Prognostic Significance of the Albumin Platelet Product for Mortality Risk in Pulmonary Embolism: A Retrospective...

BackgroundPulmonary embolism (PE) is a leading cause of cardiovascular mortality. The albumin platelet product (APP), a novel biomarker integrating nutritional and inflammatory status, is associated with adverse outcomes in various diseases. However, its prognostic value for mortality in patients with PE remains unclear.MethodsThis retrospective cohort study included 2355 patients with PE from the MIMIC-IV database. The primary exposure was APP, calculated as (albumin [g/dL]×platelet [K/µL]) / 100. The primary endpoints were all-cause mortality at 28 days, 90 days, and 365 days. The association between APP and mortality was assessed using restricted cubic splines (RCS), Kaplan-Meier survival curves, and multivariable Cox proportional hazards models. Subgroup analyses were performed to evaluate consistency across patient characteristics.ResultsUsing the tertile method, participants were stratified into three groups based on their APP levels (Tertile 1, Tertile 2, and Tertile 3), with Tertile1 designated as the reference group for comparative analyses against Tertile 2 and Tertile 3. RCS analysis revealed a statistically significant nonlinear relationship between APP levels and PE mortality (p for nonlinearity < 0.001). Kaplan-Meier survival analysis demonstrated a significantly higher risk of death among patients with lower APP levels (p < 0.01). Multivariable Cox proportional hazards regression models indicated an independent association between low APP levels and increased mortality risk at 28 days, 90 days, and 365 days, both before and after adjustment for potential confounders. Subgroup analyses showed no significant interaction between APP levels and mortality risk in most subgroups examined.ConclusionsIn patients diagnosed with PE, lower APP levels are significantly and independently associated with an increased risk of all-cause mortality. APP serves as a clinically useful predictor of long-term adverse outcomes in this population.