Development of the gut microbiota in healthy twins during the first 2 years of life and associations with body mass index z-score: Results from the Wuhan twin birth cohort study.

The gut microbiota undergoes rapid and vital changes to microbial community structure and the microbial-immune crosstalk during the first 3 years of life, which is thought to be involved in the pathobiology of later-life disease. Compared to single-born children, little is known about the gut microbiota of twins in early childhood. Based on the Wuhan Twin Birth Cohort study, 344 stool samples from 204 twin families were analyzed to investigate the difference in gut microbiota composition at 6, 12, and 24 months of age. Furthermore, this study evaluated the association between gut microbiota development curves and body mass index z-score (BMI_Z) curves at 6, 12, and 24 months of age. The predominant microbiota phyla identified in twins were Proteobacteria, Actinobacteriota, Firmicutes, Bacteroidota, and Verrucomicrobiota. The richness and diversity of gut microbiota increased from 6 to 24 months old (alpha diversity with p < 0.05). Beta diversity revealed 61 gut microbiota genera that were significantly different in relative abundance among the three age groups. Among the 61 gut microbiota genera, 30 distinct trajectory curves (DTCs) were generated by group-based trajectory models after log2 transformation of their relative abundance. Subsequently, Spearman correlation analysis revealed that only five gut microbiota DTC were correlated with the BMI_Z DTC. Therefore, we further examined the association between the five gut microbiota genera DTC and BMI_Z DTC using generalized estimation equation models. The results revealed a significant association between the DTC groups of Parabacteroides and that of BMI_Z (coefficient = 0.75, p = 0.04). The results of this study validated the hypothesis that the richness and diversity of gut microbiota developed with age in twins. Moreover, participants with a higher DTC of log2-transformed Parabacteroides had a higher BMI_Z DTC during the first 2 years of life. Further studies are needed to confirm the association between Parabacteroides and BMI_Z in other populations.

Gut Microbiota Diversity and Overweight/Obesity in Infancy: Results from a Nested Case-control Study.

OBJECTIVE: Childhood obesity is a major health concern worldwide. Previous studies have explored the relationship between obesity and gut microbiota. However, the results from such studies remain contradictory. METHODS: In the present nested case-control study, based on a twin birth cohort study, the relationship between gut microbiota diversity and overweight/obesity in 1- and 6-month-old infants was explored. Twins were enrolled when one child had normal weight and the other child was overweight/obese at six months old. For both infants, stool samples were collected at 1 and 6 months of age. Finally, 12 twins were enrolled in the study. The gut microbiota was identified by 16S rRNA gene sequencing in the V3-V4 area. Six of the twins were monozygotic. RESULTS: The results revealed that the microbiota communities of monozygotic twins were similar to those of dizygotic twins. The relative abundance (RA) of microbiota of 1-month-old twins was significantly higher than that of 6-month-old twins. However, the microbiota diversity of 1-month-old twins was significantly lower than that of 6-month-old twins. In addition, 6-month-old twins had significantly higher RA levels of Bifidobacterium and Lachnospiracea incertae sedis than 1-month-old twins. The 6-month-old group had significantly lower RA levels of Veillonella, Klebsiella, Akkermansia, Streptococcus, or Staphylococcus than the 1-month-old group. At six months, the RA level of Clostridium sensu stricto was higher in the overweight/obesity group than the normal-weight group. CONCLUSION: These findings imply that changes in gut microbiota diversity during infancy may contribute to the development of obesity in early infancy.

Risks of maternal prepregnancy overweight/obesity, excessive gestational weight gain, and bottle-feeding in infancy rapid weight gain: evidence from a cohort study in China.

Rapid weight gain (RWG) in infants is associated with numerous health problems, and its risk factors are still unclear. We assessed 98,097 maternal-infant pairs from a population-based cohort study and followed up with them until the infants were 6 months old. We assessed the associations between maternal prepregnancy weight status; gestational weight gain; feeding pattern; and infants' RWG at 0-1, 0-3, 1-3, and 3-6 months using multivariate unconditional logistic regression models, with controlled confounders. We found that maternal prepregnancy weight status, gestational weight gain, and feeding pattern at the 1st, 3rd, and 6th months had significant impacts on the infants' RWG at each time period (P<0.05). Infants with overweight/obese mothers had a higher risk of RWG after birth, whereas those of mothers who experienced excessive gestational weight gain had higher risks of RWG from birth than the other groups (P<0.01). Infants who were formula-fed had a higher risk of RWG than breastfed infants at the same time point (P<0.01). In conclusion, maternal prepregnancy obesity, excessive gestational weight gain, and formula-feeding were risk factors for infants' RWG during the first 6 months of life.

[Risk factors for otitis media with effusion in children].

OBJECTIVE: To identify the risk factors for otitis media with effusion (OME) in some kindergarten children in Wuhan City of China and analyze the results with reference to the review of the literature. METHODS: The study subjects were 3 to 6 years old children drawn from a school screening program for OME in Wuhan. All subjects were assessed with routine otorhinolaryngologic examination, otoscopic examination and tympanometry. During the test, parents were interviewed to provide information with regard to the children's birth history, neonatal history, feeding history, family smoke history, otological history, rhinorrhea, sneeze, nasal obstruction, snoring, tonsillitis episodes history, et al. These data formed the basis in the estimation of potential risk factors for OME. RESULTS: In the univariate analysis of 144 cases and 288 controls, significantly elevated odds ratios (OR) for OME were detected on the symptoms of nasal obstruction (OR = 2.60, P = 0.002), rhinorrhoea (OR = 1.442, P = 0.003), high hard palate (OR = 4.411, P < 0.0001), and previous history of acute otitis media (OR = 1.77, P = 0.025). However, four factors were found to be significant in the multivariate logistic regression model, including feeding history (OR = 0.746, P = 0.047), nasal obstruction (OR = 2.56, P = 0.003) and previous acute otitis media episodes (OR = 1.735, P = 0.032). CONCLUSIONS: Previous acute otitis media episodes and nasal obstruction were risk factors, which was accordant with literature. In addition, breastfeeding was a protective factor for OME, but acute tonsillitis was not a factor for OME. A child who had previous acute otitis media episode and often had nasal obstruction is suggested to have otorhinolaryngologic regulatory examination.