Abstract
OBJECTIVES: The purpose of this study was to verify whether guideline-directed medical therapy (GDMT, ie, the combined use of β-blocker, ACE inhibitor/angiotensin receptor blocker, dual antiplatelet drugs and statin) could improve in-hospital mortality in acute coronary syndrome (ACS) patients with advanced renal dysfunction (estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m(2)). DESIGN: Retrospective cohort study. SETTING: This study used data from two large, multicentre, observational cohorts: the Chinese National Electronic Disease Surveillance System Platform (CNEDSSP) and the Improving Care for Cardiovascular Disease in China-ACS (CCC-ACS) project. These cohorts consist of ACS patients admitted to 47 and 241 hospitals, respectively, across China from 2014 to 2019. PARTICIPANTS: A total of 6260 patients diagnosed with advanced renal dysfunction (eGFR <30 mL/min/1.73 m²) on admission were included in the analysis. Among these, 3013 patients were from the CNEDSSP cohort and 3247 from the CCC-ACS cohort. Patients were categorised based on receipt of GDMT within 24 hours of admission. MAIN EXPOSURE MEASURE: The main exposure measure was the early use of GDMT, defined as the administration of all four components of GDMT within 24 hours of hospital admission. MAIN OUTCOME MEASURE: The primary outcome was in-hospital mortality, assessed within the study cohort. RESULTS: In a pooled analysis of the CNEDSSP and CCC-ACS cohorts, early GDMT was associated with a significant reduction in in-hospital mortality (relative risk (RR): 0.62, 95% CI: 0.47 to 0.81). More pronounced reductions were observed in myocardial infarction (MI) patients, with HRs of 0.31 (95% CI: 0.17 to 0.55) in the CNEDSSP cohort and 0.47 (95% CI: 0.28 to 0.77) in the CCC-ACS cohort. A random-effects pooled analysis of MI patients with advanced renal dysfunction at admission showed a 61% reduction in in-hospital mortality among GDMT users (RR: 0.39, 95% CI: 0.27 to 0.58). CONCLUSIONS: This nationwide study highlights that early GDMT is associated with a reduced risk of in-hospital mortality in ACS patients (particularly in MI patients) with advanced renal dysfunction.