Dietary magnesium supplementation in cats with chronic kidney disease: A prospective double-blind randomized controlled trial

Tang, PK; van den Broek, DHN; Jepson, RE; Geddes, RF; Chang, YM; Loetter, N; Moniot, D; Biourge, V; Elliott, J

Abstract

Background: Plasma total magnesium concentration (tMg) is a prognostic indicator in cats with chronic kidney disease (CKD), shorter survival time being associated with hypomagnesemia. Whether this risk factor is modifiable with dietary magnesium supplementation remains unexplored. Objectives: Evaluate effects of a magnesium-enriched phosphate-restricted diet (PRD) on CKD-mineral bone disorder (CKD-MBD) variables. Animals: Sixty euthyroid client-owned cats with azotemic CKD, with 27 and 33 allocated to magnesium-enriched PRD or control PRD, respectively. Methods: Prospective double-blind, parallel-group randomized trial. Cats with CKD, stabilized on a PRD, without hypermagnesemia (tMg >2.43 mg/dL) or hypercalcemia (plasma ionized calcium concentration, (iCa) >6 mg/dL), were recruited. Both intention-to-treat and per-protocol (eating >= 50% of study diet) analyses were performed; effects of dietary magnesium supplementation on clinicopathological variables were evaluated using linear mixed effects models. Results: In the per-protocol analysis, tMg increased in cats consuming a magnesium-enriched PRD (beta, 0.25 +/- .07 mg/dL/month; P < .001). Five magnesium supplemented cats had tMg >2.92 mg/dL, but none experienced adverse effects. Rate of change in iCa differed between groups (P = .01), with decreasing and increasing trends observed in cats fed magnesium-enriched PRD and control PRD, respectively. Four control cats developed ionized hypercalcemia versus none in the magnesium supplemented group. Log-transformed plasma fibroblast growth factor-23 concentration (FGF23) increased significantly in controls (beta, 0.14 +/- .05 pg/mL/month; P = .01), but remained stable in the magnesium supplemented group (beta, 0.05 +/-.06 pg/mL/month; P =.37). Conclusions and Clinical Importance: Magnesium-enriched PRD is a novel therapeutic strategy for managing feline CKD-MBD in cats, further stabilizing plasma FGF23 and preventing hypercalcemia.

Citation

Tang, P., van den Broek, D., Jepson, R., Geddes, R., Chang, Y., Loetter, N., Moniot, D., Biourge, V., & Elliott, J. (2024). Dietary magnesium supplementation in cats with chronic kidney disease: A prospective double-blind randomized controlled trial. Journal of Veterinary Internal Medicine, https://doi.org/10.1111/jvim.17134

• Journal Article Type: Article
• Acceptance Date: May 31, 2024
• Online Publication Date: Jul 1, 2024
• Publication Date: 2024
• Deposit Date: Jul 19, 2024
• Publicly Available Date: Jul 19, 2024
• Journal: Journal of Veterinary Internal Medicine
• Print ISSN: 0891-6640
• Electronic ISSN: 1939-1676
• Publisher: Wiley Open Access
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1111/jvim.17134
• Keywords: anti-calcemic; calcium; CKD-MBD; fibroblast growth factor-23; hypercalcemia; magnesium oxide; INTIMA-MEDIA THICKNESS; GROWTH-FACTOR 23; HEMODIALYSIS-PATIENTS; SERUM MAGNESIUM; INTESTINAL-ABSORPTION; CALCIUM-ABSORPTION; PHOSPHATE; BONE; CALCIFICATION; METAANALYSIS