ESPE Abstracts

Background: While differences in gut microbiota between obese and lean subjects have been described, few studies have examined how adiposity across childhood relates to intestinal microbiota composition and diversity in late adolescence.

Objective: To explore the correlations between measures of adiposity from childhood and adolescence with intestinal microbiota composition and diversity at 15–17 years.

Methods: Data stem from the QUALITY cohort, a cohort study of 630 children with a parental history of obesity. Adiposity was assessed at 8–10 years, 10–12 years and 15–17 years. Height, weight and waist circumference were measured using standardized protocols, and body mass index z-scores (zBMI) were calculated and participants were classified into weight categories according to CDC reference standards. Percent fat mass was assessed using DXA. 16S-rRNA based microbial profiling of stool samples obtained from 22 participants at 15–17 years were conducted to determine the composition and diversity of microbiota. Alpha-diversity indices used to assess richness include observed OTUs and the Chao1 index, whereas the Shannon and Simpson indices measured richness and evenness. Pearson’s correlations assessed associations between diversity indices and measures of adiposity.

Results: Of the 22 participants, 14 were normal weight, six were overweight and two were obese. zBMI across all ages was negatively correlated with the Shannon and Simpson indices. In particular, the correlation of zBMI at 15–17 years with the Simpson index was −0.41 (P=0.057). Similar, albeit weaker, negative correlations were noted with measures of evenness and percent fat mass, however none reached statistical significance. Waist circumference was also negatively associated with the Shannon and Simpson indices, with the strongest correlations being with waist circumference at 10–12 and 15–17 years and the Simpson index (r=−0.42, P=0.067 and −0.40, P=0.065 respectively). In contrast, measures of adiposity across all ages were positively correlated with measures of richness. The strongest correlations were between zBMI at 15–17 years (r=0.50, P=0.019) and waist circumference at 15–17 years (r=0.39, P=0.075) and the Chao-1 index. At the genus level, we found a significantly greater abundance of Roseburia in the overweight/obese group compared to normal weight youth.

Conclusions: These preliminary data in a small sample of children suggest that increased adiposity in early life is associated with differences in gut microbiota diversity indices in late adolescence. The greater abundance of Roseburia, a butyrate producing bacteria, in the gut microbiota of the overweight/obese group remains to be confirmed in a larger sample size.