Changes in cardiovascular hospitalization and comorbidity of heart failure in the United States: findings from the National Hospital Discharge Surveys 1980-2006.

OBJECTIVE: This study aimed to update the long-term trend of coronary heart disease (CHD), cerebrovascular disease (CBVD), and heart failure (HF) hospitalization rates and HF comorbidity among adults aged 65 and older in the United States.
METHODS: Data from the National Hospital Discharge Surveys between 1980 and 2006 were used. CHD, CBVD, and HF were defined using the principal (first-listed) diagnosis of disease at hospital discharge according to the ICD-9-CM code. Census estimated population data (2000) were used to estimate age and gender-specific hospitalization rates.
RESULTS: Age-adjusted CHD and CBVD hospitalization rates have significantly decreased between 1980 and 2006, with an estimated annual decrease rate of 2.24% for CHD and 1.55% for CBVD in men, and 2.36% for CHD and 1.34% for CBVD in women. However, the absolute numbers of CHD and CBVD hospitalization continued to increase partly because of the aging population. Furthermore, HF hospitalization rates have significantly increased with an estimated annual rate increase of 1.20% in men and 1.55% in women between 1980 and 2006. Of six selected co-morbidities, about 50% in men and 40% in women with HF had a coexisting disease of CHD, followed by chronic obstructive pulmonary disease, diabetes mellitus, renal failure, and pneumonia.
CONCLUSIONS: While the burden of CHD and CBVD remains the major public health problem, HF has emerged as a new challenge in cardiovascular disease control, characterized by increased trends of HF hospitalization and increased comorbidities from major diseases.