By Amy Norton
NEW YORK (Reuters Health) - The number of people developing chronic heart failure in Ontario has fallen substantially in recent years, a new study finds.
Between 1997 and 2007, new cases of heart failure dropped by one-third in the Canadian province - from 455 cases for every 100,000 people, to 306 per 100,000.
"There's been a remarkable decline," said senior researcher Dr. Jack V. Tu, of the University of Toronto in Ontario.
The findings, published in the Canadian Medical Association Journal, come from only one province, but Tu said it's likely the same trend is happening in the rest of Canada, as well as the U.S.
Heart failure is a chronic condition in which the heart cannot pump blood efficiently enough to meet the body's demands - causing symptoms like fatigue, breathlessness and fluid buildup in the limbs.
Most often, people develop heart failure because of damage to the muscle from a heart attack or coronary heart disease - where cholesterol-containing "plaques" gradually clog the heart arteries.
According to Tu, Ontario's decline in heart failure probably owes much to the known decline in heart disease and heart attacks.
"It may also be because of better control of high blood pressure, which is a major risk factor for heart failure," Tu noted in an interview.
Past studies - in Canada, the U.S., Europe and elsewhere - have found that hospital admissions for heart failure have been dropping since the mid-1990s. But it has not been clear whether that's because fewer people are developing heart failure, Tu explained.
It could just be that fewer people with heart failure are landing in the hospital.
PROGNOSIS STILL POOR
So for their study, Tu's team combed through data from hospitals and doctors' practices.
They found that over a decade, nearly 420,000 Ontario residents were newly diagnosed with heart failure. But the rate steadily declined over time.
"The less good news," Tu said, "is that if you do develop the condition, the prognosis is still poor."
In 1997, 27 percent of people diagnosed with heart failure died within a year. By 2007, that figure was just over 25 percent. And if people were hospitalized for heart failure, 36 percent died within a year in 1997, while 34 percent died in 2007 -- an insignificant difference in statistical terms.
"The best thing would be to prevent heart failure in the first place," Tu said.
That means controlling blood pressure and other risk factors for coronary heart disease, like high cholesterol, smoking, obesity and diabetes.
There is some concern that the drop in heart failure could "plateau" or even reverse, Tu noted. That's because of high rates of obesity and rising rates of type 2 diabetes among young people.
When it comes to heart failure rates, Tu said, "things have definitely been getting better. But we do need to keep monitoring this."
SOURCE: http://bit.ly/MMUFb0 Canadian Medical Association Journal, online August 20, 2012.