Incidence and survival of hospitalized acute decompensated heart failure in four US communities (from the Atherosclerosis Risk in Communities Study)

Abstract

Most population-based estimates of incident hospitalized heart failure (HF) have not differentiated acute decompensated heart failure (ADHF) from chronic stable HF nor included racially diverse populations. The Atherosclerosis Risk in Communities Study conducted surveillance of hospitalized HF events (age ≥55 years) in 4 US communities. We estimated hospitalized ADHF incidence and survival by race and gender. Potential 2005 to 2009 HF hospitalizations were identified by International Classification of Diseases, Ninth Revision, Clinical Modification, codes; 6,168 records were reviewed to validate ADHF cases. Population estimates were derived from US Census data; 50% of eligible hospitalizations were classified as ADHF, of which 63.6% were incident ADHF and 36.4% were recurrent ADHF. The average incidence of hospitalized ADHF was 11.6 per 1,000 persons, aged ≥55 years, per year, and recurrent hospitalized ADHF was 6.6 per 1,000 persons/yr. Age-adjusted annual ADHF incidence was highest for black men (15.7 per 1,000), followed by black women (13.3 per 1,000), white men (12.3 per 1,000), and white women (9.9 per 1,000). Of incident ADHF events with heart function assessment (89%), 53% had reduced the ejection fraction (heart failure with reduced ejection fraction [HFrEF]) and 47% had preserved ejection fraction (heart failure with preserved ejection fraction [HFpEF]). Black men had the highest proportion of acute HFrEF events (70%); white women had the highest proportion of acute HFpEF (59%). Age-adjusted 28-day and 1-year case fatality after an incident ADHF was 10.4% and 29.5%, respectively. Survival did not differ by race or gender. In conclusion, ADHF hospitalization and HF type varied by both race and gender, but case fatality rates did not. Further studies are needed to explain why black men are at higher risk of hospitalized ADHF and HFrEF.

Figure 1

Age-adjusted rates of first, recurrent, and all hospitalized ADHF events: 2005 to 2009 Atherosclerosis Risk in Communities Heart Failure Community Surveillance. Rates are adjusted for age by the direct method, according to the distribution of the US population in 2000. *p Value <0.05 for the gender-specific comparison between black and white groups.

Figure 2

Age-adjusted 1-year mortality curves for incident hospitalized ADHF cases: 2005 to 2009 Atherosclerosis Risk in Communities Heart Failure Community Surveillance.

Figure 3

Age-adjusted (A) 28-day and (B) 365-day CF percentages and 95% CI for incident hospitalized ADHF cases: 2005 to 2009 Atherosclerosis Risk in Communities Heart Failure Community Surveillance. All percentages are adjusted for age by direct method using the ARIC combined hospitalized HF events as the standard. Gender-specific CF percentages are also adjusted for race. Minor discrepancies with the mortality curve (Figure 2) are because of differences in age-adjustment methods.