Abstract
BACKGROUND: Older adults hospitalized with Community-Acquired Pneumonia (CAP) frequently experience early secondary cardiovascular events. The authors quantified risk factors and the incremental value of frailty and cardiac biomarkers beyond the Pneumonia Severity Index (PSI). METHODS: The authors ran a single-center, prospective cohort of adults ≥65-years with CAP admitted between January and December 2024. The primary endpoint was any in-hospital SCE (acute heart failure, MI/ACS per Fourth Universal Definition, new atrial fibrillation/flutter, ischemic stroke/TIA, or cardiovascular death). Prespecified predictors were prior cardiovascular disease, PSI, Clinical Frailty Scale (CFS), High-Sensitivity Troponin (hs-cTn), and NT-proBNP. Penalized multivariable logistic regression estimated adjusted odds ratios, 30- and 90-day outcomes were used to cause-specific Cox and Fine-Gray models. RESULTS: Among 172 patients (median age 77; 46% women), in-hospital SCEs occurred in 27.9% patients (48 out of 172 patients with 65 total component events; 95% CI 21.7-35.0), and 68.8% occurred within 72 h. Specifically, heart failure was 18.0%, new atrial fibrillation was 9.9%, MI was 5.8%, and cardiovascular death was 2.9%. In multivariable analysis, CFS ≥ 5 (Aor = 2.07, 95% CI 1.03-4.17), abnormal hs-cTn (aOR = 2.52, 1.25-5.06), and NT-proBNP per doubling (aOR = 1.38, 1.12-1.71) independently predicted SCEs. Discrimination improved from AUC 0.68 (PSI) to 0.73 with CFS and 0.79 with biomarkers (optimism-corrected 0.77), with NRI +0.18 and decision-curve net benefit at 10%-25% thresholds. Cumulative SCE incidence was 33.7% at 30-days and 37.8% at 90-days. Fine-Gray results were consistent. CONCLUSIONS: SCEs were common and occurred early after admission. Adding frailty and cardiac biomarkers to PSI improved risk stratification and may help high-risk patients receive closer monitoring. External validation is needed before its clinical application.