Long-term follow-up study on the impact of a gut microbiota-supportive diet on heart failure and mortality outcomes

Diet-driven modulation of gut microbiota may influence heart failure (HF) risk and mortality, but evidence in large populations is limited. We evaluated the association between a Dietary Index for Gut Microbiota (DI-GM) and prevalent HF.

DI-GM scores were derived from two 24-h dietary recalls. Logistic regression assessed odds of HF, diabetes, stroke, kidney failure, hypertension, and rheumatoid arthritis across DI-GM categories (1-3, 4, 5, ≥6), adjusting for demographics, lifestyle, BMI, and comorbidities. Restricted cubic splines examined dose-response. Mediation analysis quantified the roles of systemic immune-inflammation index (SII) and C-reactive protein (CRP). Kaplan-Meier and Cox models evaluated all-cause and cardiovascular mortality by DI-GM (>4 vs 1-4).

Compared to DI-GM 1-3, scores of 5 and ≥6 were associated with 21-40 % lower odds of HF (adjusted OR 0.79, p = 0.034; OR 0.60, p = 2.3 × 10^-5). Similar inverse associations were observed for diabetes, stroke, and kidney failure. Spline analysis revealed a nonlinear HF risk decline beyond scores of 4-5. Component-level analyses showed fiber and coffee were linked to significant reductions in CRP, SII and heart failure odds (fiber OR 0.85; coffee OR 0.77). Mediation by SII and CRP accounted for 26 % and 32 % of the DI-GM-HF association. Higher DI-GM (>4) predicted lower all-cause (HR 0.83; p < 0.001) and cardiovascular mortality (HR 0.71; p < 0.001).

Gut-microbiota-supportive diet (DI-GM ≥ 5) is linked to substantially lower prevalence of HF and related conditions, partly via reduced inflammation, and confers long-term survival benefits.