A nonlinear association between platelet-to-albumin ratio and one-year all-cause mortality in acute coronary syndrome patients

Background The platelet-to-albumin ratio (PAR) has shown to be linked with cardiovascular disorders. However, the specific association between the admission PAR and one-year outcomes in patients with acute coronary syndrome (ACS) remains to be fully characterized. This study investigated the linkage between PAR levels and the occurrence of one-year all-cause mortality and major adverse cardiovascular and cerebrovascular events (MACCEs) in the ACS population.Patients and methods This retrospective cohort study enrolled patients diagnosed with ACS between January 2022 and December 2023. The primary endpoint was one-year all-cause mortality, and the secondary endpoint was MACCE, defined as a composite of all-cause mortality, non-fatal myocardial infarction, ischemic stroke, heart failure rehospitalization, target vessel revascularization or in-stent thrombosis, and malignant arrhythmia. To evaluate the relationship between PAR and these clinical events, we employed multivariate Cox proportional hazards models, restricted cubic splines (RCSs) and two-piecewise linear regression to identify potential non-linear associations and specific inflection points.Results A total of 1326 participants (median age: 67 years) were followed for one year, during which 137 (10.3%) deaths and 280 (21.1%) MACCE events occurred. The one-year all-cause mortality rates across the PAR quartiles (Q1–Q4) were 11.6%, 6.1%, 7.0% and 16.7%, respectively, with a similar trend observed for MACCE (22.1%, 15.2%, 18.7% and 28.5%). RCS analysis revealed significant nonlinear associations between the PAR and both clinical endpoints (all p for nonlinear < 0.05). Two-piecewise linear regression analysis identified specific inflection points at 5.28 (95% confidence interval [CI]: 4.86–9.86) for one-year all-cause mortality and 5.29 (95% CI: 4.37–6.58) for MACCE.Conclusions The PAR demonstrates a significant nonlinear relationship with one-year all-cause mortality and MACCE in patients with ACS.