Background: Community-acquired pneumonia (CAP) leads to high morbidity and mortality among the elderly, with 3 million deaths annually worldwide. Multiple comorbidities significantly increase the risk. This study aims to identify independent risk factors for mortality in elderly patients with CAP to optimize individualized treatment strategies.Methods: This single-center retrospective study was conducted at First Affiliated Hospital of Xi’an Medical University. Clinical data from elderly patients diagnosed with CAP between December 2018 and December 2023 were retrospectively collected. Logistic regression analysis was used to determine risk factors for in-hospital mortality. A nomogram was constructed based on the final model for risk assessment.Results: A total of 613 eligible patients were included, with 68.2% being male, and a median age of 78 (IQR 70–86) years. The prevalence of hypertension, coronary heart disease (CHD), stroke, diabetes, malignancy, and chronic obstructive pulmonary disease (COPD) was 55.5, 39.8, 29.5, 27, 16.6, and 7%, respectively. The in-hospital mortality rate was 48%. Compared to survivors, non-survivors were older, had a higher proportion of males, faster heart rates, and higher rates of comorbidities. Multivariate logistic regression analysis identified age (OR 1.05, 95% CI [1.02–1.07], P < 0.01), BMI (OR 0.92, 95% CI [0.86–0.98], P < 0.01), stroke (OR 2.21, 95% [1.43–3.42], P < 0.01), ARDS (OR 4.0, 95% CI [2.17–7.37], P < 0.01), AKI (OR 2.98, 95% CI [1.77–5.01], P < 0.01), malignancy (OR 2.11, 95% CI [1.22–3.65], P < 0.01), elevated WBC (OR 1.20, 95% [1.14–1.27], P < 0.01), PLT (OR 0.995, 95% CI [0.993–0.998], P < 0.01), and albumin (OR 0.93, 95% CI [0.90–0.97], P < 0.01) as independent risk factors for in-hospital mortality. The area under the curve (AUC) of the multivariable model was 0.85 (95% CI [0.81–0.87], P < 0.01).Conclusion: Elderly CAP patients have a high prevalence of comorbidities and a high in-hospital mortality rate. Advanced age, low BMI, stroke, ARDS, AKI, malignancy, elevated WBC, decreased PLT, and low albumin were independent risk factors for in-hospital mortality.

Background: Heart failure (HF) is a primary cause of death in patients on maintenance hemodialysis (MHD), yet the role of microbial dysbiosis is poorly defined. This study characterized the salivary and gut microbiomes of MHD patients with heart failure with preserved ejection fraction (HFpEF), those without HF (NHF), and healthy controls (CON). Methods: In this cross-sectional study (n=88), we compared the salivary and fecal microbiomes of HFpEF (n=30), NHF (n=30), and CON (n=28) groups using 16S rRNA gene sequencing. Microbial community structure and composition were analyzed. Results: Alpha diversity and Beta diversity analysis revealed a distinct salivary microbial structure, which effectively distinguished the MHD group from the Con group (P < 0.05). Conversely, the overall gut community structure showed no significant separation. At the genus level, both MHD groups showed depletion of salivary Veillonella and gut Faecalibacterium compared to controls. Notably, LEfSe analysis highlighted salivary Anaerocolumna as a promising candidate feature associated with the HFpEF group. Conclusion: Our analyses suggest that HFpEF in MHD patients may be associated with structural alterations in the oral microbiome, which appear more pronounced than those in the gut. Specific oral microbial signatures, particularly the enrichment of Anaerocolumna, showed associations with the HFpEF cohort in our study. This preliminary evidence positions the oral microbiome as an area worthy of further investigation for its potential role in this high-risk population.