Fast-food restaurants, park access, and insulin resistance among Hispanic youth

Background: Evidence of associations between the built environment and obesity risk has been steadily building, yet few studies have focused on the relationship between the built environment and aspects of metabolism related to obesity's most tightly linked comorbidity, type 2 diabetes.

Purpose: To examine the relationship between aspects of the neighborhood built environment and insulin resistance using accurate laboratory measures to account for fat distribution and adiposity.

Methods: Data on 453 Hispanic youth (aged 8-18 years) from 2001 to 2011 were paired with neighborhood built environment and 2000 Census data. Analyses were conducted in 2011. Walking-distance buffers were built around participants' residential locations. Body composition and fat distribution were assessed using dual x-ray absorptiometry and waist circumference. Variables for park space, food access, walkability, and neighborhood sociocultural aspects were entered into a multivariate regression model predicting insulin resistance as determined by the homeostasis model assessment.

Results: Independent of obesity measures, greater fast-food restaurant density was associated with higher insulin resistance. Increased park space and neighborhood linguistic isolation were associated with lower insulin resistance among boys. Among girls, park space was associated with lower insulin resistance, but greater neighborhood linguistic isolation was associated with higher insulin resistance. A significant interaction between waist circumference and neighborhood linguistic isolation indicated that the negative association between neighborhood linguistic isolation and insulin resistance diminished with increased waist circumference.

Conclusions: Reducing access to fast food and increasing public park space may be valuable to addressing insulin resistance and type 2 diabetes, but effects may vary by gender.