Abstract: TH-PO1126
Association of Protein Intake with Serum Sodium Concentration in CKD
Session Information
- CKD: Therapies, Innovations, and Insights
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2302 CKD (Non-Dialysis): Clinical, Outcomes, and Trials
Authors
- Shah, Syed Muhammad Obaida M, The University of Tennessee Health Science Center College of Medicine, Memphis, Tennessee, United States
- Ramrattan, Amit, The University of Tennessee Health Science Center College of Medicine, Memphis, Tennessee, United States
- Kovesdy, Csaba P., The University of Tennessee Health Science Center College of Medicine, Memphis, Tennessee, United States
- Wall, Barry M., The University of Tennessee Health Science Center College of Medicine, Memphis, Tennessee, United States
- Hussein, Wael F., The University of Tennessee Health Science Center College of Medicine, Memphis, Tennessee, United States
Background
Low dietary protein intake can impair free water excretion and predispose to hyponatremia. The urine urea nitrogen-to-creatinine ratio (UUNCR) provides a practical surrogate of dietary protein intake. We examined the association between UUNCR and serum sodium concentration (SNa) in patients with non-dialysis dependent chronic kidney disease (CKD).
Methods
We conducted a retrospective longitudinal cohort study in outpatient veterans with eGFR <60 ml/min/1.73m2 at a single institution. UUNCR was calculated from spot morning urine samples obtained at each clinic visit. SNa was categorized based on physiological cutoffs (≤135, 136–145, and ≥146 mmol/L). Associations between UUNCR and SNa were analyzed using mixed effect models.
Results
Among 631 patients (mean age 67.5 ± 10.6, 96.8% male) we recorded a total of 2,846 UUNCR/SNa measurements (median 4, IQR: 2-7) over a median follow-up time of 6.4 years. SNa <= 135 was present in 6.5% of patients and was more common among those with active cancer and liver disease. Mean UUNCR was slightly higher among hyponatremic patients (6.27) compared to normonatremic (5.59) and hypernatremic (6.13) patients, but this difference was not statistically significant (p=0.061). In mixed effect models adjusting for age, sex, race, BMI, blood pressure, comorbidities including liver disease, eGFR, proteinuria, cancer and medication use, UUNCR was not significantly associated with SNa (p= 0.48).
Conclusion
We found no significant association between protein intake, as estimated by UUNCR, and SNa among CKD patients, suggesting that solute intake may not be a key driver of hyponatremia in this patient population. Further investigation is needed to determine whether protein intake affects the relationship between hyponatremia and patient outcomes in CKD.