Gut Microbiome Is Related to Cognitive Impairment in Peritoneal Dialysis Patients

Gut microbiota disturbances may influence cognitive function, increasing uremic toxins and inflammation in dialysis patients; therefore, we aimed to evaluate the association of the gut microbiota profile with cognitive impairment (CI) in patients on automated peritoneal dialysis (APD). In a cross-sectional study, cognitive function was evaluated using the Montreal Cognitive Assessment in 39 APD patients and classified as normal cognitive function and CI. The gut microbiota was analyzed using the 16S rRNA gene sequencing approach. All patients had clinical, biochemical and urea clearance evaluations. Eighty-two percent of patients were men, with a mean age of 47 ± 24 years and 11 (7-48) months on PD therapy; 64% had mild CI. Patients with CI were older (53 ± 16 vs. 38 ± 14, <i>p</i> = 0.006) and had a higher frequency of diabetes mellitus (56% vs. 21%, <i>p</i> = 0.04) and constipation (7% vs. 48%, <i>p</i> = 0.04) and lower creatinine concentrations (11.3 ± 3.7 vs. 14.9 ± 5.4, <i>p</i> = 0.02) compared to normal cognitive function patients. Patients with CI showed a preponderance of S24_7, Rikenellaceae, Odoribacteraceae, <i>Odoribacter</i> and <i>Anaerotruncus</i>, while patients without CI had a greater abundance of <i>Dorea</i>, <i>Ruminococcus</i>, <i>Sutterella</i> and <i>Fusobacteria</i> (LDA score (Log₁₀) > 2.5; <i>p</i> < 0.05). After glucose and age adjustment, Odoribacter was still associated with CI. In conclusion, patients with CI had a different gut microbiota characterized by the higher abundance of indole-producing and mucin-fermenting bacteria compared to normal cognitive function patients.