Association of metabolic syndrome and prognosis in elderly patients with community-acquired pneumonia

Abstract

Background: This study aimed to evaluate the association between metabolic syndrome (MetS) and clinical outcomes in elderly patients hospitalized with community-acquired pneumonia (CAP). Methods: A retrospective cohort study was conducted on 712 elderly patients (aged ≥ 65 years) admitted with CAP to a tertiary hospital between 2018 and 2022. Patients were stratified into two groups based on MetS status (MetS group vs. non-MetS group). The primary outcome was 90-day all-cause mortality. Propensity score matching (PSM) was applied to balance baseline characteristics. Multivariate Cox regression and logistic regression analyses were performed to assess associations, adjusting for confounders. Results: After propensity score matching, 336 patients (168 MetS and 168 non-MetS) were included in the final analysis. The MetS group had a significantly higher 90-day mortality rate compared to the non-MetS group (29.8% vs. 11.9%, p < 0.01). Multivariate Cox regression analysis demonstrated that MetS was independently associated with a 1.98-fold increased risk of mortality (95% CI: 1.08–3.63; p = 0.03). A clear dose-response relationship was observed, with each additional MetS component increasing mortality risk by 1.46-fold (95% CI: 1.11–2.16; p < 0.01). Conclusion: MetS is an independent predictor of worse short-term outcomes in elderly CAP patients, including higher mortality and longer hospital stays. Early recognition and management of MetS may improve prognosis in this high-risk population.