Glymphatic dysfunction and choroid plexus volume increase in older adults with poor sleep quality

Objective This study aimed to explore alterations in diffusion tensor image analysis along the perivascular space (DTI-ALPS) method and choroid plexus volume (CPV), which could be biomarkers of the glymphatic system in older adults with poor sleep quality (PSQ). Methods Fifty-two Japanese older adults with Pittsburgh Sleep Quality Index (PSQI) scores > 5 (22 men and 30 women; mean age ± SD = 73.10 ± 5.67 years) and 52 healthy controls (HCs; PSQI score ≤ 5) were included. Diffusion-weighted imaging (DWI) and 3D T1-weighted images were obtained using 3T magnetic resonance imaging. The ALPS index was calculated using preprocessed diffusion-weighted imaging (DWI), and the CPV was calculated using FreeSurfer 6.0. The mean ALPS index was subsequently compared between the PSQ group and HCs by using a general linear model (GLM) adjusted for covariates, including age, sex, years of education, intracranial volume, systolic blood pressure, diastolic blood pressure, hemoglobin A1c, and white matter lesion volume (WMLV). The CPV was also compared between the two groups by using the GLM, adjusting for the same covariates mentioned above. Next, we conducted a partial correlation analysis between the ALPS index and the CPV, Montreal Cognitive Assessment (MoCA), and PSQI scores, adjusting for all the abovementioned covariates. Results Compared with HCs, patients in the PSQ group had a significantly lower mean ALPS ( p  = 0.04, Cohen’s d  = − 0.28) and a greater CPV ( p  = 0.11, Cohen’s d  = 0.24). In the PSQ group, the mean ALPS score was significantly negatively correlated with the CPV ( r  = − 0.35, false discovery rate [FDR]-corrected p  = 0.03) but was significantly positively correlated with the MoCA score ( r  = 0.35, FDR-corrected p  = 0.03). Conclusion Older adults with PSQ exhibited a decrease in the glymphatic system and an increase in CPV.