Association between activity space exposure to food establishments and individual risk of overweight.

OBJECTIVE: Environmental exposure to food sources may underpin area level differences in individual risk for overweight. Place of residence is generally used to assess neighbourhood exposure. Yet, because people are mobile, multiple exposures should be accounted for to assess the relation between food environments and overweight. Unfortunately, mobility data is often missing from health surveys. We hereby test the feasibility of linking travel survey data with food listings to derive food store exposure predictors of overweight among health survey participants. METHODS: Food environment exposure measures accounting for non-residential activity places (activity spaces) were computed and modelled in Montreal and Quebec City, Canada, using travel surveys and food store listings. Models were then used to predict activity space food exposures for 5,578 participants of the Canadian Community Health Survey. These food exposure estimates, accounting for daily mobility, were used to model self-reported overweight in a multilevel framework. Median Odd Ratios were used to assess the proportion of between-neighborhood variance explained by such food exposure predictors. RESULTS: Estimates of food environment exposure accounting for both residential and non-residential destinations were significantly and more strongly associated with overweight than residential-only measures of exposure for men. For women, residential exposures were more strongly associated with overweight than non-residential exposures. In Montreal, adjusted models showed men in the highest quartile of exposure to food stores were at lesser risk of being overweight considering exposure to restaurants (OR = 0.36 [0.21-0.62]), fast food outlets (0.48 [0.30-0.79]), or corner stores (0.52 [0.35-0.78]). Conversely, men experiencing the highest proportion of restaurants being fast-food outlets were at higher risk of being overweight (2.07 [1.25-3.42]). Women experiencing higher residential exposures were at lower risk of overweight. CONCLUSION: Using residential neighbourhood food exposure measures may underestimate true exposure and observed associations. Using mobility data offers potential for deriving activity space exposure estimates in epidemiological models.

Local context influence, activity space, and foodscape exposure in two canadian metropolitan settings: is daily mobility exposure associated with overweight?

It has become increasingly common to attribute part of the obesity epidemic to changes in the environment. Identification of a clear and obvious role for contextual risk factors has not yet been demonstrated. The objectives of this study were to explain differences in local overweight risk in two different urban settings and to explore sex-specific associations with estimated mobility patterns. Overweight was modeled within a multilevel framework using built environmental and socioeconomic contextual indicators and individual-level estimates of activity space exposure to fast-food restaurants (or exposure to visited places). Significant variations in local levels in overweight risk were observed. Physical and socioeconomic contexts explained more area-level differences in overweight among men than among women and among inhabitants of Montreal than among inhabitants of Quebec City. Estimated activity space exposure to fast-food outlets was significantly associated with overweight for men in Montreal. Local-level analyses are required to improve our understanding of contextual influences on obesity, including multiple influences in people's daily geographies.

Concept mapping of diet and physical activity: uncovering local stakeholders perception in the Quebec City region.

Overweight and obesity are major public health concerns that are neither evenly distributed among the population nor between regions. Many studies suggest that beyond individual characteristics, the place where one lives influences lifestyle choices that underpin overweight and obesity. We observed such a situation in the province of Quebec (Canada), and because data availability from surveys was limited to a local level, the observed overweight disparities between local communities could not be entirely explained. Aiming to uncover local factors not captured by national survey data sets and in order to aid local level intervention, we investigated how the overweight problem was perceived by stakeholders through a concept mapping methodology. Concept mapping is a mixed method that relies upon stakeholders' perception as well as statistical techniques to draw a synthesis of the problem in the form of a conceptual map. A total of 45 stakeholders working in four areas with contrasting overweight prevalence in the Quebec City region were involved in the process. The map enables a global understanding of stakeholders' perception. This perception is not necessarily in line with public health knowledge however. For example, key concepts on the map suggest that physical activity is perceived to be much more important than diet with regards to population overweight and that urban design elements seem to be of low concern. Concept mapping is an innovative tool for planning and evaluation and can help stakeholders to develop adapted interventions to promote healthy lifestyle. It also provides relevant information to enhance the comprehension of local health disparities with a geographical perspective where data availability is limited.

