Wed, Jan 27: 10:00 AM
- 11:30 AM
No study to date has effectively linked health care utilization and costs with objective assessment of built environment and mode-specific physical activity. We examined how detailed urban form (within the home neighborhood) relates to objectively measured physical activity (PA) and health care costs while controlling for transit access, residential choices, attitudes/preferences, and sociodemographic factors. Unique and high-resolution data are harnessed for 476 participants in the Rails & Health study on health care costs, objective PA and travel behavior, built environment, and transportation/neighborhood perception surveys. Owing to the important methodological issue of potential dependencies among PA and health care cost outcomes arising from observed and unobserved factors, we used structural equation modeling (SEM). The direct effects of objectively measured built environment and PA on health care costs and the indirect effects of built environment on health costs mediated by mode-specific PA are quantified. A 1% increase in bike, walk, and transit-related moderate-to-vigorous PA (MVPA) was associated with lower health care costs by -0.28, -0.09, and -0.27 percent respectively (over a one-year period). A one-unit increase in walkability index (composite measure of intersection density, commercial floor area ratio, and land use mix) was associated with a substantial 6.48% reduction in health care costs. Significant indirect dependencies between residential choices, attitudes, preferences and health outcomes through physical activity were also observed. Methodologically, the results underscore the importance of accounting for unobserved factors that could jointly increase or decrease the mode-specific MVPA outcomes of a same participant.
Standing Committee on Transportation and Public Health
Behram Wali, Urban Design 4 Health, Inc.
Lawrence Frank, Urban Design 4 Health, Inc.
Deborah Young, Kaiser Permanente Southern California
Brian Saelens, University of Washington
Richard Meenan, Kaiser Permanente Northwest
John Dickerson, Kaiser Permanente Northwest
Erin Keast, Kaiser Permanente Northwest
Jennifer Kuntz, Kaiser Permanente Northwest
Stephen Fortmann, Kaiser Permanente Northwest