Associations between the traditional and novel neighbourhood built environment metrics and weight status among Canadian men and women

OBJECTIVES

Neighbourhood characteristics can impact the health of residents. This study investigated associations between objectively derived neighbourhood characteristics, including novel space syntax metrics, and self-reported body mass index (BMI) among Canadian men and women.

METHODS

Our study included survey data collected from a random cross-section of adults residing in Calgary, Alberta (n = 1718). The survey, conducted in 2007/2008, captured participants' socio-demographic characteristics, health, and weight status (BMI). Participants' household postal codes were geocoded and 1600-m line-based network buffers estimated. Using a geographical information system, we estimated neighbourhood characteristics within each buffer including business destination density, street intersection density, sidewalk length, and population density. Using space syntax, we estimated street integration and walkability (street integration plus population density) within each buffer. Using adjusted regression models, we estimated associations between neighbourhood characteristics and BMI (continuous) and BMI categories (healthy weight vs. overweight including obese). Gender-stratified analysis was also performed.

RESULTS

Business destination density was negatively associated with BMI and the odds of being overweight. Among men, street intersection density and sidewalk length were negatively associated with BMI and street intersection density, business destination density, street integration, and space syntax walkability were negatively associated with odds of being overweight. Among women, business destination density was negatively associated with BMI.

CONCLUSION

Urban planning policies that impact neighbourhood design have the potential to influence weight among adults living in urban Canadian settings. Some characteristics may have a differential association with weight among men and women and should be considered in urban planning and in neighbourhood-focussed public health interventions.

Associations between the neighbourhood characteristics and body mass index, waist circumference, and waist-to-hip ratio: Findings from Alberta's Tomorrow Project

This study estimated the associations between neighbourhood characteristics and self-reported body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) risk categories among Canadian men and women. Using data from the Alberta's Tomorrow Project (n = 14,550), we estimated 3- and 4-way intersections, business destinations, population count, and normalized difference vegetation index (NDVI) within a 400 m radius of participant's home. Intersections, business destinations, and population count (z-scores) were summed to create a walkability score. Four-way intersections and walkability were negatively associated with overweight and obesity. Walkability was negatively associated with obesity. NDVI was negatively associated with high-risk WHR and population count and walkability positively associated with high-risk WHR. Among men, population count and walkability were negatively associated with obesity, and business destinations and walkability were negatively associated with overweight and obesity. Among women, NDVI was negatively associated with overweight (including obesity), obesity, and high-risk WC. Interventions promoting healthy weight could incorporate strategies that take into consideration local built environment characteristics.

A population-based study of the associations between neighbourhood walkability and different types of physical activity in Canadian men and women

Few Canadian studies have examined whether or not associations between neighbourhood walkability and physical activity differ by sex. We estimated associations between perceived neighbourhood walkability and physical activity among Canadian men and women. This study included cross-sectional survey data from participants in 'Alberta's Tomorrow Project' (Canada; n = 14,078), a longitudinal cohort study. The survey included socio-demographic items as well as the International Physical Activity Questionnaire (IPAQ) and the abbreviated Neighbourhood Environment Walkability Scale (NEWS-A), which captured perceived neighbourhood built characteristics. We computed subscale and overall walkability scores from NEWS-A responses. Covariate-adjusted generalized linear models estimated the associations of participation (≥10 min/week) and minutes of different types of physical activity, including transportation walking (TW), leisure walking (LW), moderate-intensity physical activity (MPA), and vigorous-intensity physical activity (VPA) with walkability scores. Walkability was positively associated with participation in TW, LW, MPA and VPA and minutes of TW, LW, and VPA. Among men, a negative association was found between street connectivity and VPA participation. Additionally, crime safety was negatively associated with VPA minutes among men. Among women, pedestrian infrastructure was positively associated with LW participation and overall walkability was positively associated with VPA minutes. Notably, overall walkability was positively associated with LW participation among men and women. Different perceived neighbourhood walkability characteristics might be associated with participation and time spent in different types of physical activity among men and women living in Alberta. Interventions designed to modify perceptions of neighbourhood walkability might influence initiation or maintenance of different types of physical activity.

