Association of neighborhood Walk Score with accelerometer-measured physical activity varies by neighborhood socioeconomic status in older women

The built environment can influence physical activity behavior. Walk Score is a widely used measure of the neighborhood built environment to support walking. However, studies of the association between Walk Score and accelerometer-measured physical activity are equivocal and no studies have examined this relationship among older adults. We analyzed data from a large, diverse sample of women (n = 5650) with a mean age of 79.5 (SD = 6.7) at time of accelerometry wear in the Women's Health Initiative Objective Physical Activity Cardiovascular Health Study in the United States to examine associations between neighborhood Street Smart Walk Score (SSWS) and accelerometer-measured physical activity. Participants wore triaxial accelerometers for seven days and SSWS was determined from home addresses. 67 % of the sample lived in car-dependent locations (SSWS 0-49 out of 100); only 3 % lived in walker's paradise locations (SSWS 90-100). The multivariable model indicated an association between SSWS and accelerometer-measured physical activity (steps/day) in the total sample. The association varied by neighborhood socioeconomic status; in high socioeconomic status neighborhoods, higher SWSS was associated with greater steps per day, while no significant association between SWSS and physical activity was observed in low socioeconomic neighborhoods. This study should catalyze furtherresearch regarding the utility of SSWS in determining neighborhood walkability for older women across different neighborhood settings and suggests other built environment factors must be considered when determining walkability. Future studies should examine what factors influence walkability and develop age-relevant methods to assess and characterize neighborhood walkability.