Relationship between breast-feeding and adiposity in infants and pre-school children.

OBJECTIVES: We aimed to establish associations of duration of breast-feeding with mean BMI and waist circumference, as well as the likelihood of being overweight/obese, during early childhood. DESIGN: Cross-sectional, population-based study. Height, weight and waist circumference were measured and BMI calculated. Interviewer-administered questionnaire determined whether the child was ever breast-fed and the duration of breast-feeding. SETTING: Sydney, Australia. SUBJECTS: Infants and pre-school children (n 2092) aged 1-6 years were examined in the Sydney Paediatric Eye Disease Study during 2007-2009. RESULTS: Of the children aged 1-6 years, 1270 had been breast-fed compared with 822 who were never breast-fed. After multivariable adjustment, 1-6-year-old children who were ever breast-fed compared with those who were not had significantly lower BMI, 16·7 (se 0·1) kg/m2 v. 17·1 (se 0·2) kg/m2 (P = 0·01). Decreasing BMI was associated with increasing duration of breast-feeding (P trend = 0·002). After multivariable adjustment, each month increase in breast-feeding was associated with an average BMI decrease of 0·04 kg/m2 (P = 0·002) and 0·03 kg/m2 (P = 0·03) among children aged 1-2 years and 3-4 years, respectively. In 1-2-year-old children, each month increase in breast-feeding duration was associated with a 0·06 cm decrease in waist circumference (P = 0·04). Significant associations were not observed among 5-6-year-old children. Children who were ever breast-fed v. those never breast-fed were less likely to be overweight/obese (multivariable-adjusted OR = 0·54; 95 % CI 0·36, 0·83). CONCLUSIONS: We demonstrated a modest influence of breast-feeding on children's BMI during early childhood, particularly among those aged less than 5 years.

Body mass index and waist circumference are associated with blood pressure in preschool-aged children.

PURPOSE: Population-derived data on the association between body mass index (BMI) and blood pressure (BP) during early childhood are lacking. We investigated the association between BMI, waist circumference, and BP among preschool-aged children. METHODS: A total of 1294 children ages 3 to 6 years were examined in the Sydney Paediatric Eye Disease Study during 2007 to 2009. Height, weight, and waist circumference were collected and BMI calculated. The weight status of each child was classified on the basis of age- and sex-specific BMI percentiles. BP was measured by the use of a standard protocol. RESULTS: A prevalence of 11.0% and 15.1% of children were obese or overweight, respectively. The prevalence of elevated BP was 21.3% among obese children compared with 12.4% of nonoverweight/obese children (p = .03). An increase of 1 BMI unit was independently associated with, on average, a 0.57 and 0.56 mm Hg increase in systolic and diastolic BP, respectively. Each unit increase in waist circumference was associated with a 0.14 and 0.23 mm Hg increase in systolic and diastolic BP, respectively. CONCLUSIONS: A strong and independent association between adiposity and BP was present during early childhood. These data have important public health implications because elevated BP at a young age may be associated with increased cardiovascular risk in later life.