Green Space and Depression during Pregnancy: Results from the Growing Up in New Zealand Study

Background: Antenatal depression is an important contributor to poor maternal health experienced by some women. This study aimed to determine whether exposure to green space during pregnancy is associated with less depression, and whether this association is moderated by relevant factors, such as age, education, self-identified ethnicity, physical activity, residential rurality, and socioeconomic status. Methods: Health data were sourced from the cohort study “Growing Up in New Zealand” comprised of 6772 participants. Green space was estimated based on the proportion of green space within the Census Area Unit. Adjusted logistic mixed effect models were used to investigate the association between green space and antenatal depression after controlling for confounding variables. Results: Maternal exposure to green space were not associated with lower odds of antenatal depression. Indications of effect modifications due to relevant factors were not observed. Conclusions: This study did not determine an association between access to green space (measured based on the distance to the nearest green space) and antenatal depression. Therefore, a link between green space and antenatal depression was not established. For that reason, ensuring residential areas contain adequate green space may or may not be helpful in preventing antenatal depression and adverse health outcomes associated with this depression. More studies focusing on pregnant women in a range of social contexts, and considering both exposure and access to green space, are warranted to determine the relationships between green space and antenatal depression.

Green space and pregnancy outcomes: Evidence from Growing Up in New Zealand

OBJECTIVES

To determine whether maternal exposure to green space during pregnancy is associated with birth weight and gestational age, and whether these associations are modified by demographic and residential factors.

METHODS

Data describing 5091 mother-newborn pairs with residential address during pregnancy linked to data describing their green space exposure. Independent associations determined using linear mixed effects models.

RESULTS

Maternal exposure to green space during pregnancy was not associated with birth weight and gestational age for the entire cohort. For pregnant women who have not acquired secondary school education, increased exposure to green space was associated with increased gestational age.

CONCLUSION

The provision of green space might prove to be beneficial in terms of increasing gestational age for pregnant women who have not acquired secondary school education qualifications.

Blood lead levels in children after phase-out of leaded gasoline in Bombay, India

The objective of this study was to test for reduction in pediatric blood lead levels (BLLs) in Bombay, India, by comparing BLLs collected in 2002 (after use of leaded gasoline was phased out in Bombay) to those collected in a study conducted by the George Foundation in 1997 (when leaded gasoline was still used in Bombay). We analyzed BLL in a total of 754 children under 12 years of age in two separate sampling campaigns (276 from December 2002 to January 2003 [non-monsoon season]; 478 in June to August 2003 [monsoon season]). BLL was measured using an ESA Lead Care Portable Analyzer. We also measured lead in PM10 samples collected in the study region. These data were compared with a study done by the George Foundation in 1997 before the phase out of leaded gasoline. The George Foundation study reported that 61.8% of the 291 children tested in Bombay had elevated blood lead levels (BLL>or=10 microg/dL). In the present study, 33.2% of the 754 tested children had elevated blood lead levels. The average BLL for the current study population (Geometric Mean=8.36 microg/dL, SD=5.23 microg/dL) was lower than the CDC level of concern (10 microg/dL), with one child diagnosed with lead poisoning (BLL>65 microg/dL). A seasonal trend of BLLs was suggested, with BLL in monsoon season (Geometric Mean=9.1 microg/dL, SD=5.7 microg/dL) higher than that in the non-monsoon season (Geometric Mean=7.3 microg/dL, SD=4.0 microg/dL). A seasonal periodicity of lead in PM10 was found, with lead in monsoon season (Geometric Mean=0.04 microg/m3, SEM=0.000667 microg/m3) lower than that in the non-monsoon season (Geometric Mean=0.38 microg/m3, SEM=0.10 microg/m3). The overall level of airborne dust (PM10) in monsoon season (56.2 microg/m3) was lower than in the non-monsoon season (273.0 microg/m3), presumably due to precipitation. The comparatively higher BLLs in the monsoon season, in the presence of lower air lead levels, suggest ingestion of water or food, with greater lead contamination in the monsoon season, as a possible pathway contributing to elevated BLLs in these children in the monsoon season. These results demonstrate a significant success of the public health system in Bombay, India-achieved by the removal of lead from gasoline. The emphasis should shift in the study region towards sources of lead exposure other than leaded gasoline (lead in paints, lead in Herbal medicines and lead in Kohl).