Daniel Rainham

Conceptualizing the healthscape: Contributions of time geography, location technologies and spatial ecology to place and health research

Geomatics and related technologies allow for the application of integrated approaches to the analysis of individual spatial and temporal activities in the context of place and health research. The ability to track individuals as they make decisions and negotiate space may provide a fundamental advance. This paper introduces the need to move beyond conventional place-based perspectives in health research, and invokes the theoretical contributions of time geography and spatial ecology as opportunities to integrate human agency into contextual models of health. Issues around the geographical representation of place are reviewed, and the concept of the healthscape is introduced as an approach to operationalizing context as expressed by the spatial and temporal activities of individuals. We also discuss how these concepts have the potential to influence and contribute to empirical place and health research.

Estimates of global mortality attributable to particulate air pollution using satellite imagery

BACKGROUND Epidemiological studies of the health effects of air pollution have traditionally relied upon ground-monitoring stations to measure ambient concentrations. Satellite derived air pollution measures offer the advantage of providing global coverage. OBJECTIVE To undertake a global assessment of mortality associated with long-term exposure to fine particulate air pollution using remote sensing data. METHODS Global PM(2.5) exposure levels were derived from the MODIS and MISR satellite instruments. Relative risks and attributable fractions of mortality were modeled using previously developed concentration-response functions for the association between PM(2.5) and mortality. RESULTS The global fraction of adult mortality attributable to the anthropogenic component of PM(2.5) (95% CI) was 8.0% (5.3-10.5) for cardiopulmonary disease, 12.8% (5.9-18.5) for lung cancer, and 9.4% (6.6-11.8) for ischemic heart disease. CONCLUSION This study demonstrates the feasibility of using satellite derived pollution concentrations in assessing the population health impacts of air pollution at the global scale. This approach leads to global estimates of mortality attributable to PM(2.5) that are greater than those based on fixed site ground-level measures of urban PM(2.5), but more similar to estimates based on global chemical transport model simulations of anthropogenic PM(2.5).

Spatial classification of youth physical activity patterns.

BACKGROUND Physical activity is an essential element in reducing the prevalence of obesity, but much is unknown about the intensity and location of physical activity among youth-this is important because adolescent health behaviors are predictive of behaviors in adults. PURPOSE This study aims to identify the locations where youth moderate-to-vigorous physical activity (MVPA) occurs, and to examine how MVPA varies according to urbanicity (urban, suburban, rural). METHODS Participants included adolescent students (N=380, aged 12-16 years) from Halifax, Nova Scotia. Locations of MVPA were measured using accelerometers and GPS data loggers for up to 7 days. Specialized software was developed to integrate and process the data. Frequencies of MVPA by location were determined, and differences in MVPA were assessed for association with urbanicity. RESULTS Active commuting accounted for the largest proportion of time in MVPA among urban and suburban students. Rural students achieved most MVPA at school. Other residential locations, shopping centers, and green spaces accounted for a majority of the remaining MVPA. Minutes in MVPA varied significantly overall (196.6 ± 163.8, 84.9 ± 103.2, 81.7 ± 98.2); at school (45.7 ± 45.2, 18.6 ± 28.0, 29.8 ± 39.7); while commuting (110.3 ± 107.1, 31.5 ± 55.2, 19.5 ± 39.7); and at other activity locations (19.7 ± 27.1, 14.8 ± 26.8, 12.0 ± 22.1) and by urbanicity. CONCLUSIONS Findings reveal that the journeys between locations are as important as home and school settings in contributing to greater MVPA in adolescent youth. The relative importance of context as a contributor to MVPA varies with urbanicity. Combining actimetry and GPS data provides a precise link between physical activity measurements and contexts of the built environment.

