Abstract P198: Association Between Oral Microbiome, Inflammation, Endotoxemia, And Heart Failure Severity

Introduction: Gut microbial imbalance may contribute to endotoxemia, inflammation and oxidative stress in heart failure (HF). Changes occurring in the oral microbiota and inflammatory/oxidative milieu during HF progression are unknown. Hypothesis: The oral microbiome will be associated with HF severity New York Heart Association, Class I/II, III, IV. Methods: We enrolled 167 patients with HF with reduced ejection fraction (mean age 59±14, 85% Male, 47% White, mean LVEF 20±9, 49% smokers). Biomarkers of endotoxemia (LPS, sCD14) and inflammation (CRP, IL6, TNF-α) were measured in 150 blood samples. A total of 167 oral samples were analyzed using 16S rRNA sequencing. Alpha diversity was assessed via Shannon Index and regressed on HF severity and biomarker levels with linear models. The association between HF severity and Beta diversity (Bray-Curtis dissimilarity) was assessed with PERMANOVA. DESeq2 regressed taxa abundance on HF severity and below vs. above median biomarker levels; multiple comparisons were controlled with the false discovery rate. Models were adjusted for age, sex, race/ethnicity, and smoking status. Results: Mean Shannon Index values±SD across HF class I/II (N=50), III (N=65), and IV (N=52) were 3.28±0.47, 3.42±0.49, 3.20±0.78. NYHA class was associated with both Alpha (p<.01) and Beta diversity (p<.05). Decreased Alpha diversity was associated with ischemic etiology (p<.05), but not with sex, smoking, age, race/ethnicity, or clinical variables, including antibiotic use. In unadjusted models, increased Alpha Diversity was associated with decreased inflammation: IL6 (r=-0.16), TNF-α (r=-0.18), CRP (r=-0.21); all p<.05. Statistical significance was lost after adjustment. Several taxa differed by NYHA class, levels of inflammation, and endotoxemia in multivariable models ( Figure ). Conclusions: HF severity, inflammation, and endotoxemia were associated with oral microbial diversity and bacteria linked to poor oral health, including Treponema denticola and Porphyromonas gingivalis .