Current strategies designed to reduce the toll of hospitalizations for heart failure should be reconsidered and redesigned, according to an analysis published March 18 in the Journal of the American College of Cardiology. Heart failure is a syndrome that includes one or more comorbidities, but clinical and treatment recommendations often assume heart failure is a single disease.

Using the Nationwide Inpatient Sample (NIS) to assess changes in heart failure hospitalizations in the U.S. between 2001 and 2009, researchers found an estimated 37,563,876 hospitalizations with a primary or secondary diagnosis of heart failure from 2001 to 2009. The rate of hospitalization for primary heart failure declined from 29.2 percent in 2001 to 25.6 percent in 2009, an annual decline of 1 percent. But the rate of secondary heart failure rose by 1.6 percent annually over the same period.

Further, the mean age of patients hospitalized with heart failure declined from 74.2 years to 73.1 years. The shift was due to an increase in hospitalizations among patients 18 to 64 and a decrease in patients 65 and older.

Rates of primary heart failure increased among patients aged 18 to 49 and decreased among all other age groups. Rates of secondary heart failure increased among patients aged 18 to 64 but declined in patients aged 65 and older.

At the same time, the mean number of comorbidities increased from 5.58 to 5.91. Cardiovascular comorbidities, including atherosclerosis, arrhythmias and hypertension, were common and increased. The prevalence of several noncardiac comorbidities showed even greater increases. The prevalence of diabetes rose from 35.5 percent to 41.1 percent, renal disease from 10.6 percent to 40.1 percent and mental illness from 25.5 percent to 38.3 percent.

"Our observed increase in secondary heart failure hospitalizations can be partly explained by the high number of rehospitalizations among patients with heart failure," said lead author Saul Blecker, MD, MHS, New York University School of Medicine. "Rehospitalizations most frequently are caused by conditions other than heart failure. Interventions to reduce rehospitalizations and secondary heart failure should include consideration for treatment of comorbid conditions. New models of clinical decision making and care delivery are needed to address the needs of the increasing number of patients with heart failure and comorbid conditions."

In an accompanying editorial comment, Veronique Roger, MD, MPH, FACC, Mayo Clinic, Rochester, Minn., noted, "We need a greater focus on comorbidities across the spectrum of the heart failure syndrome. Strategies to reduce the burden of hospitalizations among heart failure patients should target both cardiac disease and noncardiac conditions."

Keywords: Atherosclerosis, New York, Inpatients, Universities, Heart Diseases, Prevalence, Heart Failure, Hospitalization, United States, Diabetes Mellitus, Hypertension