Prognostic value of the C-reactive protein–albumin–lymphocyte index for predicting one-year mortality in acute pulmonary embolism

Abstract

Acute pulmonary embolism (APE) is associated with substantial mortality despite advances in diagnosis and treatment. Biomarkers reflecting inflammation, immune status, and nutritional reserve may improve risk stratification. This study aimed to evaluate the prognostic significance of the C-reactive protein–albumin–lymphocyte (CALLY) index for predicting one-year mortality in patients with APE and to compare its performance with the Prognostic Nutritional Index (PNI) and Systemic Immune-Inflammation Index (SII). This retrospective single-center study included 471 consecutive patients diagnosed with APE between July 2021 and December 2024. The primary endpoint was one-year all-cause mortality. CALLY, PNI, and SII were calculated using admission laboratory parameters. Receiver operating characteristic (ROC) analysis and Cox regression models were performed to evaluate the prognostic performance of these indices. During one-year follow-up, 102 patients (21.7%) died. CALLY values were significantly lower in non-survivors than in survivors ( p  < 0.001). CALLY demonstrated the highest discriminatory performance for one-year mortality (AUC 0.787, 95% CI 0.732–0.842), compared with PNI (AUC 0.728) and SII (AUC 0.643). CALLY remained independently associated with one-year mortality after multivariable adjustment (HR 0.904, 95% CI 0.856–0.955; p  < 0.001). Furthermore, adding CALLY to a baseline model including age, sPESI ≥1, elevated cardiac troponin, and sPAP increased the C-statistic from 0.700 to 0.739 and significantly improved model fit (likelihood-ratio p  < 0.001). The CALLY index was independently associated with one-year all-cause mortality in patients with APE and demonstrated higher discriminatory performance than PNI and SII. As a simple index derived from routinely available laboratory parameters, CALLY may provide additional prognostic information for long-term risk assessment in APE.