City slickers are more likely to let high blood pressure become a “silent killer” than their country counterparts, with new research showing that millions of Australians are at risk of sudden death from a stroke or heart attack.

The Heart Foundation has found a city-country divide in data released by the Australian Bureau of Statistics, with a quarter of Australian adults – or four million people – having high blood pressure that is either untreated or treated inadequately.

Researchers discovered that while people in the country are more likely to have high blood pressure than those in the city – 39 per cent compared to 31 per cent – they were also more likely to treat the condition (63 per cent to 48 per cent).

If residents in regional and rural Australia had the same rate of hypertension as those in our cities, close to 570,000 fewer people would have hypertension in these areas, the analysis found.

Heart Foundation chief medical adviser Garry Jennings said research had long shown lower indices of health in regional and rural Australia with higher rates of high blood pressure and obesity, but he was surprised by the difference in treatment.

“There are fewer people in the city with high blood pressure, but a great proportion didn’t have it under control,” Professor Jennings told The New Daily.

He considered a closer relationship between the local GP and patient in regional and rural clinics as a potential explanation, despite less access to health services than metropolitan areas.

Garry Jennings. Photo: The Heart Foundation

“This could tell us something about the health system,” he said. “I wonder if people in the city are less engaged with the health system for more reason.”

Close to six million – more than a third of Australian adults – have hypertension.

Among those who are taking medication for hypertension, one in four or 1.4 million, still have high blood pressure.

The condition is the biggest risk factor for Australia’s greatest killers – heart attack and stroke – but is also the cause of other serious illnesses like dementia and kidney disease.

Professor Jennings said the ABS data also revealed the most “at risk groups” across Australia, including men between the age of 55 and 65 and older women.

The prevalence of hypertension is higher for Australian men – 35 per cent or three million adults – compared to 32 per cent or 2.9 million women.

He said the stats had “flat-lined” in Australia in the past 20 years despite more information about reducing the risks of heart disease such as a healthy diet and exercise.

“In those groups where we’ve seen falls for decades, we’re seeing increases again,” Professor Jennings said. “Men don’t go to the doctors for check ups unless they’re forced along by their partners,” he added.

The Heart Foundation is raising awareness about high blood pressure during Heart Week, which runs from April 30 to May 7.