Feb. 26 (HealthDay News) -- While the number of elderly Americans newly diagnosed with heart failure has declined, the number of those living with the condition has increased, new research finds.

The Duke University study analyzed data on 622,789 Medicare patients, aged 65 and older, diagnosed with heart failure between 1994 and 2003. It found that the annual occurrence of heart failure decreased from 32 per 1,000 person-years (years of observation time during which each person is at risk to develop the disease) in 1994, to 29 per 1,000 person-years in 2003.

When the researchers looked at specific age groups, they found a sharper decline among people aged 80 to 84 (from 57.5 to 48.4 per 1,000 person-years), and a slight increase among those aged 65 to 69 (from 17.5 to 19.3 per 1,000 person years).

Between 1994 and 2003, the number of people living with heart failure increased, from about 140,000 to 200,000. More men than women live with the condition.

"The proportion of [Medicare] beneficiaries with a heart failure diagnosis increased from 90 per 1,000 in 1994 to 120 per 1,000 in 2000, and remained at about 120 per 1,000 through 2003," the authors wrote.

The findings are published in the Feb. 25 issue of the Archives of Internal Medicine.

"Although the incidence of heart failure has declined somewhat during the past decade, modest survival gains have resulted in an increase in the number of patients living with heart failure," the researchers concluded. "Identifying optimal strategies for the treatment and management of heart failure will become increasingly important as the size of the Medicare population grows."

Almost 5 million people in the United States have heart failure, which kills more than 300,000 patients a year. Since it's primarily a disease of older people, it places a significant and increasing burden on Medicare, said the study authors, who noted that the number of people age 65 and older hospitalized for heart failure increased by more than 30 percent from 1984 to 2002.

SOURCE: JAMA/Archives journals, news release, Feb. 25, 2008