Gut microbiota and nutritional parameters differ in hemodialysis patients vs. healthy subjects
Protein energy wasting (PEW) is common in hemodialysis (HD) patients and associated with poor outcomes. This cross-sectional study compared gut microbiota and nutritional parameters of HD patients with and without PEW, chronic kidney disease (CKD) patients and healthy subjects.  HD patients with PEW (albumin <38g/l; dietary intakes <30 kcal/kg/d and <1g protein/kg/d) were matched forage and sex to HD patients without PEW, stage 4 CKD patients and healthy non-obese subjects. The primary endpointwas composition of gut microbiota. Secondary endpoints were body composition, resting energy expenditure, physicalfunction and activity, and systemic inflammation.  We included 33 patients and 11 healthy subjects. Composition of gut microbiota differed between healthysubjects and HD patients with (p=0.0005) or without PEW (p=0.03). DeSeq2 analysis identified decreased proportions of some propionate/butyrate-producing species (Dialister, Alistipes, Eubacterium) and increased levels of Streptococcus anginosus in HD patients. Compared to healthy subjects, HD patients with PEW had lower resting energy expenditure (p=0.032), mean steps per day (p=0.005), maximal handgrip strength (p=0.007) and higher plasma IL-6 levels (p=0.005). Maximal handgrip strength was lower in HD patients with PEW than in CKD patients (p=0.014).