Relationship between neighborhood social fragmentation and physical inactivity among adolescents living in Boston, Massachusetts

Background The purpose of this study was to identify the relationship between neighborhood social fragmentation and participation in moderate-to-vigorous physical activity among 1,878 urban adolescents living in 38 neighborhoods participating in the 2008 Boston Youth Survey (BYS), which is a biennial survey of high school students (grades 9-12).

Methods We used 2010 US Census data to characterize each participant's residential neighborhood. Social fragmentation was composed of the indicators: proportion of residents who have lived in the same house less than 5 years, proportion of vacant house units, and proportion of owner occupied housing (reverse coded). The 75th percentile was used as the threshold for high social fragmentation. Multilevel regression models were used to determine the association between social fragmentation and inactivity (no reported participation in vigorous physical activity) while controlling for individual-level characteristics: sex, race, age, and immigrant status and neighborhood-level factors: economic deprivation, social cohesion, danger, and disorder.

Results High social fragmentation within the residential neighborhood was associated with an increased likelihood of being inactive (OR=1.51, 95% CI=1.11, 2.06). No other neighborhood exposures were associated with physical inactivity. Girls, racial/ethnic minorities and older teens had higher odds of reporting no vigorous physical activity than boys, white youth and 14 year olds, respectively.

Conclusion Neighborhood-level factors, such as social fragmentation may be important determinants of physical inactivity, especially among youth living in urban settings. Providing opportunities and resources for physical activity might not be sufficient. Interventions might also include creating stable and supportive environments for youth to be physically active.