Glymphatic Pathway Dysfunction in Severe Obstructive Sleep Apnea: A Meta-Analysis Publisher Pubmed

Summary: Does sleep apnea harm the brain? Meta-analysis finds lower DTI-ALPS in severe OSA, signaling glymphatic issues. #ObstructiveSleepApnea #GlymphaticSystem

Ghaderi S^{1, 2} ; Mohammadi S¹ ; Fatehi F¹
Source: Sleep Medicine Published:2025

Abstract

Background: Obstructive sleep apnea (OSA), a sleep disorder, is associated with cognitive decline and is potentially linked to glymphatic system dysfunction. This meta-analysis investigates glymphatic function in severe OSA (apnea-hypopnea index ≥30) using the Diffusion Tensor Imaging Analysis along the Perivascular Space (DTI-ALPS) index. Methods: This study followed PRISMA guidelines for systematic reviews and meta-analyses. A comprehensive search of PubMed, Web of Science, Scopus, and Embase was conducted from inception to January 20, 2024. Studies investigating the ALPS index in OSA using DTI were included. Analyses included a random-effects meta-analysis, sensitivity analysis, meta-regression, publication bias evaluation (funnel plot, Egger's test, and Begg's test), and risk of bias assessment. Results: Systematic review identified four studies (137 patients with severe OSA and 170 healthy controls (HCs)). Pooled analysis revealed a significant reduction in the DTI-ALPS index in severe OSA patients compared to HCs (standardized mean difference: −0.95, 95 % CI: −1.46 to −0.44, p < 0.001), indicating impaired glymphatic function. Heterogeneity was moderate to high (I2 = 76.07 %), but sensitivity analyses confirmed robustness. Meta-regression analyses identified the sources of heterogeneity as the apnea-hypopnea index (β = −0.039, p = 0.009) and the Epworth Sleepiness Scale (β = −0.150, p = 0.032), with no effects observed for age or male ratio. Qualitative (funnel plot) and quantitative publication bias assessments (Egger's and Begg's tests) showed no significant bias, and risk of bias evaluations using the Newcastle-Ottawa Scale indicated high methodological quality across studies. Conclusions: These findings suggest that severe OSA disrupts glymphatic activity. The DTI-ALPS index emerges as a promising tool for assessing glymphatic dysfunction in OSA. © 2025 Elsevier B.V.