4 October 2006 Dear Editor, PREVALENCE OF OVERWEIGHT AND OBESITY IN A REGIONAL QUEENSLAND PRESCHOOL POPULATION The reported trend of increasing overweight and obesity among Australian school children1 has resulted in studies of younger children being undertaken in recent years in an attempt to determine the age at which this trend begins. Identifying age of onset may be an important factor in understanding the ‘obesogenic’ factors that lead to this condition. The rebound or increase in body mass index (BMI) that occurs after it reaches its lowest point in early childhood is referred to as ‘adiposity rebound’ (AR). The age at which children enter the phase of AR (usually 5–6 years) generally coincides with entry into the preschool system. An early AR has been shown to be associated with an increased risk of obesity in adulthood.2 The detection of an increased prevalence of overweight or obesity in preschool children may offer opportunities for research to determine the environmental factors associated with an early AR. Results of studies determining the BMI of preschool children from South Australia and Victoria have previously been reported.3, 4 These studies encouraged us to explore the incidence of overweight and obesity in our regionally based preschool population. Our research called the ‘Toowoomba Healthy Weight Study’ surveyed a cohort of preschool children attending State primary schools with collocated preschool in our regional Queensland district. We obtained ethics approval for this study from the Toowoomba Health Service ethics committee and from Education Queensland. Weight and height of 339 children was measured with informed parental consent by a single observer in Term 4 of 2005. Age ranged from 4.0 to 6.5 (mean 5.2 ± 0.3) years. BMI and the age of the child on the day of measurement were calculated and the age and gender-specific International Obesity Task Force cut-off points5 were used to classify overweight and obesity. Of the 182 boys and 157 girls measured, 89% were aged between 5.0 and 5.5 years. Overall, 18.3% of all children were overweight or obese. This figure is similar to the overall prevalence of 19.3% and 19.8% found in the South Australian and Victorian studies respectively. Table 1 shows the percentages of overweight, obese and combined overweight/obese children in the South Australian, Victorian studies and the Toowoomba Healthy Weight Study (permission was obtained from the author and publisher to amend and add our data to their previously published table4). Despite differences in sample size and sampling frames between the three studies, the results confirm a trend which affects preschool children in regional and metropolitan areas across these three states. A limitation to our study is that the results reflect the prevalence of overweight and obesity in children attending State schools with collocated preschool in our district and do not include children from non-State institutions. In addition, the number of children consented by their parents to participate in the study was 37% of the total cohort of children at these preschools. Despite these limitations, our findings that approximately one in five preschoolers in our district is already overweight or obese add to the alarming evidence of excessive weight gain in Australian preschool children affecting girls more so than boys. These data support the need to develop national awareness, educational, supportive and preventative programmes targeting families with young children to prevent these children from becoming overweight and/or obese. This research was funded by the Toowoomba Hospital Foundation and the Pure Land Learning College, Toowoomba.
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