Neighborhood features that influence children's BMI may change as children matureThe impact of environmental characteristics on children's weight is becoming an increasingly popular area of study, however, most studies to date have examined relationships at one-point in time (cross-sectional design) and have reported inconsistent findings. The purpose of this study was to deepen understanding of associations between objectively-measured neighborhood characteristics and weight in children and their female caregivers.
In this study, Timperio and colleagues examined both cross-sectional and longitudinal relationships between physical activity-related neighborhood features and weight among 140 5- to 6-year-old and 269 10- to 12-year-old children from Melbourne, Australia and their female caregivers in 2001 and 2004. Researchers collected information on participants' height and weight and used a geographic information system (GIS) to assess various physical activity-related neighborhood features (e.g., access to public open spaces, density of cul-de-sacs and intersections, length of busy roads, etc.) within 800m and 2km of each child's residence.
In analyzing the data, Timperio and colleagues did not find many neighborhood features that were associated with children's weight or weight changes. Significant relationships that they did discover, however, were different for younger and older children and were not consistent among cross-sectional (single-year) and longitudinal (across 3 years) analyses. For example, older children who lived in neighborhoods with a higher density of public open spaces dedicated as sport/recreation, had lower BMIs, however, these findings did not hold up when examined longitudinally (across the 3 years).
Timperio and colleagues believe that these findings suggest that important features may change as children mature. Researchers' use of objective neighborhood measures and a longitudinal design provide an important contribution to the literature. Further, this is one of the few studies to examine children and adults simultaneously. Additional research is needed to identify physical-activity related environmental factors that consistently impact children's weight status and thus can be a target of design interventions.
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