title: Infant antibiotic exposure and the development of childhood overweight and central adiposity.
abstract: BACKGROUND
  Obesity has been associated with disruption of the gut microbiota, which is established during infancy and vulnerable to disruption by antibiotics.
  
  
  OBJECTIVE
  To investigate the association between early-life antibiotic exposure and subsequent development of overweight and central adiposity.
  
  
  METHODS
  Provincial health-care records were linked to clinical and survey data from a Canadian longitudinal birth cohort study. Antibiotic exposure during the first year of life was documented from prescription records. Overweight and central adiposity were determined from anthropometric measurements at ages 9 (n=616) and 12 (n=431). Associations were determined by multiple logistic regression.
  
  
  RESULTS
  Infants receiving antibiotics in the first year of life were more likely to be overweight later in childhood compared with those who were unexposed (32.4 versus 18.2% at age 12, P=0.002). Following adjustment for birth weight, breastfeeding, maternal overweight and other potential confounders, this association persisted in boys (aOR 5.35, 95% confidence interval (CI) 1.94-14.72) but not in girls (aOR 1.13, CI 0.46-2.81). Similar gender-specific associations were found for overweight at age 9 (aOR 2.19, CI 1.06-4.54 for boys; aOR 1.20, CI 0.53-2.70 for girls) and for high central adiposity at age 12 (aOR 2.85, CI 1.24-6.51 for boys; aOR 1.59, CI 0.68-3.68 for girls).
  
  
  CONCLUSIONS
  Among boys, antibiotic exposure during the first year of life was associated with an increased risk of overweight and central adiposity in preadolescence, indicating that antibiotic stewardship is particularly important during infancy. Given the current epidemic of childhood obesity and the high prevalence of infant antibiotic exposure, further studies are necessary to determine the mechanisms underlying this association, to identify the long-term health consequences, and to develop strategies for mitigating these effects when antibiotic exposure cannot be avoided.
authors.affiliation: 1] Pediatrics, University of Alberta, Edmonton, Alberta, Canada [2] Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba, Canada [3] Manitoba Institute of Child Health, Winnipeg, Manitoba, Canada.
authors.forename: M B
authors.initials: MB
authors.lastname: Azad
authors.affiliation: Pediatrics, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: S L
authors.initials: SL
authors.lastname: Bridgman
authors.affiliation: 1] Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba, Canada [2] Manitoba Institute of Child Health, Winnipeg, Manitoba, Canada.
authors.forename: A B
authors.initials: AB
authors.lastname: Becker
authors.affiliation: 1] Pediatrics, University of Alberta, Edmonton, Alberta, Canada [2] School of Public Health, University of Alberta, Edmonton, Alberta, Canada [3] Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: A L
authors.initials: AL
authors.lastname: Kozyrskyj
mesh_terms: D017668:Age of Onset; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects*; D015992:Body Mass Index; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D064307:Microbiota / Q000187:drug effects* / Q000276:immunology; D056128:Obesity, Abdominal / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors; D015430:Weight Gain / Q000187:drug effects* / Q000276:immunology
chemical_list: D000900:Anti-Bacterial Agents