Specific gut bacteria associated with lower risk of hospitalization for infections

Research presented on March 22, 2024 at European Congress of Clinical Microbiology and Infectious Diseases (ECCMID 2024) in Barcelona indicates that for every 10% increase in butyrate-producing bacteria in a patient’s gut, the risk of hospitalization for any infection falls by between 14 and 25%.

The authors said, “Microbiota alterations are common in patients hospitalized for severe infections and preclinical models have shown that anaerobic butyrate-producing gut bacteria protect against systemic infections. However, the relationship between microbiota disruptions and increased susceptibility to severe infections in humans remains unclear. We investigated the relationship between baseline gut microbiota and the risk of future infection-related hospitalization in two large population-based cohorts.”

The researchers investigated the correlation between baseline gut microbiota and the risk of future infection-related hospitalization, using data from two large population-based cohorts from the Netherlands ( HELIUS) and Finland (FINRISK 2002).

They characterized gut microbiota by sequencing the DNA of bacteria different types of bacteria in faecal samples of the subjects. They measured microbiota composition, diversity, and abundance of butyrate-producing bacteria.

The primary outcome of the study was hospitalization or death due to any infectious disease during 5–7-year follow-up after faecal sample collection.

The investigators evaluated gut microbiota from a total of 10,699 subjects from both national registries, Of these subjects, 602 were hospitalized or died due to infections (mainly community-acquired pneumonia) during followup.

They reported that gut microbiota composition of hospitalized or deceased subjects differed from those without hospitalization for infections.

Notably, they found that each 10% higher abundance of butyrate-producing bacteria was associated with a reduced risk of hospitalization for infections, 25% for subjects from the Dutch cohort and 14% lower for the Finnish cohort.

All infections were assessed together. The findings remained unchanged after adjustment for demographics, lifestyle, antibiotic exposure, and comorbidities.

The authors concluded, “Gut microbiome composition, specifically colonization with butyrate-producing bacteria, is associated with protection against hospitalisation for infectious diseases in the general population across two independent European cohorts. Further studies should investigate whether modulation of the microbiome can reduce the risk of severe infections.”