Microbial composition and psychological wellbeing

The gut-brain axis was revisited from an interesting angle: Dr Luc Biedermann (University Hospital Zurich, Switzerland) and colleagues looked at a potential interplay between microbial composition and validated psychological outcome measurements in inflammatory bowel disease (IBD) patients [1]. They found significant alterations in the intestinal mucosa-associated microbiome composition in IBD patients in remission in relation to psychological wellbeing and quality of life.

Study participants were 171 patients with available microbial sampling who were in clinical remission, to exclude a potential impact of disease activity. Patients with higher perceived stress had significantly lower alpha diversity, whereas patients with high vs low levels of anxiety and depressive symptoms showed no substantial differences in alpha diversity. In IBD patients with vs without depression or anxiety, beta diversity was significantly different (as shown in the Figure). Looking at specific operational taxonomic unit (OTUs), several significant alterations across groups were seen. These included significant increases in represents of Proteobacteria, such as Desulfovibrio (P=0.001), in ulcerative colitis patients, as well as decreases in numerous genus of Firmicutes, such as Lachnospiraceae (P<0.001), in Crohn’s disease and ulcerative colitis patients with depression; and decreases in Lactobacillales (Streptopcoccaceae) in Crohn’s disease patients with anxiety (P<0.001).

Figure: Beta diversity in IBD patients with vs without depression or anxiety [1]



Principal component analysis of microbial beta diversity according to severity (subgroup 1 = moderately increased, subgroup 2 = severe vs normal anxiety and depression) of psychological alteration (no ulcerative colitis patients with severe depression in this sample). CD, Crohn’s disease; UC, ulcerative colitis.

Dr Biedermann noted that further studies are warranted to gain more insight into the direction of the link between microbial composition and psychological wellbeing, and to investigate whether intestinal inflammation subsequent to microbial alterations or microbial metabolites itself may impair psychological wellbeing.

1. Humbel F, et al. ECCO 2019, OP06.

Posted on 9 May 201917 May 2024