HF burden increasing in USA

By Caroline Price
26 February 2008
Arch Intern Med 2008; 168: 418-424

MedWire News: The prevalence of heart failure (HF) has increased recently in the USA, despite a decline in its incidence, study findings indicate.

They show that the incidence of HF fell overall among both men and women from 1994 to 2003, but, owing to improved survival rates, the number of people living with HF increased during this period.

Lesley Curtis (Duke University School of Medicine, Durham, North Carolina) and colleagues studied a nationally representative 5% sample of Medicare beneficiaries, of whom 622,786 were diagnosed with HF between 1994 and 2003.

"Estimates of the incidence and prevalence of HF in elderly persons translate directly into projections of resource use for the Medicare program, so accurate estimates are essential," they note.

The researchers report in the Archives of Internal Medicine that the incidence of HF declined slightly from 32 per 1000 person-years in 1994 to 29 per 1000 person-years in 2003 (p<0.01).

The incidence actually increased over this time in patients aged 65-69 years, but this was offset by the decline among patients aged 75 years or over.

Meanwhile, the prevalence of HF increased steadily from around 140,000 in 1994 to 200,000 in 2003. These numbers equated to rates of around 90 and 121 per 1000 beneficiaries, respectively. Each yearly increase in the prevalence rate was significant (p<0.01) for the whole group and in both men and women.

The increase in prevalence reflected improved survival rates. Between 1994 and 2003, both unadjusted and risk-adjusted mortality declined slightly. Risk-adjusted 30-day mortality decreased by over 5%, from 13.0% to 12.6% in men and from 11.5% to 10.8% for women. There was a 5% decrease in 1-year mortality, from 28.9% to 27.5% overall. And 5-year mortality fell by 3%, from 67.5% to 64.9% in men and from 61.7% to 60.2% in women.

Closer inspection showed that the rate of increase in prevalence slowed over time, growing from 90 per 1000 beneficiaries in 1994 to 121 per 1000 in 2000, after which it remained at around 120 per 1000 up to 2003. This reflected declines in incidence and relatively steady mortality rates, the authors note.

They conclude: "Identifying optimal strategies for the treatment and management of HF will become increasingly important as the size of the Medicare population grows."
Curtis commented: "From all indications, HF will continue to be a major public health burden, consuming billions of dollars each year."

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