Why healthy communities may equal a healthy heart

A partnership between researchers from the Cumming School of Medicine (CSM) and Waseda University in Tokyo, Japan is contributing to our understanding of how ‘where we live’ is connected to cardiovascular disease (CVD), the leading cause of death in Canada.

CVD risk factors such as diet, smoking and exercise are well established, but researchers have just recently begun to look at the link between the communities where we live, work and play, and developing the disease.

“We know there is a connection between certain neighbourhood characteristics, such as population density, and cardiovascular disease, but the ‘why’ and the ‘how’ are not well established,” says Dr. Gavin McCormack, PhD, a member of the O’Brien Institute for Public Health at the CSM.

In their paper published in Nature Reviews Cardiology, Drs. Javad Koohsari, PhD, Koichiro Oka, PhD, Tomoki Nakaya, PhD, with Waseda University, and McCormack identify gaps in our current knowledge and provide a framework to help guide future research on the relationships between CVD and the neighbourhoods and cities in which we live.

• Photo above, from left: Koichiro Oka, Javad Koohsari and Gavin McCormack at Waseda University in Japan in 2019. Photo courtesy Gavin McCormack

They say this information is critical for the development of policies and interventions to make communities healthier.

“We are trying to make sense of a complex relationship — the pathways by which where we live affects cardiovascular health,” says McCormack, who is also a member of the Libin Cardiovascular Institute.

It’s tricky because neighbourhood characteristics may have different effects on CVD risk factors for different people.

For example, a neighbourhood with high population density could provide more opportunities to be physically active and access healthier food options — factors that could lower the risk of developing CVD. But high population density may also have negative effects on older adults’ blood pressure, a known risk factor for CVD, through more exposure to air pollution.

“When we find positive associations between higher density neighbourhoods and CVD, the next important questions we need to answer are ‘Hw much density is needed to positively influence CVD risk factors?’ and ‘Where does it need to be concentrated?’” These benchmarks may also vary depending on different regions and countries, he says.  

Much of the current knowledge has to do with the relationship between CVD and neighbourhood characteristics, such as such as transportation infrastructure, parks, walkability and access to healthy food. Although investigating these relationships is a necessary first step, McCormack says these studies cannot provide urban designers and policy-makers with benchmarks for translating the findings into practice.

What makes a heart-healthy neighbourhood?

Researchers know that decisions about neighbourhood design and planning can have significant impacts on people’s social, mental and physical health, including whether or not someone develops chronic disease later in life.

With this in mind, the Calgary-Tokyo research team has been working in collaboration over several years on a series of studies in Japan and Canada that look at the relationship between urban design and cardiovascular health.

“There are huge differences between the way communities are built in Japan versus Canada,” says Koohsari, an assistant professor in urban design and health at Waseda University in Japan. “For example, Japanese cities are dense and compact, while Canadian environments have a lower density.”

The Canada-Japan collaboration has enabled the researchers to test how some of the same neighbourhood characteristics may influence CVD risk factors such as physical activity, obesity and sedentary behaviour in an Asian city like Tokyo compared with a Western city like Calgary. Koohsari says this knowledge will help to produce localized evidence urban designers and public health practitioners can use in both contexts to ensure communities are better designed with cardiovascular health in mind.

“We hope that future studies will provide evidence-based information on how to design or redesign communities to promote cardiovascular health,” says Koohsari. “This knowledge will be key to identify possible targets for prevention and policy efforts.”

Gavin McCormack is an associate professor in the Department of Community Health Sciences, Cumming School of Medicine, and an adjunct associate professor in the Faculty of Kinesiology and the School of Architecture, Planning and Landscape at the University of Calgary.