Using experienced activity spaces to measure foodscape exposure.

Researchers are increasingly interested in understanding how food environments influence eating behavior and weight-related health outcomes. Little is known about the dose-response relationship between foodscapes and behavior or weight, with measures of food exposure having mainly focused on fixed anchor points including residential neighborhoods, schools, or workplaces. Recent calls have been made to extend the consideration of environmental influences beyond local neighborhoods and also to shift away from place-based, to people-based, measures of exposure. This report presents analyses of novel activity-space measures of exposure to foodscapes, combining travel survey data with food store locations in Montreal and Quebec City, Canada. The resulting individual activity-space experienced foodscape exposure measures differ from traditional residential-based measures, and show variations by age and income levels. Furthermore, these activity-space exposure measures once modeled, can be used as predictors of health outcomes. Hence, travel surveys can be used to estimate environmental exposure for health survey participants.

The geography of overweight in Quebec: analyzing and visualizing spatial inequalities using second-level residuals.

OBJECTIVE: To discuss critically the contribution of using second-level residuals from multilevel analyses to further the understanding of how place relates to health and to visualize areas, in the province of Quebec (Canada), with above- and below-average levels of overweight. METHODS: Data on 20,449 individuals are from the Canadian Community Health Survey (CCHS Cycle 2.1) and were linked to 51 spatial units. Area-level residuals were computed from a multilevel analysis examining individual and area characteristics associated with the risk of overweight. Mapping the area-level residuals indicates geographic areas where the risk of overweight is higher or lower compared to the provincial adjusted prevalence. RESULTS: Controlling for socio-economic conditions and lifestyle, distinct spatial patterns of overweight were observed, indicating that the processes linking place to health may differ between men and women and between regional contexts. In some regions, the probability of overweight differed by 23% for men and 38% for women living in privileged conditions in comparison to the province's adjusted prevalence of overweight. CONCLUSIONS: Analyzing and visualizing area-level residuals provides multi-scaled information that could enhance the understanding of the geographic distribution of overweight and has the potential to support more integrated and locally relevant interventions.

The geography of overweight in Quebec: a multilevel perspective.

OBJECTIVES: Explore the contextual aspects of overweight in Quebec through multilevel modelling, using a purposely designed set of spatial units and a few area-based characteristics. METHODS: Data came from the Canadian Community Health Survey (CCHS Cycle 2.1). Multilevel logistic regressions were performed to test for the presence of an independent contextual effect on overweight and obesity (BMI > or = 25 kg/m2), separately for men and women. Modelling considered individual attributes, including some lifestyle aspects, and contextual characteristics. A geographic grid integrating spatial elements related to overweight and obesity in the literature was developed. Also, an area-level residuals analysis was carried out to identify spatial units presenting higher or lower odds of being overweight. RESULTS: After accounting for individual and area-level characteristics, there remain significant geographic variations in overweight in Quebec. Although this contextual effect is small for men and women, many spatial units differ significantly from the provincial average. There are differences between the geography of overweight in men and women which suggest that socio-economic mechanisms and land use patterns underlying overweight might be different between genders. Also, there is considerable variability within rural and urban areas. CONCLUSION: A complex geography of overweight is revealed. Small-scale studies, as well as methodological and data developments, are needed to deepen our understanding of this geography.

Perception of drinking water in the Quebec City region (Canada): the influence of water quality and consumer location in the distribution system.

The purpose of every water utility is to provide consumers with drinking water that is aesthetically acceptable and presents no risk to public health. Several studies have been carried out to analyze people's perception and attitude about the drinking water coming from their water distribution systems. The goal of the present study is to investigate the influence of water quality and the geographic location of consumers within a distribution system on consumer perception of tap water. The study is based on the data obtained from two surveys carried out in municipalities of the Quebec City area (Canada). Three perception variables were used to study consumer perception: general satisfaction, taste satisfaction and risk perception. Data analysis based on logistic regression indicates that water quality variations and geographic location in the distribution system have a significant impact on the consumer perception. This impact appears to be strongly associated with residual chlorine levels. The study also confirms the importance of socio-economic characteristics of consumers on their perception of drinking water quality.