Is the number of fast-food outlets in the neighbourhood related to screen-detected type 2 diabetes mellitus and associated risk factors?

OBJECTIVE We investigated whether a higher number of fast-food outlets in an individual's home neighbourhood is associated with increased prevalence of type 2 diabetes mellitus and related risk factors, including obesity. DESIGN Cross-sectional study. SETTING Three UK-based diabetes screening studies (one general population, two high-risk populations) conducted between 2004 and 2011. The primary outcome was screen-detected type 2 diabetes. Secondary outcomes were risk factors for type 2 diabetes. SUBJECTS In total 10 461 participants (mean age 59 years; 53% male; 21% non-White ethnicity). RESULTS There was a higher number of neighbourhood (500 m radius from home postcode) fast-food outlets among non-White ethnic groups (P<0.001) and in socially deprived areas (P<0.001). After adjustment (social deprivation, urban/rural, ethnicity, age, sex), more fast-food outlets was associated with significantly increased odds for diabetes (OR=1.02; 95% CI 1.00, 1.04) and obesity (OR=1.02; 95% CI 1.00, 1.03). This suggests that for every additional two outlets per neighbourhood, we would expect one additional diabetes case, assuming a causal relationship between the fast-food outlets and diabetes. CONCLUSIONS These results suggest that increased exposure to fast-food outlets is associated with increased risk of type 2 diabetes and obesity, which has implications for diabetes prevention at a public health level and for those granting planning permission to new fast-food outlets.