Geographic life environments and coronary heart disease: a literature review, theoretical contributions, methodological updates, and a research agenda

Feasibility of using global positioning systems (GPS) with diverse urban adults: before and after data on perceived acceptability, barriers, and ease of use

BACKGROUND

Global positioning systems (GPS) have emerged as a research tool to better understand environmental influences on physical activity. This study examined the feasibility of using GPS in terms of perceived acceptability, barriers, and ease of use in a racially/ethnically diverse sample of lower socioeconomic position (SEP).

METHODS

Data were from 2 pilot studies involving a total of 170 African American, Hispanic, and White urban adults with a mean (standard deviation) age of 47.8 (±13.1) years. Participants wore a GPS for up to 7 days. They answered questions about GPS acceptability, barriers (wear-related concerns), and ease of use before and after wearing the GPS.

RESULTS

We found high ratings of GPS acceptability and ease of use and low levels of wear-related concerns, which were maintained after data collection. While most were comfortable with their movements being tracked, older participants (P < .05) and African Americans (P < .05) reported lower comfort levels. Participants who were younger, with higher education, and low incomes were more likely to indicate that the GPS made the study more interesting (P < .05). Participants described technical and wear-related problems, but few concerns related to safety, loss, or appearance.

CONCLUSIONS

Use of GPS was feasible in this racially/ethnically diverse, lower SEP sample.

Place effects for areas defined by administrative boundaries: a life course analysis of mortality and cause specific morbidity in Scania, Sweden

To understand the origin of disease risk in adulthood, factors in all stages of life and on different contextual levels should be considered. Therefore, the aim of this study was to investigate the relevance of a person's area of residence over their life course with regard to four outcomes: all-cause mortality; ischemic heart disease mortality and morbidity; cancer mortality and morbidity; and respiratory diseases and related mortality. We applied a cross-classified multilevel model for three age groups on a longitudinal data set spanning a 35 year period in Scania, Sweden. According to our analyses, the proportion of the total variance at the district level for all the outcomes studied was below 2% for the 65 to 84 age group, below 4.5% for those ages 50-64 years, and below 6.5% for those 30-49 years old. Our results suggest that the parish of residence, at four different time points during the individual life course, had little influence on individual all-cause mortality, or on mortality or morbidity from IHD, cancer, and respiratory diseases; i.e., knowing when and where an individual resided during their life course gives little indication of future mortality and morbidity. Such knowledge is essential in assisting decision makers determine the relevant geographical level of intervention (in our case whether to direct interventions toward the entire region of Scania or to specific parishes) needed. Valuable information for planning public health interventions might be obtained by considering measures of variance and clustering from specific contexts before implementing strategic programs.

Environmental risk conditions and pathways to cardiometabolic diseases in indigenous populations

This review examines environments in relation to cardiometabolic diseases in Indigenous populations in developed countries. Environmental factors are framed in terms of context (features of places) and composition (features of populations). Indigenous peoples are seen to have endured sociopolitical marginalization and material disadvantage spanning generations. Past adverse collective experiences, modified by culture, are reflected by current heterogeneity in environmental context and composition. As risk conditions, unfavorable contextual and compositional exposures influence the expression of cardiometabolic risk for individuals. Minimal research has evaluated heterogeneity in risk conditions against heterogeneity in cardiometabolic diseases between or within Indigenous populations. Thus far, the features of populations, not of places themselves, have been implicated in relation to cardiometabolic diseases. Behavioral, psychosocial, and stress-axis pathways may explain the relationships between risk conditions and cardiometabolic diseases. Implications of environmental factors and their pathways as well as important research needs are discussed in relation to ecological prevention to reduce cardiometabolic diseases.

Neighborhood effects on health: correcting bias from neighborhood effects on participation

BACKGROUND

Studies of neighborhood effects on health that are based on cohort data are subject to bias induced by neighborhood-related selective study participation.

METHODS

We used data from the RECORD Cohort Study (REsidential Environment and CORonary heart Disease) carried out in the Paris metropolitan area, France (n = 7233). We performed separate and joint modeling of neighborhood determinants of study participation and type-2 diabetes. We sought to identify selective participation related to neighborhood, and account for any biasing effect on the associations with diabetes.

