Abstract 14842: Satellite Based Urban Land Cover and Proximity to Urban Center are Independent Predictors of Hypertension in a Southeast Asian Population
Background: Urbanization is linked to higher prevalence of cardiovascular disease (CVD). Hypertension (HTN) is a major risk factor for CVD. In this study we assess the impact of urbanization on prevalence of HTN in a population-based study in South India.
Methods: In the cross-sectional analysis 8080 participants (mean age 42 years; 58% women) spread over 65 x 80 km area constituted the study sample. MODIS satellite derived land cover data at a 1 km x 1 km resolution was obtained and joined to each participant’s geolocated residential position in ArcGIS to assign urban and rural (crops, trees, shrubs and grass land cover) designations. Simultaneously, participants’ residential position in relation to urban center was assessed. The study included sytolic (SBP) and diastolic (DBP) blood pressure, anthropometric, socioeconomic, psycosocial, physcial activity assessemnts and blood work. HTN was defined as SBP ≥ 140 or DBP ≥ 90 or reported history of HTN.
Results: Based on the land cover data the mean SBP and DBP (mmHg) in men (SBP: 131 ± 21; DBP: 81 ± 12) and women (SBP: 125 ± 20; DBP: 77 ± 11) living in urban environment were significantly higher when compared to men (SBP: 122 ± 18; DBP: 77 ± 11) and women (SBP: 117 ± 18; DBP: 74 ± 10) in rural environments [p < 0.001]. There was a significantly higher prevalence of HTN in urban men (42.1%) when compared to rural men (26.4%) [p < 0.001]. Similarly, the prevalence of HTN was higher in urban women (28.3%), when compared to rural women (19.1%) [p < 0.001]. After controlling for age, BMI, smoking, blood sugar, LDL and socioeconomic, physical activity, anxiety and stress levels, both men (OR = 1.94; 95% CI: 1.64, 2.9) and women (OR = 1.51; 95% CI: 1.28, 1.8) living in urban land cover were more likely to have HTN compared to those living in non-urban land cover. In the proximity analysis after multivariate adjustments, men (OR = 2.25; 95%CI: 1.78, 2.83) and women (OR = 1.87; 95%CI: 1.47, 2.38) residing within 0-20 km distance from urban center had significantly higher odds of HTN than the 60-80 km reference group.
Conclusions: Living in an urban environment is associated with increased prevalence of HTN independent of other risk factors. Future research is needed to determine what components of the urban environment contribute to increased levels of HTN.
Author Disclosures: M. Thanikachalam: None. K.J. Lane: None. J. Sunderarajan: None. V. Harivanzan: None. S. Thanikachalam: None.
- © 2014 by American Heart Association, Inc.