title: Child-care use and the association with body mass index and overweight in children from 7 months to 2 years of age.
abstract: OBJECTIVE
  Studies regarding the association of child-care use with body mass index (BMI), overweight or obesity development show contradictory results. This study examined the relationship between child-care use and BMI z-scores and overweight, as well as associates of child-care use in children up to 2 years old.
  
  
  METHODS
  Longitudinal data originated from the Dutch KOALA Birth Cohort Study. Questionnaires assessed child-care use at ages 7 months and 1 and 2 years (N=2396). Height and weight assessed at 1 and 2 years were used to calculate BMI z-scores. Overweight was defined as a BMI z-score of ≥85th percentile. The influence of child-care use on weight development was tested using backward linear and logistic regression analyses. Outcomes were: (1) BMI z-score at 1 and 2 years; (2) change in BMI z-score between 1 and 2 years; (3) overweight vs non-overweight at 1 and 2 years; and (4) change from normal weight to overweight vs remaining normal weight between 1 and 2 years. The association between child-care use and parental background characteristics was tested using backward logistic regression analyses.
  
  
  RESULTS
  Child-care use (no/yes) at 1 and 2 years positively predicted BMI z-scores at age 2 years, as well as change in BMI z-score between 1 and 2 years. These associations were adjusted for various covariates (for example, parental working hours). Furthermore, child-care use significantly increased the odds of being overweight at age 1 year. There were few differences in BMI or overweight between intensive (>16 h per week) and limited child-care use (≤16 h). Child-care use was positively associated with various parental characteristics, including parental working hours and maternal educational level.
  
  
  CONCLUSIONS
  The findings suggest a small influence of child-care use on weight development in very young children. The child-care setting could have an important role in preventive interventions against overweight and obesity development in young children.
authors.affiliation: Department of Health Promotion, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands. jessica.gubbels@gvo.unimaas.nl
authors.forename: J S
authors.initials: JS
authors.lastname: Gubbels
authors.forename: S P J
authors.initials: SP
authors.lastname: Kremers
authors.forename: A
authors.initials: A
authors.lastname: Stafleu
authors.forename: P C
authors.initials: PC
authors.lastname: Dagnelie
authors.forename: N K
authors.initials: NK
authors.lastname: de Vries
authors.forename: S
authors.initials: S
authors.lastname: van Buuren
authors.forename: C
authors.initials: C
authors.lastname: Thijs
mesh_terms: D015992:Body Mass Index; D002654:Child Care / Q000706:statistics & numerical data*; D002657:Child Development; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D009765:Obesity / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D016017:Odds Ratio; D011446:Prospective Studies; D018570:Risk Assessment