Relationship between body mass index and residential segregation in large cities of Latin America.

BACKGROUND: Obesity is a global health problem, and its connection with social and environmental factors is well-established. Social factors, such as urban segregation, may impact obesity through various mechanisms, including food and physical activity environments, as well as social norms and networks. This multilevel study aims to examine the effect of socio-economic residential segregation of Latin American cities on the obesity of individuals within those cities. METHODS: We analyzed data from national surveys for a total of 59,340 individuals of 18-70 years of age, conducted in 156 cities across Brazil, Chile, Colombia, and Mexico between 2007 and 2013. We adjusted two-level linear mixed models for body mass index (BMI) stratified by sex and country, controlling for age, educational level and poverty. Separate models were built for dissimilarity and isolation segregation indices. RESULTS: The relationships between segregation indices and BMI were mostly not statistically significant, and in some cases, they were opposite to what was expected. The only significant relationships were observed in Colombian men, using the dissimilarity index (-7.5 [95% CI: -14.4, -0.5]) and in Colombian women, using the isolation index (-7.9 [95% CI: -14.1, -1.7]). CONCLUSIONS: While individual-level factors cannot fully explain differences among people in the same city, segregation indices may help. However, we found that in some cases, the relationship between BMI and segregation indices is opposite to what is expected based on prior literature. This should be considered in examining the phenomenon. Further research on obesogenic environments in segregated neighborhoods could provide valuable evidence.

[The relation between overweight and obesity in preschool children with socioeconomic level and environment of Chilean districts: An ecological study]. / Relación entre el sobrepeso y la obesidad en menores de seis años y el nivel socioeconómico y las características del entorno en comunas de Chile: estudio ecológico.

OBJECTIVE: To analyze the association between the prevalence of overweight and obesity in children younger than six years of age cared for in the primary healthcare setting with socioeconomic level and environment of Chilean districts. METHODS: We conducted an ecological study to analyze the correlation between the prevalence of overweight and obesity and indicators of socioeconomic status (poverty by income and multidimensional poverty) and district environment and surroundings (green areas and crime reporting rate for crimes of significant social connotation). Furthermore, we performed four simple linear regression models with the correlated variables. RESULTS: At the district level, we found that the percentage of people living in poverty as defined by income, and the rate for reporting of crimes, are significantly correlated with the prevalence of overweight and obesity. The crime reporting rate correlated negatively with prevalence, and no correlation was found with communal green areas. Those districts with greater income poverty and a lower crime reporting rate have a higher prevalence of overweight and obesity in children under six years of age. CONCLUSIONS: The characteristics of the district environment in which children are raised could augment the risk for overweight and obesity, mainly due to socioeconomic level. The crime reporting rate, on the contrary, shows an inverse relationship with these nutritional conditions.

OBJETIVO: Analizar la asociación entre la prevalencia de sobrepeso y obesidad de los niños menores de seis años controlados en la atención primaria de salud, con medidas de nivel socioeconómico y de entorno de las comunas de Chile. MÉTODOS: Estudio ecológico que analiza la correlación entre la prevalencia de sobrepeso y obesidad e indicadores de nivel socioeconómico (pobreza por ingresos y pobreza multidimensional), y de entorno comunal (áreas verdes y tasa de denuncias de delitos de mayor connotación social). Además, se aplican cuatro modelos de regresión lineal simple con las variables correlacionadas. RESULTADOS: A nivel comunal se observa que el porcentaje de personas en condición de pobreza por ingresos y la tasa de denuncias se correlacionan de manera significativa con la prevalencia de obesidad y sobrepeso. La tasa de denuncias se correlaciona de manera negativa con la prevalencia de sobrepeso y obesidad, y no se encuentra correlación con las áreas verdes comunales. Aquellas comunas con mayor pobreza por ingresos y menor tasa de denuncias tienen mayor prevalencia de sobrepeso y obesidad en los menores de seis años. CONCLUSIONES: Las características del entorno comunal en el cual se desarrollan los niños/as podrían aumentar el riesgo de sobrepeso y obesidad, principalmente las características relacionadas con el nivel socioeconómico; las tasas de denuncias muestran en cambio, una relación inversa con estas condiciones nutricionales.