Noise Levels Associated with Urban Land Use

Recent trends towards the intensification of urban development to increase urban densities and avoid sprawl should be accompanied by research into the potential for related health impacts from environmental exposure. The objective of the current study was to examine the effect of the built environment and land use on levels of environmental noise. Two different study areas were selected using a combination of small area census geography, land use information, air photography, and ground-truthing. The first study area represented residential land use and consisted of two- to three-story single-family homes. The second study area was characteristic of mixed-use urban planning with apartment buildings as well as commercial and institutional development. Study areas were subdivided into six grids, and a location was randomly selected within each grid for noise monitoring. Each location was sampled four times over a 24-h day, resulting in a total of 24 samples for each of the two areas. Results showed significant variability in noise within study areas and significantly higher levels of environmental noise in the mixed-use area. Both study areas exceeded recommended noise limits when evaluated against World Health Organization guidelines and yielded average noise events values in the moderate to serious annoyance range with the potential to obscure normal conversation and cause sleep disturbance.

A small-area analysis of inequalities in chronic disease prevalence across urban and non-urban communities in the Province of Nova Scotia, Canada, 2007-2011.

Background Small-area studies of health inequalities often have an urban focus, and may be limited in their translatability to non-urban settings. Using small-area units representing communities, this study assessed the influence of living in different settlement types (urban, town and rural) on the prevalence of four chronic diseases (heart disease, cancer, diabetes and stroke) and compared the degrees of associations with individual-level and community-level factors among the settlement types. Methods The associations between community-level and individual-level characteristics and prevalence of the chronic diseases were assessed using logistic regression (multilevel and non-multilevel) models. Individual-level data were extracted from the Canadian Community Health Survey (2007–2011). Indices of material deprivation and social isolation and the settlement type classification were created using the Canadian Census. Results Respondents living in towns were 21% more likely to report one of the diseases than respondents living in urban communities even after accounting for individual-level and community-level characteristics. Having dependent children appeared to have protective effects in towns, especially for males (OR: 0.49 (95% CI 0.27 to 0.90)). Unemployment had a strong association for all types of communities, but being unemployed appeared to be particularly damaging to health of males in urban communities (OR: 2.48 (95% CI 1.43 to 4.30)). Conclusions The study showed that those living in non-urban settings, particularly towns, experience extra challenges in maintaining health above and beyond the socioeconomic condition and social isolation of the communities, and individual demographic, behavioural and socioeconomic attributes. Our findings also suggest that health inequality studies based on urban-only settings may underestimate the risks by some factors. Ways to devise meaningful small-area units comparable in all settlement types are necessary to help plan effective provision of chronic disease-related health services and programmes on a regional scale.

Examining the place of ecological integrity in environmental justice: A systematic review

Environmental justice research is predominately an anthropocentric endeavour, and it is unclear whether this research captures injustices to other species or the integrity of ecological systems that support all life on earth. The purpose of this article is three-fold. First, we systematically review the environmental justice literature to identify the epistemological perspectives from which environmental justice is conveyed. Second, we examine definitions of environmental justice to determine how the concept is operationalised across these paradigms. Third, we document under what conditions these definitions purposely acknowledge the interdependency of all species in order to elucidate the place (or absence) of ecological integrity in our understanding of environmental justice. We conclude with a discussion of the value of going beyond mainstream expressions of environmental justice that typically do not include ecological integrity as a way to begin addressing the problem in a more holistic way.

Risk factors predisposing to pedestrian road traffic injury in children living in Lima, Peru: a case–control study

Objective To describe the epidemiology of pedestrian road traffic injury in Lima and to identify associated child-level, family-level, and school travel-related variables. Design Case–control study. Setting The Instituto Nacional de Salud del Niño, the largest paediatric hospital in the city. Participants Cases were children who presented because of pedestrian road traffic injury. Controls presented with other diagnoses and were matched on age, sex and severity of injury. Results Low socioeconomic status, low paternal education, traffic exposure during the trip to school, lack of supervision during outside play, and duration of outside play were all statistically significantly associated with case–control status. In multivariate logistic regression, a model combining the lack of supervision during outside play and the number of the streets crossed walking to school best predicted case–control status (p<0.001). Conclusions These results emphasise that an assessment of childrens play behaviours and school locations should be considered and integrated into any plan for an intervention designed to reduce pedestrian road traffic injury. A child-centred approach will ensure that children derive maximum benefit from sorely needed public health interventions.

