Kidney Week

Abstract: FR-PO0315

Efficacy of High Dialysate Magnesium on Parathyroid Hormone in Patients with ESKD: A Multicenter Randomized Controlled Trial

Session Information

• CKD-MBD: Mechanistic Insights and Management
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 502 Bone and Mineral Metabolism: Clinical

Authors

• Ekpanithanpong, Amonrat, Bhumiboladulyadej Hospital, Bangkok, Thailand

Amonrat Ekpanithanpong, MD

• Jintanapramote, Kavita, Bhumiboladulyadej Hospital, Bangkok, Thailand

Kavita Jintanapramote, MD

• Kiattisunthorn, Kraiwiporn, Siriraj Medical School, Mahidol University, Bangkok, Thailand

Kraiwiporn Kiattisunthorn, MD

• Ampong, Sompong, Bhumiboladulyadej Hospital, Bangkok, Thailand

Sompong Ampong, RN

• Suwannatrai, Chatanan, Bhumiboladulyadej Hospital, Bangkok, Thailand

Chatanan Suwannatrai, RN

• Chawaratthanakul, Karanpol, Chandrubeksa Hospital, Kamphaeng Saen, Nakhon Pathom, Thailand

Karanpol Chawaratthanakul, MD

• Seetatand, Supawadee, Chandrubeksa Hospital, Kamphaeng Saen, Nakhon Pathom, Thailand

Supawadee Seetatand, RN

• Srito, Worawalan, Thasaminthrathirat Hospital, Bangkok, Thailand

Worawalan Srito, RN

• Keepong, Junyaporn, CGH Phaholyothin Hospital, Bangkok, Thailand

Junyaporn Keepong, RN

• Homkrailas, Piyavadee, Bhumiboladulyadej Hospital, Bangkok, Thailand

Piyavadee Homkrailas, MD

Background

Hyperparathyroidism is a common complication in end-stage kidney disease (ESKD), associated with adverse clinical outcomes. Treatment options remain limited. Increasing dialysate magnesium has been proposed as a strategy to modulate parathyroid hormone (PTH) secretion and mineral metabolism, but randomized clinical evidence remains limited.

Methods

We conducted a multicenter, randomized, single-blind controlled trial evaluating the effect of increasing dialysate magnesium from 1.0 to 2.0 mEq/L over 12 weeks in maintenance hemodialysis patients. The primary outcome was percent change in intact PTH (iPTH) from baseline to week 12. Secondary outcomes included alkaline phosphatase (ALP), fibroblast growth factor 23 (FGF23), and inflammatory markers. Analyses were performed using log-scale ANCOVA adjusted for baseline PTH and sex, with prespecified exploratory subgroup analyses according to time-averaged phosphate, calcium and baseline PTH.

Results

Among 100 randomized patients, 92 completed the study. Increasing dialysate magnesium did not significantly reduce iPTH overall versus standard dialysate magnesium (−11.0%; 95% CI, −30.0% to 14.0%; p=0.365). However, exploratory subgroup analyses showed greater PTH reduction in patients with controlled mineral metabolism (mean phosphate 2.5–4.5 mg/dL and calcium 8.5–10.5 mg/dL), with the largest effect observed in those with baseline PTH ≥300 pg/mL (−38.9%; 95% CI, −59.4% to −8.1%; p=0.021), although no significant interaction was detected. FGF23 showed a similar directional reduction (−17.0%; p=0.050), while ALP and inflammatory markers were unchanged. Increased dialysate magnesium was well tolerated, with no treatment-related serious adverse events.

Conclusion

Increasing dialysate magnesium did not significantly reduce PTH overall. However, exploratory analyses indicate a context-dependent effect, with greater benefit in patients with well-controlled calcium and phosphate. These findings support magnesium as a safe adjunctive strategy in CKD–mineral and bone disorder management.

Funding

• Commercial Support – GRACE WATER MED CO., LTD Thailand