Gut microbiota composition and derived enterotypes are associated with ponderal status in preschool children. Childhood obesity risk assessment longitudinal study (CORALS) cohort.

Alpha diversity decreased with increasing BMI in preschool children, particularly in obesity.

• Study included 1134 children aged 3-6 years from the CORALS cohort.
• Shannon diversity index showed significant decrease with increasing BMI (adj.P = 0.00301).
• Simpson diversity index also showed significant decrease with increasing BMI (adj.P = 0.00158).
• Participants were stratified by weight status into underweight, normal weight, overweight, and obesity groups.
• Shotgun metagenomic sequencing of stool samples was used for microbiota analysis.

Beta diversity revealed distinct microbial community structures across weight status groups.

• Beta diversity analysis showed statistically significant differences in microbial structure across weight groups (p = 0.001).
• Analysis was performed using shotgun metagenomic sequencing in 1134 preschool children.
• Analyses were conducted in R and assessed alpha/beta diversity, taxonomic composition, enterotypes, and microbial pathways.

Four distinct enterotypes were identified, with obesity associated with Enterotype 3 (Segatella-dominated) and underweight/normal weight associated with Enterotype 1.

• Obesity was significantly associated with Enterotype 3, which was dominated by Segatella (p = 0.023).
• Enterotype 1, characterized by Alistipes, Akkermansia, and Coprococcus, was enriched in underweight and normal weight children.
• Four enterotypes in total were identified from the cohort of 1134 children aged 3-6 years.

Specific microbial species were differentially abundant in obesity compared to other weight status groups.

• Phocaeicola dorei was found at higher levels in obesity (adj.P = 0.003).
• Segatella hominis was found at higher levels in obesity (adj.P = 0.001).
• Longicatena caecimuris was found at lower levels in obesity (adj.P = 0.03).
• Blautia parvula was found at lower levels in obesity (adj.P = 0.003).

Functional analyses revealed downregulation of vitamin and nucleotide biosynthesis pathways and reduced carbohydrate metabolism in overweight and obese children.

• Vitamin biosynthesis pathways were downregulated in overweight/obesity groups.
• Nucleotide biosynthesis pathways were downregulated in overweight/obesity groups.
• Carbohydrate metabolism was reduced in overweight/obesity groups.
• Functional pathway analysis was performed as part of shotgun metagenomic sequencing analyses in R.

The CORALS cohort is a childhood obesity risk assessment longitudinal study registered with a clinical trial identifier.

• The study enrolled 1134 children aged 3-6 years.
• The baseline analysis used a cross-sectional design.
• The cohort is registered under ClinicalTrials.gov ID NCT06317883.
• Participants were stratified by weight status into underweight, normal weight, overweight, and obesity categories.