Changing incidence and survival for heart failure in a well-defined older population, 1970-1974 and 1990-1994

Abstract

Background: An epidemic increase in heart failure (HF) mortality, hospitalization, and prevalence rates has been observed among older persons in recent years. It is unclear whether this reflects an increase in incidence or survival.

Methods and results: We conducted a retrospective cohort study comparing HF in 1970 to 1974 and 1990 to 1994 among persons > or =65 years old belonging to a large, well-defined population with complete medical records available for research. Using Framingham clinical criteria, we identified incident cases of HF in the respective periods. Age-specific and age-adjusted incidence, mortality, and survival rates were compared. Cox proportional-hazards models were used to assess association of comorbidities and medications with survival. During 38,800 and 127,419 person-years for 1970 to 1974 and 1990 to 1994, respectively, 387 and 1555 confirmed incident cases were identified. When adjusted for age, incidence increased by 14% (95% CI 2% to 28%). Increased incidence tended to be greater for older persons and for men. Based on 5-year follow-up and adjustment for age and comorbidities, the mortality hazards decreased 33% (95% CI 14% to 48%) among men and 24% (95% CI -1% to 43%) among women.

Conclusions: The epidemic increase in HF among the older population between the 1970s and 1990s is associated with increased incidence and improved survival, with both of these effects being greater in men.