Association Between School Neighborhood Environment And Obesity Among School-aged Childrenin Japan

Many cases of childhood obesity transition to adult obesity, which is a risk factor for lifestyle-related diseases and death. The neighborhood environment is essential for children because children’s health-related activities have a limited range. PURPOSE: The study aim was to clarify the association between the school neighborhood environment and obesity among school-aged children in Japan. METHODS: A total of 21,491 5th- to 12th-grade students from 76 schools covering all regions of Japan were included in the study. Grade, sex, height, and weight were assessed using questionnaires, and percent overweight (POW) was calculated. A POW ≥20% was considered obese. Using the geographic information system, one type of socioeconomic environmental factor, three types of natural environmental factors, and eleven types of built environmental factors in the school neighborhood were investigated. A multilevel logistic regression analysis was performed. All analyses were conducted by school type, with obesity as the objective variable. Adjustments were made for grade, sex, and school governing body. First, in a model with one neighborhood environment factor as an explanatory variable respectively, potentially relevant variables were extracted with a criterion of p < 0.20. Next, neighborhood environment factors with p-values of <0.20 in the respective models were simultaneously entered as explanatory variables; p-values were adjusted for false discovery rate, and an adjusted p-value of <0.05 was considered statistically significant. RESULTS: Among elementary school students only, the area deprivation index (ADI)—a socioeconomic environment factor—showed a significant positive association (OR = 1.15; adjusted p = 0.045). In a subgroup analysis dichotomizing target elementary schools by ADI, ADI showed a significant positive association only in school neighborhoods with high ADI (OR = 1.21; adjusted p = 0.006). None of the neighborhood environmental factors were significantly associated with obesity among junior high and high school students. CONCLUSIONS: The neighborhood socioeconomic environment was suggested to play an important role in obesity among elementary school students. Elementary school students from neighborhoods with notably low socioeconomic status appear to be at a high risk for obesity. This work was supported by JSPS KAKENHI Grant Number JP 18H01000, JSPS KAKENHI Grant Number JP 19 K21797, JSPS KAKENHI Grant Number JP 21H00848, JSPS KAKENHI Grant Number JP 22 J11000, and Spring! Doshisha.