Advanced oxidation protein products and ischemia-modified albumin as prognostic biomarkers of long-term mortality in community-acquired pneumonia: a prospective observational study

Oxidative stress is increasingly recognized as a contributor to the pathophysiology and outcomes of community-acquired pneumonia (CAP). This study examined whether plasma levels of advanced oxidation protein products (AOPPs) and ischemia-modified albumin (IMA) measured at hospital admission are associated with 100-day mortality. A cohort of 71 hospitalized CAP patients was analyzed. Plasma AOPPs and IMA were measured within 24 h of admission and evaluated in relation to clinical data, the Charlson Comorbidity Index (CCI), and routine laboratory parameters. Statistical analyses included receiver operating characteristic (ROC) curve evaluation, Kaplan–Meier survival estimates, and Spearman correlations. AOPPs correlated positively with D-dimer, while IMA showed positive associations with N-terminal pro–B-type natriuretic peptide and high-sensitivity cardiac troponin I, and inversely with serum albumin, indicating links between oxidative stress, inflammation, and cardiovascular dysfunction. Higher admission levels of AOPPs and IMA were independently associated with increased 100-day mortality. In ROC analysis, AOPPs demonstrated good discriminatory ability for 100-day mortality (area under the curve [AUC] = 0.75, p < 0.0001), and a combined multivariable model including AOPPs, IMA, and CCI further improved performance (AUC = 0.851, p < 0.0001). These findings suggest that oxidative stress biomarkers measured at admission may serve as accessible indicators of long-term mortality risk in CAP.