Food environments and childhood weight status: effects of neighborhood median income.
BACKGROUND
A key aspect of any intervention to improve obesity is to better understand the environment in which decisions are being made related to health behaviors, including the food environment.


METHODS
Our aim was to examine the extent to which proximity to six types of food establishments is associated with BMI z-score and explore potential effect modification of this relationship. We used geographical information software to determine proximity from 49,770 pediatric patients' residences to six types of food establishments. BMI z-score obtained from the electronic health record was the primary outcome.


RESULTS
In multivariable analyses, living in closest proximity to large (β, -0.09 units; 95% confidence interval [CI], -0.13, -0.05) and small supermarkets (-0.08 units; 95% CI, -0.11, -0.04) was associated with lower BMI z-score; living in closest proximity to fast food (0.09 units; 95% CI, 0.03, 0.15) and full-service restaurants (0.07 units; 95% CI, 0.01, 0.14) was associated with a higher BMI z-score versus those living farthest away. Neighborhood median income was an effect modifier of the relationships of convenience stores and full-service restaurants with BMI z-score. In both cases, closest proximity to these establishments had more of an adverse effect on BMI z-score in lower-income neighborhoods.


CONCLUSIONS
Living closer to supermarkets and farther from fast food and full-service restaurants was associated with lower BMI z-score. Neighborhood median income was an effect modifier; convenience stores and full-service restaurants had a stronger adverse effect on BMI z-score in lower-income neighborhoods.
1Department of Gastroenterology and Nutrition, Boston Children's Hospital, Boston, MA.|2Division of General Academic Pediatrics, Department of Pediatrics, Massachusetts General Hospital for Children, Boston, MA.
Lauren
L
Fiechtner
2Division of General Academic Pediatrics, Department of Pediatrics, Massachusetts General Hospital for Children, Boston, MA.
Mona
M
Sharifi
3Partners Health Care System, Boston, MA.
Thomas
T
Sequist
4Obesity Prevention Program, Department of Population Medicine, Harvard Pilgrim Health Care Institute, Boston, MA.
Jason
J
Block
5Department of Population Health, New York University School of Medicine, New York, NY.
Dustin T
DT
Duncan
6Department of Environmental Health, Harvard School of Public Health, Boston, MA.
Steven J
SJ
Melly
4Obesity Prevention Program, Department of Population Medicine, Harvard Pilgrim Health Care Institute, Boston, MA.
Sheryl L
SL
Rifas-Shiman
2Division of General Academic Pediatrics, Department of Pediatrics, Massachusetts General Hospital for Children, Boston, MA.|7Department of Nutrition, Harvard School of Public Health, Boston, MA.
Elsie M
EM
Taveras
D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D004779:Environment Design / Q000706:statistics & numerical data*; D005260:Female; D005523:Food Supply / Q000706:statistics & numerical data*; D015438:Health Behavior; D006801:Humans; D007182:Income / Q000706:statistics & numerical data*; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D063766:Pediatric Obesity / Q000453:epidemiology / Q000517:prevention & control*; D012111:Residence Characteristics; D012147:Restaurants / Q000706:statistics & numerical data*; D012307:Risk Factors; D012931:Social Environment; D012959:Socioeconomic Factors; D016138:Walking / Q000706:statistics & numerical data