RESULTS

After controlling for individual characteristics, study participation was higher for people residing close to the health centers and in neighborhoods with high income, high property values, high proportion of the population looking for work, and low built surface and low building height (contextual effects adjusted for each other). After individual-level adjustment, the prevalence of diabetes was elevated in neighborhoods with the lowest levels of educational attainment (prevalence odds ratio = 1.56 [95% credible interval = 1.06-2.31]). Neighborhood effects on participation did not bias the association between neighborhood education and diabetes. However, residual geographic variations in participation weakly biased the neighborhood education-diabetes association. Bias correction through the joint modeling of neighborhood determinants of participation and diabetes resulted in an 18% decrease in the log prevalence odds ratio for low versus high neighborhood education.

CONCLUSIONS

Researchers should develop a comprehensive, theory-based model of neighborhood determinants of participation in their study, investigate resulting biases for the environment-health associations, and check that unexplained geographic variations in participation do not bias these environment-health relationships.

The influence of geographic life environments on cardiometabolic risk factors: a systematic review, a methodological assessment and a research agenda

Recent environmental changes play a role in the dramatic increase in the prevalence of cardiometabolic risk factors (CMRFs) such as obesity, hypertension, type 2 diabetes, dyslipidemias and the metabolic syndrome in industrialized countries. Therefore, identifying environmental characteristics that are associated with risk factors is critical to develop more effective public health interventions. We conducted a systematic review of the literature investigating relationships between characteristics of geographic life environments and CMRFs (131 articles). Most studies were published after 2006, relied on cross-sectional designs, and examined whether sociodemographic and physical environmental characteristics, and more recently service environment characteristics, were associated with obesity or, to a lesser extent, hypertension. Only 14 longitudinal studies were retrieved; diabetes, dyslipidemias and the metabolic syndrome were rarely analysed; and aspects of social interactions in the neighbourhood were critically underinvestigated. Environmental characteristics that were consistently associated with either obesity or hypertension include low area socioeconomic position; low urbanization degree; low street intersection, service availability and residential density; high noise pollution; low accessibility to supermarkets and high density of convenience stores; and low social cohesion. Intermediate mechanisms between environmental characteristics and CMRFs have received little attention. We propose a research agenda based on the assessment of underinvestigated areas of research and methodological limitations of current literature.

Modelling the variation of land surface temperature as determinant of risk of heat-related health events

Background

The evaluation of exposure to ambient temperatures in epidemiological studies has generally been based on records from meteorological stations which may not adequately represent local temperature variability. Here we propose a spatially explicit model to estimate local exposure to temperatures of large populations under various meteorological conditions based on satellite and meteorological data.

Methods

A general linear model was used to estimate surface temperatures using 15 LANDSAT 5 and LANDSAT 7 images for Quebec Province, Canada between 1987 and 2002 and spanning the months of June to August. The images encompassed both rural and urban landscapes and predictors included: meteorological records of temperature and wind speed, distance to major water bodies, Normalized Differential Vegetation Index (NDVI), land cover (built and bare land, water, or vegetation), latitude, longitude, and week of the year.

Results

The model explained 77% of the variance in surface temperature, accounting for both temporal and spatial variations. The standard error of estimates was 1.42°C. Land cover and NDVI were strong predictors of surface temperature.

Conclusions

This study suggests that a statistical approach to estimating surface temperature incorporating both spatially explicit satellite data and time-varying meteorological data may be relevant to assessing exposure to heat during the warm season in the Quebec. By allowing the estimation of space- and time-specific surface temperatures, this model may also be used to assess the possible impacts of land use changes under various meteorological conditions. It can be applied to assess heat exposure within a large population and at relatively fine-grained scale. It may be used to evaluate the acute health effect of heat exposure over long time frames. The method proposed here could be replicated in other areas around the globe for which satellite data and meteorological data is available.

Estimating spatial accessibility to facilities on the regional scale: an extended commuting-based interaction potential model

Background

There is growing interest in the study of the relationships between individual health-related behaviours (e.g. food intake and physical activity) and measurements of spatial accessibility to the associated facilities (e.g. food outlets and sport facilities). The aim of this study is to propose measurements of spatial accessibility to facilities on the regional scale, using aggregated data. We first used a potential accessibility model that partly makes it possible to overcome the limitations of the most frequently used indices such as the count of opportunities within a given neighbourhood. We then propose an extended model in order to take into account both home and work-based accessibility for a commuting population.

Results

Potential accessibility estimation provides a very different picture of the accessibility levels experienced by the population than the more classical "number of opportunities per census tract" index. The extended model for commuters increases the overall accessibility levels but this increase differs according to the urbanisation level. Strongest increases are observed in some rural municipalities with initial low accessibility levels. Distance to major urban poles seems to play an essential role.

