Obesity research should examine socioeconomically-driven built environments impacting daily energy intake/expenditure. Research results are mixed, particularly due to varying study designs, needs for complex statistical models, direct environment audits, and population sub-group analyses. This study investigated how directly measured built environment and obesity factors were related in residents of 21 urban/suburban neighborhoods.
Participants were 565 adults (69.8% female, ages 45.2±14.7 years). Stratified random selection of census block groups resulted in 7 per income tertile. In-person household surveys were conducted; height and weight were directly measured. The Census of Social Institutions was used to directly assess all non-residential land parcels within 1-mile of block group centers.
Body mass index (BMI) range was 13.2-66.3 kg/m2, obesity prevalence was 34.2% (8.7% to 61.5% by block group), and 62.7% of participants were overweight or obese.Obesity prevalence was significantly related to block-group income, with lower income groups having higher obesity (38.3%, χ2=10.5; p<0.05). Obesity was positively associated with block groups with the highest proportions of minorities (55.4%, χ2=13.9; p<0.05). BMI was positively correlated with fast-food restaurants (r=0.8, p<0.05) and negatively correlated with full-service restaurants (r=-0.9, p<0.05) and gyms/fitness centers (r=-0.9, p<0.05) in low income block groups. Multilevel modeling found greater obesity risk for males (OR=2.6), those with more poor health days (OR=1.1), and fewer exercise/biking paths (OR=1.1). Female minorities (OR=2.8) and white males (OR=2.6) had higher obesity risk than white females.
Directly measured data provided further evidence of built environment relationship and obesity, with surprising findings for males. Access to health promoting, rather than health compromising resources, is related to lower obesity. Future research should examine causality from built environment changes.