Preventing obesity in children, especially those from Aboriginal and Torres Strait Islander backgrounds is a national priority.  Recent national data suggests higher rates of overweight/obesity among Indigenous pre-schoolers (28.1%) than non-Indigenous pre-schoolers (20.5%) (1). Previous studies also suggest Indigenous children residing in urban areas tend to be heavier and taller than those residing in rural/remote areas. Two regional studies, based in the Northern Territory, found both high proportions of underweight and overweight children in urban areas (2,3).

The Gudaga Study is a longitudinal birth cohort of 159 Australian Aboriginal children born on the urban fringe of Sydney. Birthweight and length were extracted from hospital data. Children with a birthweight >1500 grams were included in the analysis (n=157). Weight, length, and head circumference were measured at 2-3 weeks and then six monthly until 24 months of age. Age and gender specific standard deviation (SD) scores were determined from the CDC 2000 growth charts for weight, length, head circumference and body mass index (BMI). The proportion of children experiencing RWG (an increase of ≥0.67 SD weight-for-age in first year) was calculated. The association between RWG and ≥85^th CDC percentile for BMI at 24 months was tested using Pearson’s Chi Square.

Gudaga infants were lighter than CDC standards at birth and 2-3 weeks of age, but heavier than CDC standards by 18 and 24 months of age. Overall, 42 infants (34.4%) experienced RWG and 45 infants (36.9%) were overweight/obese at 24 months of age. Infants who experienced RWG in the first year of life (n=26, 61.9%) were significantly more likely to be overweight or obese at 24 months compared with those who did not experience RWG (n=19, 23.8%) (χ₁²=17.2, p<0.001).

Our study suggests a concerning proportion of urban Aboriginal infants experience RWG and overweight/obesity in early childhood.