Prognostic Implications of Chronic Kidney Disease Stage on Outcomes After Percutaneous Coronary Intervention

Aims: Chronic kidney disease (CKD) is associated with adverse cardiovascular outcomes, yet the prognostic impact of specific CKD stages following percutaneous coronary intervention (PCI) is not well defined. We assessed the relationship between CKD stage and clinical outcomes after PCI. Methods: We retrospectively analyzed 11,489 patients who underwent PCI between 2010 and 2020. Kidney function was classified as preserved (eGFR≥60 mL/min/1.73 m²), stage III CKD (eGFR 30–59), or stage IV/V CKD (eGFR<30) using the CKD-EPI equation. The primary endpoint was a composite of all-cause mortality, non-fatal myocardial infarction (MI), and target vessel revascularization (TVR) at 1 year; secondary endpoints included individual components and outcomes through 5 years. Associations were evaluated using multivariable Cox regression. Results: Stage III and stage IV/V CKD were present in 18% and 5.6% of patients, respectively. At 1 year, both stage III (HR 2.13, p<0.01) and stage IV/V CKD (HR 4.91, p<0.01) were associated with higher risk of the composite endpoint. Mortality rose sharply with CKD severity (33% in stage IV/V vs. 4% in preserved renal function), and MI risk was significantly higher in stage IV/V CKD. These associations persisted at 5 years. Unadjusted TVR risk was higher in stage IV/V CKD but lost significance after adjustment. Conclusions: CKD, particularly in advanced stages, is independently associated with increased mortality and MI after PCI, with effects persisting long-term. While advanced CKD showed higher unadjusted TVR risk, this was not independent after adjustment. These findings support individualized treatment strategies and extended follow-up in PCI patients with CKD.