Heart failure: incidence, case fatality, and hospitalization rates in Western Australia between 1990 and 2005

Abstract

Background: We examined trends in incidence of first-ever (index) hospitalization for heart failure (HF), hospitalization rates, and 30-day and 1-year all-cause mortality subsequent to index hospitalization for HF.

Methods and results: The Western Australia Hospital Morbidity Database was used to identify a retrospective population-based cohort with an index hospitalization for HF in Western Australia between 1990 and 2005. Risk-adjusted temporal trends in mortality were examined with the use of multivariable logistic regression models. Baseline period for comparison was 1990-1993. The cohort (n=19 342; mean age, 74.2+/-13.2 years; 51.3% men) was followed until death or end of 2006. During the period of 1990-2005, age-standardized rates (per 100,000) of index hospitalization for HF as a principal diagnosis decreased from 191.0 to 103.2 in men, with an annual decrease of 3.5%, and from 130.5 to 75.1 in women, with an annual decrease of 3.1%. Risk-adjusted odds ratio of death at 30 days decreased to 0.73 (95% CI, 0.65 to 0.81) based on nonelective admissions. Risk-adjusted odds ratio of 1-year mortality also decreased during the study period in both genders and across all age groups. The total number of HF hospitalizations increased, with nonelective admissions increasing by 14.9% (P for trend, <0.0001) during this period. However, age-standardized rates of nonelective HF hospitalizations decreased during the same period.

Conclusions: During the 16-year period studied, the incidence of index hospitalization for HF in Western Australia decreased steadily in both genders. However, hospitalizations for HF as a measure of health service use increased, despite decreasing rates, partly because of an aging population and improved HF survival.