Pneumonia is a leading cause of morbidity and mortality in elderly populations, yet conventional risk stratification tools such as the Pneumonia Severity Index (PSI) and CURB- 65 often underestimate mortality risk in this group. Inflammatory biomarkers, including C- reactive protein (CRP) and procalcitonin (PCT), have shown inconsistent prognostic performance in older adults. Soluble urokinase plasminogen activator receptor (suPAR) is a novel biomarker reflecting systemic immune activation and physiological vulnerability, with stable plasma levels and practical feasibility for clinical use.

This thesis evaluates the additive prognostic value of suPAR for 30-day mortality in elderly patients with suspected community-acquired pneumonia. Using the computational toolbox PanelomiX, we developed a multimodal prognostic panel combining suPAR, Pneumonia Severity Index (PSI), and Body Mass Index (BMI) to integrate inflammatory, clinical, and nutritional dimensions. The model achieved 100% sensitivity and 64.9% specificity, outperforming established scores and individual biomarkers.

Our findings demonstrate that suPAR, when combined with PSI and BMI, provides robust mortality risk stratification by capturing both biological stress and physiological reserve. This approach supports early identification of high-risk elderly patients, informs triage decisions, and facilitates individualized management. Multimodal prognostic panels integrating suPAR offer a clinically feasible strategy to enhance precision geriatrics and optimize outcomes in older adults presenting with pneumonia.

These findings are preliminary and require prospective validation in larger, multicenter cohorts before clinical implementation.