Air pollution, noise, green spaces and built environment and the risk of overweight and obesity during childhood

Abstract

OPS 31: Health effects of multiple environmental stressors, Room 412, Floor 4, August 27, 2019, 1:30 PM - 3:00 PM Background/Aim: Recent studies have linked air pollution, noise, green spaces and built environment with childhood overweight/obesity. However, few have evaluated multiple urban exposures in one study. The aim is to evaluate whether the urban environment is associated with the risk of developing overweight and obesity during childhood (between 3 and 9 years old). Methods: A longitudinal study included children (n=112.734) identified at 4 years (±1 year) from primary care records (SIDIAP) between 01/01/2011 and 31/12/2013. They were followed up until 31/12/2016, death or transferred-out. Height/weight were measured several times during childhood and BMI was calculated (kg/m2). Overweight/obesity was categorized following the WHO reference. The urban indicators were calculated at census tract level. The estimated urban indicators were air pollution (nitrogen dioxides (NO2), particulate matter <10μm (PM10) and < 2.5μm (PM2.5)), noise, green spaces (Normalized Difference Vegetation Index (NDVI) and % green space) and built environment (population density, intersection density, mixed land use and walkability index). Hazard ratios (HR) were calculated using a multivariable Cox model to explore the association between the urban environment and the risk of developing overweight/obesity. Results: We found that an interquartile (IQR) increase of NO2 (26.5 μg/m3), PM10 (8.1 μg/m3), population density (29877 people/km2) and intersection density (194.0 intersections/km2) increased the risk of developing overweight/obesity during childhood [NO2 HR=1.04; (95%CI, 1.02-1.06); PM10 HR=1.02; (1.00-1.04); population HR=1.04; (1.03-1.05); intersection HR=1.03; (1.02-1.04)]. Further, an IQR of NDVI (0.2 units), % green spaces (41.1% units), noise (5.2 dB(A)) and mixed land use (0.4 units) decreased the risk of developing overweight/obesity [NDVI HR=0.96; (0.94-0.98); %green HR=0.97; (0.94-0.99); noise HR=0.97; (0.95-0.99); mixed land use HR=0.96; (0.95-0.98)]. We did not found significant association for PM2.5 and walkability score. Conclusions: This study provides preliminary results on the influence of air pollution, noise, green spaces and built environment on the development of childhood overweight/obesity.