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 few contemporary studies stratify outcomes by specific CKD stages in the era of modern percutaneous coronary intervention (PCI) techniques and new-generation drug-eluting stents (DESs). We aim to assess the relationship between CKD and post-PCI outcomes in an updated, stage-specific, and long-term cohort. 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 after 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 in the 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.