Skip to main content

The Globe and Mail

Hypertension under diagnosed and poorly controlled, Canadian study shows

Hypertension, or high blood pressure, is referred to by the World Health Organization as one of the world’s biggest silent killers because most people who have it can’t feel or see it.

Thomas Kienzle/AP

A large Canadian-led study shows that even though the risks posed by high blood pressure are well known, the condition remains under-diagnosed and poorly controlled around the world.

The study, which was conducted in 17 countries, showed that 41 per cent of adults tested had high blood pressure.

But just under half of those people were aware they had the problem.

Story continues below advertisement

Of those who knew they had hypertension, 88 per cent were receiving some drug therapy for the condition.

But only about one-third of the people taking medication had their blood pressure under control.

The new president of the World Hypertension League says the findings are evidence of a widespread failure to address hypertension prevention and control.

"There's a recognition that this needs to be dealt with," said Dr. Norm Campbell, a professor of medicine at the University of Calgary who has been a leader of Canadian efforts to combat hypertension.

"We need very, very strong government leadership, both for prevention but for also evolution of our health-care system."

Campbell was not involved in this study, which was led by researchers at McMaster University in Hamilton, Ont. The study was published Tuesday in the Journal of the American Medical Association.

The findings come from the PURE study – the acronym stands for Prospective Urban Rural Epidemiology – which is designed to track how urbanization is affecting risk factors for and rates of cardiovascular disease in various parts of the world.

Story continues below advertisement

The 17 countries in the study represent a mixture of upper income, developing and low income nations.

People with hypertension in higher income countries were more likely to be aware of their condition than people in lower income countries. The same was true for the likelihood that a person with high blood pressure would be treated.

Dr. Koon Teo, a cardiologist and epidemiologist, is one of the co-lead authors of the paper. He says the findings aren't surprising, but point to the need for much more work in the field of blood pressure control.

"Lots of people don't know they have hypertension. And even those who know about their hypertension, a proportion did not receive treatment. And of those who received treatment, blood pressure is not well controlled," Teo said.

Campbell suggested the tragedy of hypertension – a leading cause of death and disability worldwide – is that it is largely preventable.

"If we look back to hunter-gatherer societies, which are almost non-existent now, they might have had five per cent of the population hypertensive, with very little increase of blood pressure with age," said Campbell, who began his term as head of the World Hypertension League on Tuesday.

Story continues below advertisement

"So this is really something that we've done to our society by becoming physically inactive, obese and eating highly processed foods with lots of salt, low potassium, low fibre, etc."

Campbell said the study shows that he has his work cut out for him.

Report an error

The Globe invites you to share your views. Please stay on topic and be respectful to everyone. For more information on our commenting policies and how our community-based moderation works, please read our Community Guidelines and our Terms and Conditions.

We’ve made some technical updates to our commenting software. If you are experiencing any issues posting comments, simply log out and log back in.

Discussion loading… ✨

Combined Shape Created with Sketch.

Combined Shape Created with Sketch.

Thank you!

You are now subscribed to the newsletter at

You can unsubscribe from this newsletter or Globe promotions at any time by clicking the link at the bottom of the newsletter, or by emailing us at