Association between serum magnesium levels and cognitive function in patients undergoing hemodialysis.

Background: The relationship between chronic kidney disease-mineral and bone disorder (CKD-MBD) and cognitive function remains largely unknown. This cross-sectional study aimed to explore the association between CKD-MBD and cognitive function in patients on hemodialysis.
Methods: Hemodialysis patients aged ≥ 65 years without diagnosed dementia were included. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE). CKD-MBD markers, serum magnesium, intact parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OHD), fibroblast growth factor (FGF)-23, and soluble α-klotho were measured.
Results: Overall, 390 patients with a median age of 74 (interquartile range, 70-80) years, mean serum magnesium level of 2.4 ± 0.3 mg/dL, and median MoCA and MMSE scores of 25 (22-26) and 28 (26-29), respectively, were analyzed. MoCA and MMSE scores were significantly higher (preserved cognitive function) in the high-magnesium group than in the low-magnesium group according to the unadjusted linear regression analysis (β coefficient [95% confidence interval (CI)] 1.05 [0.19, 1.92], P = 0.017 for MoCA; 1.2 [0.46, 1.94], P = 0.002 for MMSE) and adjusted multivariate analysis with risk factors for dementia (β coefficient [95% CI] 1.12 [0.22, 2.02], P = 0.015 for MoCA; 0.92 [0.19, 1.65], P = 0.014 for MMSE).
Conclusions: Higher serum magnesium levels might be associated with preserved cognitive function in hemodialysis patients. Conversely, significant associations were not observed between cognitive function and intact PTH, 25-OHD, FGF-23, or soluble α-klotho levels.
Competing Interests: Declarations Conflicts of interest The authors have declared that no conflict of interest exists. Ethical approval All procedures were performed in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The institutional review board of our hospital (Approval No.: 33–183(10800)) approved the study. Informed consent Informed consent was obtained from all individual participants included in the study.
(© 2024. The Author(s), under exclusive licence to Japanese Society of Nephrology.)