Change in Child Opportunity Index in Early Childhood Is Associated with Youth BMI Growth.

Background: The neighborhood-level child opportunity index (COI) has been used in policy-based initiatives to identify and improve low-resource neighborhoods in order to impact child health. Understanding of how changes in COI can impact child growth, however, is lacking. Methods: Participants were 1124 children from the Family Life Project, a longitudinal birth cohort of families in rural, high-poverty areas. Youth anthropometrics were measured at eight assessments (ages 2 months through 12 years). Neighborhood COI was obtained at seven assessments (ages 2 months through 5 years) and used to create seven trajectory groups representing a change in COI: stayed low on all seven assessments, stayed moderate, stayed high, left low, declined from moderate, declined from high, and bounced around. Results: As hypothesized, moving from high COI neighborhoods into lower COI neighborhoods was associated with greater BMI growth and increased risk for obesity and severe obesity at 12 years. As hypothesized, the opposite effect, which approached significance at p = 0.056, was found among children who moved from low COI neighborhoods into higher COI neighborhoods. Specifically, moving into higher COI neighborhoods was associated with reduced BMI growth, and lower risk for severe obesity at 12 years. Conclusions: Moving into higher COI neighborhoods may be associated with healthier BMI growth, while the opposite effect may occur when moving into lower COI neighborhoods. Given the use of the COI in public health initiatives and growing evidence for its potential positive impact on child growth, future work is needed to replicate our findings among larger diverse samples.