Association between Gut Microbiota and Infant's Temperament in the First Year of Life in a Chinese Birth Cohort

Abstract

Infant temperament characteristics play a critical role in children's developmental pathways and can predict adulthood psychopathology. The diversity and composition of the gut microbiota are associated with human temperament in both adults and young children. However, the relationship between the gut microbiota and temperament in 12-month-old infants is rarely studied; this developmental period is when temperament reaches a relatively stable stage. We used high-throughput sequencing methods to explore whether temperament characteristics were associated with gut microbiota diversity and composition. Infants' fecal samples were collected at 12 months of age for the gut microbiota analysis. Based on the primary caregivers' reports, infants' temperaments were measured using the Infant Behavior Questionnaire-revised (IBQ-R). This study included 51 infants, including 20 boys and 31 girls, with a mean age of 12.25 months. Results showed that soothability was positively correlated with maternal education level (β = 0.29, p = 0.043, adjust p = 0.025) and the abundance of Bifidobacterium genera (β = 0.62, p = 0.004, adjust p = 0.002). Conversely, cuddliness was negatively correlated with the abundance of Hungatella genera. There was no significant difference in temperament based on gender. This study demonstrated that gut microbiota composition was associated with temperament in 12-month-old infants. These results point to the importance of gut microbiota balance. Future studies on the mechanisms behind the gut microbiota affecting temperament are warranted.

Keywords: Chinese birth cohort; gut microbiota; infant; microbiota-gut-brain axis; temperament.

Figure 1

Distribution of microbial community for each sample at genus level. The data were visualized by Circos, and the width of the bars from each genus indicate the relative abundance of that genus in the sample.

Figure 2

Principal coordinate analysis (PCoA) of infant gut microbiota using Bray–Curtis distance matrix. A two-dimensional PCoA was used to describe the relative abundance of infant gut microbiota based on sex, delivery mode, feeding type, and probiotic consumption. Each point represents a single sample and is color-coded into different groups.

Figure 2

Principal coordinate analysis (PCoA) of infant gut microbiota using Bray–Curtis distance matrix. A two-dimensional PCoA was used to describe the relative abundance of infant gut microbiota based on sex, delivery mode, feeding type, and probiotic consumption. Each point represents a single sample and is color-coded into different groups.

Figure 2

Principal coordinate analysis (PCoA) of infant gut microbiota using Bray–Curtis distance matrix. A two-dimensional PCoA was used to describe the relative abundance of infant gut microbiota based on sex, delivery mode, feeding type, and probiotic consumption. Each point represents a single sample and is color-coded into different groups.

Figure 3

Relationships between bacterial composition and infants’ temperament. The figure shows a heatmap in which samples have been clustered according to their compositional profiles. Bacterial genera appear color-coded according to their under (green) or over-representation (red) in the samples (* 0.01 < p ≤ 0.05, ** 0.001 < p ≤ 0.01, *** p ≤ 0.001).