Abstract: TH-PO1110
Protective Phosphorus Ranges for Major Adverse Cardiovascular Events in CKD: Insights from Spline-Based Survival Models
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
- Vanteru, Abinay Siva kumar Reddy, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States
- Nemalidinne, Krishna Vani, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States
- Nemalidinne, Kiran Reddy, Rutgers The State University of New Jersey, New Brunswick, New Jersey, United States
- Karakala, Nithin, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States
- Arthur, John M., University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States
Background
Serum phosphorus is linked to cardiovascular risk in chronic kidney disease (CKD), but the optimal range for minimizing major adverse cardiovascular events (MACE), particularly across different age groups, remains unclear. This study investigated the nonlinear relationship between serum phosphorus levels and MACE in two distinct age groups.
Methods
We analyzed 10 years of lab data from CKD stage 3a–5 patients, using the CKD-EPI 2021 equation to recalculate eGFR. Age-stratified Cox models with natural cubic splines assessed nonlinear associations between serum phosphorus and MACE. To further characterize this relationship, we used the Spline-based survival models to estimate Hazard ratios across a continuous phosphorus range.
Results
Analyses were conducted separately for individuals aged, younger<60 years (n = 4154) and elderly, ≥60 years (n = 8183), after excluding records with missing data. Serum phosphorus was significantly associated with MACE risk in both age groups. Among individuals aged <60 years, hazard ratios (HRs) for the spline terms were 4.02 (95% CI: 3.65–4.44), 2.39 (1.80–3.17), and 7 (4.45–11.02), all p < 0.001. In the ≥60 age group, HRs were 4.31 (3.95–4.70), 0.40 (0.31–0.52),and 1.45 (1.02–2.06), all p < 0.05. Model concordance was modest (0.546 for <60, 0.549 for ≥60). Survival analysis on Spline-based Cox model predictions demonstrated that serum phosphorus levels between 2.3–4.1 mg/dL were associated with the lowest MACE risk (HR < 1) in individuals aged ≥60, while a comparatively, broader protective range of 2.0–4.5 mg/dL was observed in those <60. Risk increased nonlinearly beyond these thresholds in both groups.
Conclusion
Serum phosphorus demonstrates a nonlinear association with MACE risk in patients with CKD stages 3a–5, with elevated risk at extreme levels in both age groups. However, the optimal protective range differed by age, highlighting the need for age-specific phosphorus targets to reduce cardiovascular events in this population.