McQueen, Matthew (McMaster University) and Lear, Scott (Simon Fraser University)
Chow, Clara (McMaster University); Dehghan, Mahshid (McMaster University); Pogue, Janice (McMaster University); Teo, Koon (McMaster University); Vaz, Mario (Bangalore University, India); Yusuf, Salim (McMaster University).
Cardiovascular disease (CVD) is the leading cause of death in Canada and the world. While CVD mortality rates have been declining in the developed countries, CVD mortality continues to rise in developing countries, where 80% of the world’s CVD deaths occur. This increase in developing countries is believed to be attributed to the increasing urbanization of these countries. Studies have indicated that the environment in which we live (such as the presence of sidewalks, green spaces, fast food restaurants, food availability and price, community advertisements), often referred to as the "built environment", is associated with behaviours related to CVD risk such as physical activity, nutrition and tobacco use. However, it is unknown whether these environmental factors, which are associated with behaviours, are in fact associated with CVD risk. Further, these studies have been limited to a small number of communities, predominantly in the United States, with very limited research conducted in Canada and in developing countries. Both the recent Canadian Heart Health Strategy and Action Plan and WHO’s Action Plan for the Global Strategy for the Prevention and Control of Non-communicable Diseases recognize that environmental factors can influence healthy lifestyles and “create” populations who are at low CVD risk. However, as a first step to achieving this, it is essential to identify the environmental factors associated with increased CVD risk.
We propose to identify the environmental determinants (from both the social and physical environment) of CVD risk in 52,800 men and women from 440 urban and rural communities across 17 countries worldwide. In this proposal, multiple levels of data already collected will be used to investigate the associations between environmental determinants (for example, opportunities for physical activity; availability, advertising and price of food, and availability and pricing of tobacco) and lipids (to be measured, for which this proposal requests funding) in urban and rural communities. As an indicator of CVD risk, we will be assessing individual fasting total cholesterol, LDL-C, HDL-C and triglyceride levels.
The specific aims of this investigation are:
1. To identify the association between perceived and objective environmental factors and lipid levels across 440 urban and rural communities in 17 countires.
2. To determine whether the country level gross national income per capita influences the relationship between the perceived and objective environmental measures and lipids.
Our proposal will address the current gaps in knowledge (including the limited knowledge of environmental associations in Canada and other countries outside the United States, the majority of CVD prevention strategies are individually-based and are not suitable for population-wide translation, exclusive focus on environmental parameters related to physical activity or nutrition and lack of investigation of perceived and objective measures simultaneously) and incorporate novel aspects through the investigation of environmental determinants across a range of urban and rural communities in 17 countries with fasting lipid levels. Given the dearth of information on the environmental determinants of lipid levels, our hypothesis is based on the established evidence between behaviours such as physical activity, nutrition and tobacco use and their association with lipids, as well as on the growing evidence to suggest that the environment is a predominant determinant of these lifestyle factors.
To this end, we have outlined the following primary hypothesis:
1) Fasting lipid levels will depend on environmental measures (both perceived and objective) that have been found to be associated with physical activity, nutrition and/or tobacco use.
In addition, we have outlined the following secondary hypothesis:
2) The association of perceived and objective environmental measures with fasting lipid levels will depend on a country’s gross national income per capita.
The results of this investigation will provide novel and relevant information that will fill key gaps in our knowledge about the potential environmental causes of elevated CVD risk and thereby inform the development of population- and community-level CVD prevention strategies that will have worldwide relevance.