title: Determinants of rapid weight gain during infancy: baseline results from the NOURISH randomised controlled trial.
abstract: BACKGROUND
  Rapid weight gain in infancy is an important predictor of obesity in later childhood. Our aim was to determine which modifiable variables are associated with rapid weight gain in early life.
  
  
  METHODS
  Subjects were healthy infants enrolled in NOURISH, a randomised, controlled trial evaluating an intervention to promote positive early feeding practices. This analysis used the birth and baseline data for NOURISH. Birthweight was collected from hospital records and infants were also weighed at baseline assessment when they were aged 4-7 months and before randomisation. Infant feeding practices and demographic variables were collected from the mother using a self administered questionnaire. Rapid weight gain was defined as an increase in weight-for-age Z-score (using WHO standards) above 0.67 SD from birth to baseline assessment, which is interpreted clinically as crossing centile lines on a growth chart. Variables associated with rapid weight gain were evaluated using a multivariable logistic regression model.
  
  
  RESULTS
  Complete data were available for 612 infants (88% of the total sample recruited) with a mean (SD) age of 4.3 (1.0) months at baseline assessment. After adjusting for mother's age, smoking in pregnancy, BMI, and education and infant birthweight, age, gender and introduction of solid foods, the only two modifiable factors associated with rapid weight gain to attain statistical significance were formula feeding [OR = 1.72 (95%CI 1.01-2.94), P = 0.047] and feeding on schedule [OR = 2.29 (95%CI 1.14-4.61), P = 0.020]. Male gender and lower birthweight were non-modifiable factors associated with rapid weight gain.
  
  
  CONCLUSIONS
  This analysis supports the contention that there is an association between formula feeding, feeding to schedule and weight gain in the first months of life. Mechanisms may include the actual content of formula milk (e.g. higher protein intake) or differences in feeding styles, such as feeding to schedule, which increase the risk of overfeeding.
  
  
  BACKGROUND
  Australian Clinical Trials Registry ACTRN12608000056392.
authors: School of Public Health, Queensland University of Technology, Brisbane, Australia. l2.daniels@qut.edu.au
authors: Seema
authors: S
authors: Mihrshahi
authors: Diana
authors: D
authors: Battistutta
authors: Anthea
authors: A
authors: Magarey
authors: Lynne A
authors: LA
authors: Daniels
mesh_terms: D000328:Adult; D001835:Body Weight / Q000502:physiology*; D001942:Breast Feeding; D005260:Female; D005500:Follow-Up Studies; D005518:Food Preferences / Q000502:physiology*; D006801:Humans; D007223:Infant; D007225:Infant Food; D007227:Infant Nutritional Physiological Phenomena; D008297:Male; D009765:Obesity / Q000209:etiology; D011247:Pregnancy; D011379:Prognosis; D012189:Retrospective Studies; D015430:Weight Gain / Q000502:physiology*