Changes in the built environment and changes in the amount of walking over time: longitudinal results from the multi-ethnic study of atherosclerosis

Abstract

Lack of longitudinal research hinders causal inference on the association between the built environment and walking. In the present study, we used data from 6,027 adults in the Multi-Ethnic Study of Atherosclerosis who were 45-84 years of age at baseline to investigate the association of neighborhood built environment with trends in the amount of walking between 2000 and 2012. Walking for transportation and walking for leisure were assessed at baseline and at 3 follow-up visits (median follow-up = 9.15 years). Time-varying built environment measures (measures of population density, land use, number of destinations, bus access, and street connectivity) were created using geographic information systems. We used linear mixed models to estimate the associations between baseline levels of and a change in each built environment feature and a change in the frequency of walking. After adjustment for potential confounders, we found that higher baseline levels of population density, area zoned for retail, social destinations, walking destinations, and street connectivity were associated with greater increases in walking for transportation over time. Higher baseline levels of land zoned for residential use and distance to buses were associated with less pronounced increases (or decreases) in walking for transportation over time. Increases in the number of social destinations, the number of walking destinations, and street connectivity over time were associated with greater increases in walking for transportation. Higher baseline levels of both land zoned for retail and walking destinations were associated with greater increases in leisure walking, but no changes in built environment features were associated with leisure walking. The creation of mixed-use, dense developments may encourage adults to incorporate walking for transportation into their everyday lives.

Keywords: environment design; geographic information systems; leisure activities; longitudinal/prospective studies; neighborhoods; residence characteristics; transportation; walking.

Figure 1.

Associations of baseline measures of and changes in built environment characteristics with annual changes in walking for transportation, Multi-Ethnic Study of Atherosclerosis, 2000–2012. The open circles denote the mean difference in annual walking (minutes per week per year) for a 1-standard-deviation higher score for the built environment measure at baseline. The black circles denote the mean difference in annual walking (minutes per week per year) for a 1-standard-deviation increase in the change in the built environment feature over time. Estimates were from models that were controlled for baseline built environment measures, changes in built environment, time (in years), baseline age, an interaction between baseline age and time, sex, race, an interaction between race and time, educational level, income, employment, marital status, car ownership, cancer, arthritis, body mass index, self-rated health compared with others, and site.

Figure 2.

Associations of baseline measures of and changes in built environment characteristics with annual changes in walking for leisure, Multi-Ethnic Study of Atherosclerosis, 2000–2012. The open squares denote the mean difference in annual walking (minutes per week per year) for a 1-standard-deviation higher score for the built environment measure at baseline. The black squares denote the mean difference in annual walking (minutes per week per year) for a 1-standard-deviation increase in the change in the built environment feature over time. Estimates were from models that were controlled for baseline built environment measures, changes in built environment, time (in years), baseline age, an interaction between baseline age and time, sex, race, an interaction between race and time, educational level, income, employment, marital status, car ownership, cancer, arthritis, body mass index, self-rated health compared with others, and site.