摘要：Objectives. To determine whether proximity to a supermarket modified the effects of an obesity intervention. Methods. We examined 498 children aged 6 to 12 years with a body mass index (BMI) at or above the 95th percentile participating in an obesity trial in Massachusetts in 2011 to 2013. The practice-based interventions included computerized clinician decision support plus family self-guided behavior change or health coaching. Outcomes were 1-year change in BMI z -score, sugar-sweetened beverage intake, and fruit and vegetable intake. We examined distance to the closest supermarket as an effect modifier. Results. Distance to supermarkets was an effect modifier of 1-year change in BMI z- score and fruit and vegetable intake but not sugar-sweetened beverage intake. With each 1-mile shorter distance to a supermarket, intervention participants increased their fruit and vegetable intake by 0.29 servings per day and decreased their BMI z- score by −0.04 units relative to controls. Conclusions. Living closer to a supermarket is associated with greater improvements in fruit and vegetable intake and weight status in an obesity intervention. The prevalence of childhood obesity remains high despite public health and clinical efforts to prevent and manage obesity. 1 Evidence suggests that the etiology and, thus, prevention of obesity may be influenced by the food, beverage, and physical activity environments of children. Understanding the role of environmental factors in obesity and developing interventions to change default environments may have important effects on reductions in obesity incidence and prevalence and public health. Mounting evidence suggests that aspects of the built environment, including access to healthful food establishments, may facilitate behavior change and improve weight status. For example, studies have shown protective associations of living closer to supermarkets with children’s dietary behaviors and body mass index (BMI). 2–5 Because families face budget and time constraints, living closer to a large supermarket could assist families in making healthy dietary and BMI changes by increasing access to affordable healthy food and beverages available in these establishments. Furthermore, the Centers for Disease Control and Prevention has endorsed increasing the number of supermarkets in underserved areas as 1 of the 24 strategies to help communities prevent obesity. 6 Additionally, in 2010 the White House Childhood Obesity Task Force emphasized the need to improve access to fresh, healthy, affordable food by eliminating “food deserts”—defined as neighborhoods without access to fresh, healthy, and affordable food. 7,8 Although cross-sectional and longitudinal studies support the protective effect of easy access to supermarkets on children’s obesity risk, few studies have examined the modifying effects of the food environment, particularly supermarkets, in facilitating BMI and behavior change in a childhood obesity randomized controlled trial. We examined the extent to which living closer to supermarkets modified the effects of a childhood obesity randomized controlled trial on changes in BMI and diet. We hypothesized that children in the obesity intervention who lived closer to a large supermarket would have greater decreases in their BMI z- score and their intakes of sugar-sweetened beverages (SSBs) and a greater increase in their fruit and vegetable intake than would those living farther away.
