Association between gut microbiota and obesity combined with high carotid intima-media thickness among Chinese children.

Background and objectives: Obesity and related target organ damage such as high carotid intima-media thickness (cIMT) in children is associated with cardiovascular disease (CVD) later in life. However, the asso-ciation between gut microbiota and obesity combined with high cIMT among children remains unclear. Therefore, we compared differences in composition, community diversity, and richness of gut microbiota among normal children and obesity combined with or without high cIMT to identify differential microbiota biomarkers.

Methods and study design: A total of 24 children with obesity combined with high cIMT (OB+high-cIMT), 24 with obesity but normal cIMT (OB+non-high cIMT), and 24 with normal weight and normal cIMT aged 10-11 years matched by age and sex from the "Huantai Childhood Cardiovascular Health Cohort Study" were included. All included fecal samples were tested using 16S rRNA gene sequencing.

Results: The community richness and diversity of gut microbiota in OB+high-cIMT children were decreased compared with OB+non-high cIMT children and normal children. At the genus level, the relative abundances of Christensenellaceae_R-7_group, UBA1819, Family_XIII_AD3011_group, and unclassi-fied_o_Bacteroidales were associated with reduced odds of OB+high-cIMT among children. Receiver operating characteristic (ROC) analysis showed that combined Christensenellaceae_R-7_group, UBA1819, Fami-ly_XIII_AD3011_group, and unclassified_o_Bacteroidales performed a high ability in identifying OB+high-cIMT. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) showed that several pathways such as biosynthesis of amino acids and aminoacyl-tRNA pathways were lower in the OB+high-cIMT group compared with the normal group.

Conclusions: We found that the alteration of gut microbiota was associated with OB+high-cIMT among children, which indicates that the gut microbiota may be a marker for obesity and related cardiovascular damage among children.