title: Gut microbiome composition is associated with temperament during early childhood.
abstract: BACKGROUND
  Understanding the dynamics of the gut-brain axis has clinical implications for physical and mental health conditions, including obesity and anxiety. As such disorders have early life antecedents, it is of value to determine if associations between the gut microbiome and behavior are present in early life in humans.
  
  
  METHODS
  We used next generation pyrosequencing to examine associations between the community structure of the gut microbiome and maternal ratings of child temperament in 77 children at 18-27months of age. It was hypothesized that children would differ in their gut microbial structure, as indicated by measures of alpha and beta diversity, based on their temperamental characteristics.
  
  
  RESULTS
  Among both boys and girls, greater Surgency/Extraversion was associated greater phylogenetic diversity. In addition, among boys only, subscales loading on this composite scale were associated with differences in phylogenetic diversity, the Shannon Diversity index (SDI), beta diversity, and differences in abundances of Dialister, Rikenellaceae, Ruminococcaceae, and Parabacteroides. In girls only, higher Effortful Control was associated with a lower SDI score and differences in both beta diversity and Rikenellaceae were observed in relation to Fear. Some differences in dietary patterns were observed in relation to temperament, but these did not account for the observed differences in the microbiome.
  
  
  CONCLUSIONS
  Differences in gut microbiome composition, including alpha diversity, beta diversity, and abundances of specific bacterial species, were observed in association with temperament in toddlers. This study was cross-sectional and observational and, therefore, does not permit determination of the causal direction of effects. However, if bidirectional brain-gut relationships are present in humans in early life, this may represent an opportunity for intervention relevant to physical as well as mental health disorders.
authors.affiliation: Department of Psychiatry, The Ohio State University Wexner Medical Center, United States; The Institute for Behavioral Medicine Research, The Ohio State University Wexner Medical Center, United States; Department of Obstetrics and Gynecology, The Ohio State University Wexner Medical Center, United States; Department of Psychology, The Ohio State University, United States. Electronic address: Lisa.Christian@osumc.edu.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Christian
authors.affiliation: The Institute for Behavioral Medicine Research, The Ohio State University Wexner Medical Center, United States; Division of Biosciences, The Ohio State University, United States.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Galley
authors.affiliation: Center for Biostatistics, College of Medicine, The Ohio State University, United States.
authors.forename: Erinn M
authors.initials: EM
authors.lastname: Hade
authors.affiliation: Department of Human Sciences, The Ohio State University, United States.
authors.forename: Sarah
authors.initials: S
authors.lastname: Schoppe-Sullivan
authors.affiliation: Department of Human Sciences, The Ohio State University, United States.
authors.forename: Claire
authors.initials: C
authors.lastname: Kamp Dush
authors.affiliation: The Institute for Behavioral Medicine Research, The Ohio State University Wexner Medical Center, United States; Division of Biosciences, The Ohio State University, United States.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Bailey
mesh_terms: D044822:Biodiversity; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005120:Extraversion, Psychological; D005243:Feces / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D007422:Intestines / Q000382:microbiology*; D008297:Male; D064307:Microbiota / Q000502:physiology*; D010802:Phylogeny; D012737:Sex Factors; D013694:Temperament / Q000502:physiology*
keywords: Childhood; Children; Early life; Gut microbiome; Gut–brain axis; Human; Mood; Stress; Temperament