Gut microbiome composition is associated with long-term disability worsening in multiple sclerosis

Predicting the long-term outcome of multiple sclerosis (MS) remains an important challenge to this day. As the gut microbiota is emerging as a potential player in MS, we investigated in this study whether gut microbial composition at baseline is related to long-term disability worsening in a longitudinal cohort of 111 MS patients. Fecal samples and extensive host metadata were collected at baseline and 3 months post-baseline, with additional repeated neurological measurements performed over (median) 4.4 y. Worsening (with EDSS-Plus) occurred in 39/95 patients (outcome undetermined for 16 individuals). The inflammation-associated, dysbiotic Bacteroides 2 enterotype (Bact2) was detected at baseline in 43.6% of worsened patients, while only 16.1% of non-worsened patients harbored Bact2. This association was independent of identified confounders, and Bact2 was more strongly associated with EDSS-Plus than neurofilament light chain (NfL) plasma levels. Furthermore, using fecal sampling performed 3 months post-baseline, we observed Bact2 to be relatively stable, suggesting its potential use as a prognostic biomarker in MS clinical practice.

Automated summary

This study investigated the relationship between gut microbial composition and long-term disability worsening in 111 MS patients. The results showed that the inflammation-associated, dysbiotic Bacteroides 2 enterotype (Bact2) was more prevalent in patients with worsening disability compared to non-worsened patients. This association was independent of confounding factors and Bact2 showed a stronger association with disability worsening than neurofilament light chain (NfL) plasma levels. Additionally, Bact2 was relatively stable over time, suggesting its potential use as a prognostic biomarker in MS clinical practice.