included. The primary meta-analysis of 21 studies (1678 patients with PD and 1088 HCs) demonstrated a significant reduction in the DTI-ALPS index in patients with PD (Cohen's d = -0.57; 95% CI: -0.67 to -0.47; p < 0.001), indicating moderate glymphatic dysfunction. This impairment was significantly associated with clinical progression, including longer disease duration (β = -0.08, p = 0.005) and higher Hoehn and Yahr (H-Y) stages (β = -0.18, p = 0.057). This association was particularly strong in patients with early-stage PD (H-Y < 2.5). Phenotypic analyses revealed a gradient of dysfunction, with the most severe impairment found in patients with PD with dementia (Glass's Δ = -1.04) and atypical Parkinsonian syndromes (Δ = -1.01). Technical subgroup analyses showed consistent findings, with region-of-interest size significantly moderating effect size (p = 0.04). The methodological quality of the included studies was high, with no evidence of publication bias. The methodological quality was high, with no evidence of publication bias (p ≥ 0.88). These findings underscore the progressive glymphatic decline with PD severity and duration, independent of age or cognition, and highlight distinct impairment patterns across different clinical phenotypes.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.