Kidney Week

Abstract: FR-PO0271

Association Between Hemoglobin A1c Levels and Phosphate Regulation in CKD: The CRIC Study

Session Information

• Bone and Mineral Metabolism: Clinical Epidemiology and Outcomes
  November 07, 2025 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 502 Bone and Mineral Metabolism: Clinical

Authors

• Kwon, Alvin Guyun, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Alvin Guyun Kwon, MD, MPH

• He, Jiang, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Jiang He, MD, PhD

• Hamm, L. Lee, Tulane University, New Orleans, Louisiana, United States

L. Lee Hamm, MD

• Geng, Siyi, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Siyi Geng, MS

• Moe, Orson W., The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Orson W. Moe, MD

• Maalouf, Naim M., The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Naim M. Maalouf, MD

• Sakhaee, Khashayar, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Khashayar Sakhaee, MD

• Zechner, Christoph, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Christoph Zechner, MD, DrMed

• Lederer, Eleanor D., The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Eleanor D. Lederer, MD, FASN

• Van Buren, Peter N., The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Peter N. Van Buren, MD, MS

• Toto, Robert D., The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Robert D. Toto, MD

• Vazquez, Miguel A., The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Miguel A. Vazquez, MD, FASN

• Chen, Jing, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Jing Chen, MD, MS, MSc, FASN

Group or Team Name

• CRIC Study Investigators.

Background

Medial arterial calcification (MAC) is common in diabetes and CKD, contributing to elevated cardiovascular disease (CVD) risk, with phosphate as a key factor. While elevated phosphorus and fibroblast growth factor 23 (FGF23) have been reported in diabetes, the link between HbA1c and phosphate homeostasis in CKD remains unclear. We analyzed associations between HbA1c and homeostasis in a large CKD cohort.

Methods

This analysis included 3,865 participants with CKD from the Chronic Renal Insufficiency Cohort (CRIC) Study after excluding 134 participants with missing data. Linear regression assessed cross-sectional associations of HbA1c with serum phosphate, calcium, FGF23, alkaline phosphatase (ALP), and PTH, adjusting for age, sex, black, center-sites, education, current smoker, calories/day, diabetes status, CVD, body mass index, eGFR, hemoglobin, use of ACE inhibitors, ARB, and vitamin D, and 24-hour urine creatinine.

Results

The average age of participants was 58 years; the mean eGFR was 44 mL/min/1.73 m^2; and the mean hemoglobin level was 12.6 g/dL After multiple adjustments, HbA1c was significantly and positively associated with serum phosphorus, ALP, and FGF23 (Table). However, HbA1c was not significantly associated with PTH and calcium.

Conclusion

In CKD patients, HbA1c levels were independently associated with elevated serum phosphorus, ALP, and FGF23 levels, all which are associated with vascular calcification and bone disorders. The potential role of glucose-mediated phosphate dysregulation in contributing to vascular calcification and bone disorders needs to be confirmed in future studies.

Association of a One-SD (1.56%) Increase in Hemoglobin A1c Levels with Significant Phosphate-Related Biomarkers

Digital Object Identifier (DOI)

• doi: 10.1681/ASN.2025mzt4jn36