Ten Year Trends in Heart Failure
DURHAM, N.C. – Conventional wisdom holds that as the U.S. population ages, the incidence of heart failure will continue to rise. A new study from Duke University Medical Center challenges part of that assumption, however, finding that heart failure is actually declining among the very elderly. Yet the number of heart failure cases overall continues to rise.
"Heart failure is largely a disease of aging, so we were surprised by the findings," says Dr. Lesley Curtis, a health services researcher at Duke and lead author of the study appearing in the February 25 issue of the Archives of Internal Medicine.
Carefully documenting the incidence of a disease – the rate at which it occurs – and the prevalence – how many people have it at any one time – is critically important, because projections have direct bearing upon planning and resources needed for future health care.
Curtis and her colleagues examined data from a five percent sample of Medicare beneficiaries' claims between 1994 and 2003 and found that during that period, 622,789 patients were diagnosed with heart failure.
While the incidence of heart failure fell most sharply among those aged 80 to 84 years old, from 57.5 to 48.4 per 1000 person years, it also rose from 17.5 cases to 19.3 cases per 1000 person-years among those aged 65 to 69 years old.
The study also found that the total number of Americans living with heart failure steadily increased over the ten-year study period, from about 140,000 to 200,000, with more men living with the disease than women.
"From all indications, heart failure will continue to be a major public health burden, consuming billions of dollars each year," says Curtis. Nearly 5 million people in the U.S. suffer from heart failure, and even though mortality from the disease has fallen slightly, it remains a very serious problem. Nearly a third of those diagnosed with heart failure will die within one year, and "that figure hasn't budged over the last decade," according to Curtis, who is also a member of the Duke Clinical Research Institute.
The study was funded by grants from the National Institute on Aging, the National Heart, Lung and Blood Institute and the Agency for Healthcare Research and Quality.
Duke researchers contributing to the study include Drs. David Whellan, Adrian Hernandez and Kevin Schulman, from the Duke Clinical Research Center and Bradley Hammill, Kevin Anstrom and Alisa Shea, from the Center for Clinical and Genetic Economics.