Excessive alcohol intake can alter the gut microbiota, which may underlie the
pathophysiology of alcohol-related diseases. We examined gut microbiota composition
and functions in patients with alcohol overconsumption for >10 years, compared to a
control group of patients with a history of no or low alcohol intake. Faecal microbiota
composition was assessed by 16S rRNA sequencing. Gut microbiota functions were
evaluated by quantification of short-chain fatty acids (SCFAs) and predictive
metagenome profiling (PICRUSt). Twenty-four patients, mean age 64.8 years (19
males), with alcohol overconsumption, and eighteen control patients, mean age 58.2
years (14 males) were included. The two groups were comparable regarding basic
clinical variables. Nutritional assessment revealed lower total score on the screening
tool Mini Nutritional Assessment, lower muscle mass as assessed by handgrip
strength, and lower plasma vitamin C levels in the alcohol overconsumption group.
Bacteria from phylum Proteobacteria were found in higher relative abundance, while
bacteria from genus Faecalibacterium were found in lower relative abundance in the
group of alcohol overconsumers. The group also had higher levels of the genera
Sutterella, Holdemania and Clostridium, and lower concentration and percentage of
butyric acid. When applying PICRUSt to predict the metagenomic composition, we
found that genes related to invasion of epithelial cells were more common in the group
of alcohol overconsumers. We conclude that gut microbiota composition and functions
in patients with alcohol overconsumption differ from patients with low consumption of
alcohol, and seem to be skewed into a putative pro-inflammatory direction. Less...