Brain atrophy in peritoneal dialysis and CKD stages 3-5: A cross-sectional and longitudinal study

Background Brain atrophy has been reported in patients with end-stage renal disease receiving hemodialysis, although its mechanism is unknown. However, little is known regarding brain atrophy in patients receiving peritoneal dialysis (PD). Therefore, we examined brain volume and its annual change over 2 years in PD patients compared with patients with non–dialysis-dependent chronic kidney disease (NDD-CKD). Study Design Cross-sectional and longitudinal cohort. Setting & Participants 62 PD patients and 69 patients with NDD-CKD with no history of cerebrovascular disease who underwent brain magnetic resonance imaging (MRI) were recruited in a cross-sectional study. Among them, 34 PD patients and 61 patients with NDD-CKD, who underwent a second brain MRI after 2 years, were recruited in a longitudinal study. Predictor PD therapy versus NDD-CKD. Outcomes & Measurements T1-weighted magnetic resonance images were analyzed. Total gray matter volume (GMV), total white matter volume (WMV), and cerebrospinal fluid space volume were segmented, and each volume was quantified using statistical parametric mapping software. Normalized GMV and WMV values were calculated by division of GMV and WMV by intracranial volume to adjust for variations in head size. We compared normalized GMV and normalized WMV between PD patients and patients with NDD-CKD in the cross-sectional study and the annual change in normalized GMV in the longitudinal study. Results In the cross-sectional study, normalized GMV, which was correlated inversely with age, was lower in PD patients than in patients with NDD-CKD. However, normalized WMV, which was not correlated with age, was comparable between the groups. Annual change in normalized GMV was significantly higher in PD patients than in patients with NDD-CKD. These differences remained significant even after adjustment for potential confounding factors. Limitations A short observation period and high dropout rate in the longitudinal study. Conclusions Decline in normalized GMV is faster in PD patients than in patients with NDD-CKD.