Your postal code may influence your health, study

Where you live in Canada may play a role in your risk of major diseases like cardiovascular disease, diabetes, and cancer.

Your postal code may influence your health, study
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A new study by McMaster University suggests that your address in Canada could have a major role in diseases like cardiovascular disease, diabetes, and cancer. The study is based on detailed data collected across Canada’s 10 provinces.

Scientists identified patterns connecting health and lifestyle factors like access to public transit, the assortment of fresh fruits of the soil in markets, the costs of famous sustenances, the accessibility and costs of cigarettes and liquor, and the promotion or deficiency in that department, of healthy foods in restaurants.

Russell de Souza, first author of the study said, “We found there are significant differences in environmental factors that may contribute to health, and that these differed between urban and rural communities, as well as when we compared eastern with western, and northern with southern communities.”

“We believe that this information shows there are factors outside of a person’s control that influence the individual’s health, and these factors likely differ depending on where they live.”

More than 2,000 on-the-ground assessments conducted in all of the provinces were collected by trained auditors between 2014 and 2016. The assessment tool was adapted from the McMaster-led Prospective Urban and Rural Epidemiological (PURE) study that simultaneously assesses multiple contextual factors within communities and has been used internationally.

De Souza said, “The rapid increase of overweight and obese Canadians and the associated consequences, including hypertension and diabetes, is a major health problem and threatens to halt the declines in cardiovascular disease deaths that Canada has experienced in the past 30 years.”

“Knowledge gaps exist regarding the impact of the built environment – or the human-made physical surroundings – on how someone develops risk factors like high blood pressure, and the variation of these built environments across Canada by region and rurality.”

Scientists found the correlation between the environmental factor trends aligned with health outcomes tracked in other studies.

De Souza said, “We also see people who live in rural environments tend to have poorer health than people who live in urban environments. This study helps us to understand what we call the ’causes of the causes’ of diseases like cardiovascular disease. For example, what are the factors that lead to the development of high blood pressure, which can later lead to a stroke or high cholesterol, which later turns into a heart attack?”

“By understanding how the built environment plays a role, we can intervene both at an individual level, as well as at a community level. It’s one thing for your doctor to tell you that you need to eat more fruits and vegetables to lower your blood pressure, but what if your grocery store prices are so high that you cannot afford them? Or if to get to your grocery store, you have to drive for 30 minutes? If five to 10 servings of fruit and/or vegetables are recommended daily, we should advocate for everyone to be able to afford and access those servings.”

The findings suggest that:

  • provincial and urban-rural differences exist in the availability of fruits and vegetables, and advertising differs between provinces more so than between urban and rural communities;
  • rural communities face higher food prices, are more subject to seasonal variation in fruit and vegetable selection, and generally see less promotion of healthy restaurant options and availability of nutritional information at restaurants than urban communities;
  • in-store advertising for sweet drinks and junk food are more frequent than in-store advertisements for tobacco products;
  • cigarette prices are lower and the variety of brands is greater in urban than in rural tobacco stores; and are lowest in central Canada, where there is both more in-store advertising for cigarettes and signage prohibiting smoking in stores; and
  • alcohol prices are lowest in Quebec.

Sonia Anand, professor of medicine at McMaster said, “This study is unique because it will enable comparisons between communities within a region, province, and across the country. Place matters as our environment affect our health behaviors without our realizing it.”

“We are making these data available to other researchers and health planners so they can further quantify the impact of the built environment on health, and to help in the building of healthier communities.”

Anne Simard, chief mission and research officer of the Heart and Stroke Foundation of Canada, said: “This study demonstrates that rural, including northern and remote communities, continue to face inequities with respect to access to healthy food options and even nutrition information in restaurants. This underscores the need for policies to improve nutrition in these communities.”

Craig Earle, vice president of cancer control with the Canadian Partnership Against Cancer, added: “The importance of these findings is that they highlight disparities that contribute to different health outcomes depending on where you live. There are things we can collectively take action on today.”

The study was a component of the Canadian Alliance for Healthy Hearts and Minds (CAHHM), a multi-ethnic cohort study being conducted in Canada.

An interactive online map for public use showing the data by postal code is available at http://cvcdcontextual.mcmaster.ca.