Mitigating Diarrhoea-Related Inflammation in Frail Older Adults with Postbiotic-Enhanced ORS: Insights from a Pilot Study

Background: /Objectives: Diarrhoea in older adults can lead to dehydration and malnutrition, impair gut barrier function, and impact overall health and quality of life. This pilot study evaluated the effects of a new oral rehydration solution (ORS) with the postbiotic ABB C22® on diarrhoea and associated inflammation in an elderly population. Methods: Forty-seven participants with diarrhoea were randomized to receive treatment with either ORS enriched with ABB C22®, or standard treatment of ORS with placebo. Participants were treated for a maximum of 14 days across two hospital centres in Barcelona, Spain. The primary endpoints of the study were the reduction in faecal levels of the inflammatory biomarkers calprotectin, lactoferrin and immunoglobulin A. Secondary endpoints included changes in stool consistency and tolerability. Results: At day 14, the ORS + ABB C22® group showed greater reductions from baseline in faecal calprotectin and lactoferrin levels compared with the ORS + placebo group, with lactoferrin-positive cases being halved by day 3. Stool consistency according to the Bristol stool scale improved in both groups. No adverse events were reported in either group. Conclusions: This study highlights that inflammation associated with diarrhoea is often overlooked. While standard ORS improves stool consistency and hydration parameters, it does not address the underlying inflammation in a largely frail population. ABB C22® postbiotic-enriched ORS showed superior anti-inflammatory effects compared with ORS + placebo. These results suggest that postbiotics may offer a novel approach to treating both the symptoms and inflammation associated with diarrhoea. Further research is needed to confirm the clinical benefits of postbiotic-enriched ORS formulations in larger patient populations, and to assess their effect on other digestive diseases.