Elevated Calcium-Phosphate Product (CPP) in Chronic Kidney Disease (CKD): A Silent Predictor of Poor PCI (Percutaneous Coronary Intervention) Outcomes: A Propensity Score Matched Analysis

Abstract Background An elevated calcium-phosphate product (CPP), defined as a product of serum calcium and serum phosphate, is a hallmark of CKD-mineral and bone disorder and has been implicated in accelerated coronary artery calcification, arterial stiffness, and left ventricular hypertrophy. These pathological changes contribute to adverse cardiovascular outcomes. While prior studies have shown worse percutaneous coronary outcomes (PCI) outcomes in CKD patients overall, the prognostic impact of CPP levels remains underexplored. The objective is to evaluate post-PCI outcomes in CKD patients with and without hypercalcemia and hyperphosphatemia. Methods A retrospective cohort analysis was conducted using the TriNetX U.S. Collaborative Network, focusing on adult patients with CKD undergoing PCI. Patients were grouped based on serum calcium and phosphorus levels, with those having hypercalcemia and hyperphosphatemia compared to those without. Diagnoses and procedures were identified using ICD-10 and CPT codes. Propensity score matching was applied to account for differences between groups. Post PCI outcomes were analyzed. Primary outcome was all-cause mortality. Secondary outcomes encompass coronary artery bypass grafting (CABG), myocardial infarction (MI), in-stent re-stenosis [redo PCI] and target vessel revascularization, heart failure (HF) exacerbations, and peri-/ post-procedural complications were assessed within a 5-year follow-up period. Kaplan-Meier analysis with log-rank was used for statistical comparisons, with significance set at p<0.05. Results The elevated CPP group was significantly associated with increased post-PCI all-cause mortality [hazard ratio (HR) 1.428], in-stent restenosis [HR 1.589], heart failure exacerbations [HR 1.492], and recurrent angina or MI [HR 1.396]. No significant differences were found in rates of post PCI CABG, periprocedural complications (postprocedural cardiac insufficiency, postprocedural cardiac arrest, postprocedural heart failure, intraoperative cerebrovascular infarction, postprocedural cerebrovascular infarction, and intraoperative cardiac arrest), or redo PCI. Conclusion In this propensity score-matched analysis, elevated CPP in CKD patients undergoing PCI was independently associated with worse outcomes, including higher mortality and cardiovascular event rates. These findings highlight the prognostic value of CPP and the need for closer metabolic monitoring and individualized risk stratification. Abstract Figure