Conclusions

Accessibility is a multi-dimensional concept that should integrate some aspects of travel behaviour. Our work supports the evidence that the choice of appropriate accessibility indices including both residential and non-residential environmental features is necessary. Such models have potential implications for providing relevant information to policy-makers in the field of public health.

Do the wealthy have a health advantage? Cardiovascular disease risk factors and wealth

The use of wealth as a measure of socioeconomic status (SES) remains uncommon in epidemiological studies. When used, wealth is often measured crudely and at a single point in time. Our study explores the relationship between wealth and three cardiovascular disease (CVD) risk factors (smoking, obesity and hypertension) in a US population. We improve upon existing literature by using a detailed and validated measure of wealth in a longitudinal setting. We used four waves of data from the Panel Study of Income Dynamics (PSID) collected between 1999 and 2005. Inverse probability weights were employed to control for time-varying confounding and to estimate both relative (risk ratio) and absolute (risk difference) measures of effect. Wealth was defined as inflation-adjusted net worth and specified as a six category variable: one category for those with less than or equal to zero wealth and quintiles of positive wealth. After adjusting for income and other time-varying confounders, as well as baseline covariates, the risk of becoming obese was inversely related to wealth. There was a 40%-89% higher risk of becoming obese among the less wealthy relative to the wealthiest quintile and 11 to 25 excess cases (per 1000 persons) among the less wealthy groups over six years of follow up. Smoking initiation had similar but more moderate effects; risk ratios and differences both revealed a smaller magnitude of effect compared to obesity. Of the three CVD risk factors examined here, hypertension incidence had the weakest association with wealth, showing a smaller increased risk and fewer excess cases among the less wealthy groups. In conclusion, this study found a strong inverse association between wealth and obesity incidence, a moderate inverse association between wealth and smoking initiation and a weak inverse association between wealth and hypertension incidence after controlling for income and other time-varying confounders.

Replication of the neighborhood active living potential measure in Saskatoon, Canada

BACKGROUND

Few neighborhood observational measures have been replicated by separate research teams in different cities.

PURPOSE

This study replicates the neighborhood active living potential observation measure in Saskatoon, Saskatchewan, Canada.

METHODS

Observers (n=5) participated in a 3-day neighborhood active living potential training session. Observers rated 60 neighborhoods in Saskatoon during the summer of 2009 by following a predetermined walking route constructed by joining ten randomly selected street segments for each neighborhood. Pairs of observers independently rated neighborhoods using an 18-item observation grid. Items represented three a priori-defined domains of active living potential: activity friendliness (six items); safety (four items); and density of destinations (eight items). Data analysis was conducted in autumn 2009.

RESULTS

Application of ecometric multilevel modeling analyses showed that once inter-item and inter-observer variability were statistically controlled, one third of the variability in observations was among neighborhoods. Reliability estimates for observers were 0.84 for items measuring activity friendliness, 0.82 for safety, and 0.91 for density of destinations. Convergent validity showed that neighborhood income was associated negatively with density of destinations, positively with safety, and not associated with activity friendliness. Percentage of people in the neighborhood walking to work was positively associated with density of destinations and not associated with safety or activity friendliness.

CONCLUSIONS

Results replicate findings from Montreal, Canada, that the three dimensions of the neighborhood active living potential measure have good reliability and convergent validity. Neighborhood active living potential appears to be a stable measure capturing three essential elements of neighborhoods.

Neighborhood disadvantage and physical activity: baseline results from the HABITAT multilevel longitudinal study

PURPOSE

To examine the association between neighborhood disadvantage and physical activity (PA).

METHODS

We use data from the HABITAT multilevel longitudinal study of PA among middle-aged (40-65 years) men and women (N = 11,037, 68.5% response rate) living in 200 neighborhoods in Brisbane, Australia. PA was measured using three questions from the Active Australia Survey (general walking, moderate, and vigorous activity), one indicator of total activity, and two questions about walking and cycling for transport. The PA measures were operationalized by using multiple categories based on time and estimated energy expenditure that were interpretable with reference to the latest PA recommendations. The association between neighborhood disadvantage and PA was examined with the use of multilevel multinomial logistic regression and Markov chain Monte Carlo simulation. The contribution of neighborhood disadvantage to between-neighborhood variation in PA was assessed using the 80% interval odds ratio.

RESULTS

After adjustment for sex, age, living arrangement, education, occupation, and household income, reported participation in all measures and levels of PA varied significantly across Brisbane's neighborhoods, and neighborhood disadvantage accounted for some of this variation. Residents of advantaged neighborhoods reported significantly higher levels of total activity, general walking, moderate, and vigorous activity; however, they were less likely to walk for transport. There was no statistically significant association between neighborhood disadvantage and cycling for transport. In terms of total PA, residents of advantaged neighborhoods were more likely to exceed PA recommendations.

