School Socioeconomic Composition and Adolescent Socioeconomic Status Interaction Effect, Physical Activity and School Lunch in Overweight and Obesity

Abstract

Background: Adolescent school socioeconomic composition (SEC) and socioeconomic status (SES) are negatively linked to overweight and obesity. No study has investigated the interaction effect between these two indicators. The main objective of this study is to investigate this relationship. Methods: 1038 adolescents from 11 public high-schools of the third biggest French region accepted to participate (response rate: 91.4%). They self-reported anthropomorphic variables, SES, school lunch and physical activity (PA) levels. The body mass index was divided into six categories according to the Centers for Control of Disease. Adjusted-multivariable binary logistic regressions analysis without and with interaction term were performed in overweight or obesity (overweight|obesity). Models fit was compared using the Aikake Information Criterion. Odds-ratio (OR) and their 95% accelerated-bootstrap confidence interval (95%BCa CI) were computed to estimate overweight|obesity risk. Findings: An interaction effect was observed between adolescent SES and school SEC. Among low-SES adolescents, we observed an absence of school-SEC effect. In contrast, medium-SES adolescents were at greater risk in low-SEC (OR=10.75, 95%BCa CI=2.67-64.57) and medium-SEC (OR=5.08, 95%BCa CI=1.55-24.84) compared with high-SEC schools. High-SES adolescents in low-SEC schools were at greater risk compared with those in medium-SEC (OR=5.94, 95%BCa CI=1.94-17.29) and high-SEC schools (OR=4.99, 95%BCa CI=1.71-13.14). A social gradient was observed in higher-SEC schools. In medium-SEC and high-SEC schools, low-SES adolescents were at greater risk compared with high-SES (OR=2.79, 95%BCa CI=1.22-7.41) and medium-SES (OR=6.86, 95%BCa CI=1.06-5.22*106) adolescents, respectively. Interpretation: Adolescent PA, lunch at- and outside-school help to understand these differences. Implications for obesity prevention initiatives are discussed. Funding Statement: The authors declare that have no funding for this research. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: The study was also approved by the Aix-Marseille University Ethics Committee (No. 2019-23-05-003).