Abstract 12096: Satellite-Based Urbanization Measures Are Independent Predictors of Metabolic Syndrome

Abstract

Introduction: In India, with rapid urbanization, there is a significant increase in the prevalence of cardiovascular diseases at younger ages despite lower rates of obesity. While urbanization has led to nutrition transition, psychosocial stress and behavioral changes, these conventional risk factors do not fully explain the rapid increase in the prevalence. Hypothesis: Urbanization has had a profound impact on the physical environment leading to air pollution, urban heat islands and other effects, which are known to have an impact on metabolic health. Here we assess the impact of built environmental changes on the prevalence of metabolic syndrome (MS) in a rapidly urbanizing population in South India. Methods: Based on census data, a random sample included 8080 participants (20 to 76 years of age; 56% female) from urban, semi-urban, or rural areas spread over 80 x 80 kms. The MODIS satellite land cover data (urban, crops, trees, shrubs and grass land cover) at a 1 km x 1 km resolution was joined to participant's geolocated residential position in ArcGIS. Plus, the distance of the residential location to the urban center was mapped. MS was defined according to the AHA criteria. Multivariable regression models tested the independent association between MS and urban/built environment measures after adjusting for age, sex, physical activity, smoking, alcohol intake, socioeconomic, stress, anxiety, depression, family history of diabetes and hypertension, and energy intake levels. Results: The prevalence was higher in urban (44.6%) and semi-urban communities (35.2%) compared to rural (31.8%). In fully adjusted models, urban participants [OR: 2.11 (1.89, 2.36)], participants in urban land cover [OR: 1.57 (1.38, 1.78)) and those residing within 0 to 20 kms to the urban center [OR: 1.99 (1.7, 2.33)], had significantly higher odds for MS, when compared to rural, participants in crops land cover and those residing 60 to 80 kms from urban center, respectively. Conclusions: There is a significantly higher prevalence of MS in urban regions. After adjusting for traditional risk factors, there is an independent association between urbanization measures and MS suggesting unaccounted factors in the physical or built environment driving the prevalence MS in urban India.