CONCLUSIONS

Neighborhoods may exert a contextual effect on the likelihood of residents participating in PA. The greater propensity of residents in advantaged neighborhoods to do high levels of total PA may contribute to lower rates of cardiovascular disease and obesity in these areas.

Individual/neighborhood social factors and blood pressure in the RECORD Cohort Study: which risk factors explain the associations?

Recent studies have started to suggest that, beyond effects of individual socioeconomic profiles, socioeconomic characteristics of residential neighborhoods are independently associated with blood pressure. However, mechanisms involved in these associations remain unknown. To distinguish between different mechanisms, we investigated whether specific risk factors of hypertension (physical inactivity, alcohol consumption, smoking, body mass index, waist circumference, and resting heart rate) intervene as mediators in the associations between individual or neighborhood socioeconomic characteristics and systolic blood pressure. We relied on data from the RECORD Cohort Study (Residential Environment and CORonary heart Disease) on 5941 participants recruited in 2007-2008, aged 30 to 79 years, residing in 1824 neighborhoods in the Paris metropolitan area. Systolic blood pressure increased independently and regularly with both decreasing individual education and decreasing residential neighborhood education. Body mass index/waist circumference and resting heart rate mediated an appreciable share of the associations between education and blood pressure and, adding validity to the finding, were the 2 most significant mediators for the effects of both individual education and neighborhood education. We found that 52% (95% CI: 25% to 79%) of the association between neighborhood education and blood pressure was mediated by body mass index/waist circumference and 20% (95% CI: 5% to 36%) by resting heart rate. Future research will have to clarify the exact mechanisms through which body weight and shape and resting heart rate intervene as mediators in the associations between individual/neighborhood education and blood pressure.

Investigating the spatial variability in incidence of coronary heart disease in the Gazel cohort: the impact of area socioeconomic position and mediating role of risk factors

STUDY OBJECTIVE

The aim of the study was to improve understanding of the relationships between contextual socioeconomic characteristics and coronary heart disease (CHD) incidence in France. Several authors have suggested that CHD risk factors (diabetes, hypertension, cholesterol, overweight, tobacco consumption) may partly mediate associations between socioeconomic environmental variables and CHD. Studies have assessed the overall mediating role of CHD risk factors, but have never investigated the specific mediating role of each risk factor, not allowing their specific contribution to the area socioeconomic position-CHD association to be disentangled.

DESIGN

After assessing geographical variations in CHD incidence and socioeconomic environmental effects on CHD using a multilevel Cox model, the extent to which this contextual effect was mediated by each of the CHD risk factors was assessed.

PARTICIPANTS

Data of the French GAZEL cohort (n=19,808) were used.

MAIN RESULTS

After adjustment for several individual socioeconomic indicators, it was found, in men from highly urbanised environments, that CHD incidence increased with decreasing socioeconomic position of the residential environment. After individual-level adjustment, a higher risk of obesity, smoking and cholesterol was observed in the most deprived residential environments. When risk factors were introduced into the model, a modest decrease was observed in the magnitude of the association between the socioeconomic contextual variable and CHD. Risk factors that contributed most to the decrease of the association were smoking and cholesterol.

CONCLUSIONS

Classic risk factors, although some of them more than others, mediated a modest part of the association between area socioeconomic position and CHD.

Is segregation bad for your health?

For decades, racial residential segregation has been observed to vary with health outcomes for African Americans, although only recently has interest increased in the public health literature. Utilizing a systematic review of the health and social science literature, the authors consider the segregation-health association through the lens of 4 questions of interest to epidemiologists: How is segregation best measured? Is the segregation-health association socially or biologically plausible? What evidence is there of segregation-health associations? Is segregation a modifiable risk factor? Thirty-nine identified studies test an association between segregation and health outcomes. The health effects of segregation are relatively consistent, but complex. Isolation segregation is associated with poor pregnancy outcomes and increased mortality for blacks, but several studies report health-protective effects of living in clustered black neighborhoods net of social and economic isolation. The majority of reviewed studies are cross-sectional and use coarse measures of segregation. Future work should extend recent developments in measuring and conceptualizing segregation in a multilevel framework, build upon the findings and challenges in the neighborhood-effects literature, and utilize longitudinal data sources to illuminate opportunities for public health action to reduce racial disparities in disease.