External validation of CHIP score in patients undergoing in patients undergoing percutaneous coronary intervention in a large-scale Chinese cohort
Abstract Body (Do not enter title and authors here): Background: The CHIP score, developed from the BCIS (British Cardiovascular Intervention Society) database, predicts adverse in-hospital MACCE (major adverse cardiovascular and cerebrovascular events). However, its long-term prognostic value in Asian population remains unclear. This study aims to externally validate the CHIP score in a large Chinese cohort. Methods: We included 10,445 patients undergoing percutaneous coronary intervention (PCI), stratified into four groups based on the CHIP score (0, 1-2, 3-4, ≥5). The primary endpoint was 5-year MACCE, defined as a composite of all-cause mortality, myocardial infarction, and stroke. Secondary endpoints included the individual components of 5-year MACCE. Results: Higher CHIP scores were associated with significantly higher 5-year MACCE risk compared to a score of 0 (score 1-2: HR 1.31, 95% CI 1.15-1.49; score 3-4: HR 1.95, 95% CI 1.62-2.35; score ≥5: HR 3.81, 95% CI 2.93-4.96). This trend was consistent for 5-year all-cause mortality, myocardial infarction, and stroke. The discrimination ability of the CHIP score for 5-year MACCE risk was modest (C-statistics: 0.57, 95% CI: 0.55-0.59). For secondary endpoints, the discrimination for 5-year mortality risk was the highest (C-statistics: 0.61, 95% CI: 0.58-0.64). The Hosmer-Lemeshow goodness-of-fit test P values were all <0.05 for all endpoints. Conclusions: The CHIP score demonstrates a modest ability to predict 5-year MACCE and its individual components in a large Chinese cohort undergoing PCI. While it shows a clear trend of increasing risk with higher scores, further refinement and validation are needed to improve its predictive accuracy in this population.