In summary, these data from a large, multi-ethnic, population-based sample of Dallas County residents identify perceptions about neighborhood violence, physical environment, and social cohesion as psychosocial factors associated with neighborhood environment for Dallas County adults. Blacks and individuals of lower socioeconomic status reported less favorable perceptions of environment, particularly in relation to neighborhood violence and physical environment. To explore a possible mechanistic pathway between neighborhood characteristics and prevalent obesity, we examined the association between perceptions of neighborhood environment and prevalent obesity for Dallas County adults. In this population, unfavorable perceptions of the physical environment portend an increased likelihood of prevalent obesity; perceived aesthetics of the neighborhood environment and access to safe recreational areas appear to play a key role in this relationship. Thus, targeting physical conditions of neighborhoods in Dallas County may aid in preventing obesity for this population.
Our findings highlight several important issues. First, consistent with previous work, unfavorable perceptions of a neighborhood environment, particularly the physical environment of the neighborhood, are associated with obesity. In a prior study of individuals in two urban communities in the U.S., those who perceived a lack of sidewalks or poor aesthetics in their community were more than twice as likely to be obese as compared to those who perceived adequate sidewalks and aesthetics.19
The odds of prevalent obesity in relation to perceived lack of sidewalks was higher in this population (adjusted OR = 2.2, 95% CI = 1.1–4.3) compared to our present study; however, we additionally adjusted logistic regression models for potential confounders including race, family income, and reported length of residence in neighborhood, which may explain these differences. Moreover, our findings related to physical environment perception and prevalent obesity are similar in magnitude to results from a large, population-based sample of British adults (adjusted OR = 1.2, 95% CI = 1.0–1.3).18
Other work from the Multiethnic Study of Atherosclerosis (MESA) demonstrated that favorable physical environment characteristics, such as availability of walking paths and healthy foods, were associated with lower body mass index. However, this study used a community survey for non-MESA participants as a proxy measure of physical environment for the study population, thereby making it difficult to decipher how perceptions of the physical environment is related to obesity in this population.21
Second, our results demonstrate no significant association between perceptions about food store availability and prevalent obesity in the DHS population. In addition, there was little difference in reported physical activity with worsening perception of neighborhood environment. Intriguingly, these findings suggest that an ability to comply with beneficial health behaviors, like healthy eating and physical activity, may not mediate the relationship between perceptions about the neighborhood environment and obesity for Dallas County adults. Data from prior studies support these findings. For instance, Poortinga et al. showed that physical activity did not mediate the relationship between perceived access to recreation amenities in the local environment and obesity, suggesting other undefined mechanisms through which perceptions of environment may lead to obesity.18
The lack of a relationship between perceived food store access and obesity may also reflect variability in what stressors activate the biological pathways between psychosocial stress related to neighborhood environment and obesity.26
Emerging data suggest the possibility that differential neural mechanisms for processing acute stressors may be related to the environment in which an individual was raised or currently lives, a hypothesis that could reflect the aforementioned variability noted.27
Third, unlike other cardiovascular risk factors like hypertension and hyperlipidemia, obesity prevalence increased in the DHS population with less favorable perceptions of the neighborhood environment, suggesting that perceptions about one’s neighborhood may represent a unique pathway by which neighborhood characteristics are associated with cardiovascular risk. Perceptions may denote an individual’s psychological response to their neighborhood environment. At a macro-level, prior work supports psychological stress as a mediator of perceptions about neighborhood environment and obesity.17, 29
For instance, in a probability sample of over 1,500 Texas adults, Burdette and colleagues demonstrated an association between prevalent obesity and perceptions about crime, noise, and cleanliness in participants’ neighborhood environment. Perceptions of greater neighborhood disorder were associated with a greater odds of obesity, after accounting for age, sex, race, and SES in this population; however, the odds of obesity was reduced by 3% and no longer statistically significant when psychological distress, as measured by reported sensations of anxiety or restlessness, was added to the regression model.17
At a molecular level, individual-level SES, a potential surrogate for neighborhood deprivation, in childhood has been shown to influence release of stress-induced hormones such as cortisol and interleukin-6 (IL-6) that may promote obesity in adulthood.28
Recent data support a relationship between neighborhood-level characteristics, such as census-measured neighborhood disorder, neighborhood deprivation, or poorer neighborhood aesthetics and higher levels of cortisol or inflammatory biomarkers associated with obesity.14, 16
Future studies should explore the connection between perceptions of the neighborhood environment and specific stress-related biomarkers that promote obesity and thus, cardiovascular risk.
Fourth, in contrast to our findings, other studies have found associations between neighborhood violence and obesity. For instance, a random sample of adult Los Angeles residents who perceived their neighborhood as unsafe had significantly higher BMI than those who described their neighborhoods as safe.20
Built environment measures, such as walkability and street connectivity, and perceived overall safety or safety from crime have also been shown to have an independent association with lower BMI.30
Our findings might differ from some previous work due to differences in the racial/ethnic makeup and population sampling of our participants. Additionally, our study includes comprehensive measurement of perceptions about neighborhood environment in Dallas County which facilitated examination of relative associations between multiple facets of the neighborhood environment and prevalent obesity.
Important strengths of our study include the multi-ethnic, urban nature of the cohort, and measurement of height and weight as opposed to the use of self-reported measures to estimate BMI.17, 19–20
However, limitations of the present study must also be considered. These data are cross-sectional and, therefore, we cannot infer causality. We are also unable to evaluate the bi-directional relationship between one’s living environment and weight status. Healthier, more financially secure individuals may self-select neighborhoods they perceive as providing adequate resources for healthy foods and physical activity just as one’s neighborhood may impact perceptions about one’s environment, health beliefs, and behaviors.2
Additionally, physical activity was self-reported, making it subject to misclassification bias. Finally, given that the DHS represents an urban and geographically localized population in the U.S., findings may not be applicable to populations in other settings.
In conclusion, perceptions of neighborhood environment, particularly relative to the physical environment, are associated with an increased prevalence of obesity among Dallas County residents. Our results are hypothesis-generating and suggest that public policy efforts that focus on improvement of the county’s physical environment, or perceptions of that environment, might be an important element in reducing the obesity epidemic in this community. Also, specific research is needed that directly evaluates the potential interplay between neighborhood environment, psychosocial stress and health conditions. Since longitudinal evidence suggests that psychosocial stress is associated with obesity,31
identification of specific stressors related to the neighborhood may help in the development of targeted interventions to prevent and reduce obesity.