Maternal Exposure to Air Pollution and Adverse Birth Outcomes in Halifax, Nova Scotia.

Objective: We aimed to examine the associations between exposure to air pollution exposure and the outcomes of preterm birth (PTB), term low birth weight (TLBW), and small for gestational age. Methods: We conducted a population-based cohort study using a perinatal database linked to land-use regression-modeled air pollution data. Results: Compared with women in the lowest quartile of toluene exposure, those in the second lowest quartile showed a positive association with PTB (odds ratio = 1.35, 95% confidence interval: 1.12, 1.63). A piecewise logistic regression breakpoint analysis identified a cut point (identifying a change in the slope) of 0.36 &mgr;g/m3 for toluene and the risk of PTB. There was also some evidence to suggest an association between sulfur dioxide and TLBW. Conclusions: This study provides some evidence to suggest that in an area of relatively low air pollution concentration, maternal exposure to some air pollutants may be associated with adverse birth outcomes.

A systematic gender-based review of physical activity correlates in coronary heart disease patients

Coronary heart disease is the leading cause of death for Canadian men and women due largely to insufficient cardiovascular fitness gained via physical activity. Thus, health promotion efforts should be directed at increasing physical activity levels in both men and women living with heart disease. These efforts should be informed by research identifying the key correlates of physical activity that influence the uptake and long-term maintenance of physical activity among men and women with heart disease. The objective of this article was to provide a review of physical activity correlates in men and women with heart disease by sourcing information from eligible gender-based studies on physical activity and heart disease. The social ecological model was used to organise the physical activity correlates at the intrapersonal, interpersonal, institutional, community and policy levels. Despite certain methodological challenges and inconsistencies across studies, findings indicated that physical activity in men and women with heart disease is largely influenced by intrapersonal correlates. Specifically, physical activity in women with heart disease is more influenced by physical barriers, while physical activity in men with heart disease is more influenced by psychological issues and social support.

Factoring in weather variation to capture the influence of urban design and built environment on globally recommended levels of moderate to vigorous physical activity in children.

Objectives In curbing physical inactivity, as behavioural interventions directed at individuals have not produced a population-level change, an ecological perspective called active living research has gained prominence. However, active living research consistently underexplores the role played by a perennial phenomenon encompassing all other environmental exposures—variation in weather. After factoring in weather variation, this study investigated the influence of diverse environmental exposures (including urban design and built environment) on the accumulation of globally recommended moderate to vigorous physical activity levels (MVPA) in children. Design This cross-sectional observational study is part of an active living initiative set in the Canadian prairie city of Saskatoon. As part of this study, Saskatoons neighbourhoods were classified based on urban street design into grid-pattern, fractured grid-pattern and curvilinear types of neighbourhoods. Moreover, diverse environmental exposures were measured including, neighbourhood built environment, and neighbourhood and household socioeconomic environment. Actical accelerometers were deployed between April and June 2010 (spring-summer) to derive MVPA of 331 10–14-year-old children in 25 1-week cycles. Each cycle of accelerometry was conducted on a different cohort of children within the total sample and matched with weather data obtained from Environment Canada. Multilevel modelling using Hierarchical Linear and Non-linear Modelling software was conducted by factoring in weather variation to depict the influence of diverse environmental exposures on the accumulation of recommended MVPA. Results Urban design, including diversity of destinations within neighbourhoods played a significant role in the accumulation of MVPA. After factoring in weather variation, it was observed that children living in neighbourhoods closer to the city centre (with higher diversity of destinations) were more likely to accumulate recommended MVPA. Conclusions The findings indicate that after factoring in weather variation, certain types of urban design are more likely to be associated with MVPA accumulation.