Assessment of a novel functional food modulating the microbiota-inflammation-brain axis in patients with heart failure and/or /atrial fibrillation patients (the AMBROSIA study): Protocol for a randomized controlled trial.

BACKGROUND AND AIMS: Atrial fibrillation (AF), heart failure (HF), and undernutrition represent a complex triad with major clinical and socioeconomic consequences in older adults, often predisposing to frailty. Undernutrition often remains underdiagnosed due to a reliance on weight-based measures and limited awareness of inflammation-related cachexia. The AMBROSIA study aims to fill these gaps by exploring the response of the microbiota-inflammation-brain axis to a targeted, fortified food product-based intervention, with comprehensive outcome assessments, alongside mechanistic/exploratory -omics analyses and gut microbiota (GM) functional profiling.

METHODS AND

RESULTS

This single-center, prospective, parallel-group randomized controlled trial aims to enroll 120 older adults with confirmed AF and/or HF. Participants will be randomized 1:1 into an intervention group (n = 60) or control group (n = 60). All participants receive individualized dietary counseling; the intervention group additionally consumes one AMBROSIA nutritional bar daily for six months. The bar contains hydrolyzed proteins, inulin, CoQ₁₀, and probiotics (L. rhamnosus IMC 501® and L. paracasei IMC 502®) in a flavonoid-rich chocolate matrix. Clinical, cognitive, and nutritional data, along with blood, saliva, urine, and stool samples, will be collected at baseline, 3, and 6 months. The primary endpoint is the change in skeletal muscle mass, physical function and frailty, while secondary endpoints include changes in nutritional status, inflammation, GM, metabolomics, and quality of life.

CONCLUSION

By integrating cutting-edge omics tools and a multidimensional nutritional strategy, AMBROSIA aims to uncover mechanisms driving undernutrition and identify biomarkers to support personalized interventions for older patients with AF and HF.