Neighborhood walkability and body mass index in African American cancer survivors: The Detroit Research on Cancer Survivors study

Background: Extant evidence links neighborhood walkability with obesity-related health in the general population. This association likely exists in cancer survivors, but research is limited. Furthermore, a disproportionate obesity burden in African American cancer survivors warrants subgroup-specific analyses.

Methods: This study analyzed data from 2089 African American cancer survivors participating in the Detroit Research on Cancer Survivors (ROCS) cohort. On the basis of built environment data summarized within 1-km radial buffers around census block centroids, a multidimensional neighborhood walkability index (NWI) was constructed. Survivors' residential addresses at Detroit ROCS enrollment were geocoded, and addresses were linked to NWI scores via the census block of residence. At study enrollment, survivors reported height and weight; these data were used to calculate their body mass index (BMI). Associations between NWI quartiles and BMI overall and by cancer type, biological sex, and physical activity engagement were evaluated.

Results: BMI was found to be inversely associated with increasing NWI quartile (P for trend < .01). This inverse relationship was observed in men (P for trend < .01) and in survivors reporting any regular physical activity (P for trend < .01).

Conclusions: This study's findings suggest that among African American cancer survivors, higher neighborhood walkability is associated with lower BMI. As health care systems in the United States increasingly consider the role of the neighborhood environment in their patients' health, these findings provide additional evidence supporting health systems' incorporation of neighborhood walkability as an obesity-related health indicator for this cancer survivor subgroup and potentially for cancer survivors from other vulnerable populations.