Development of pneumonia, myocardial ischemia, or cardiac arrhythmia contributes to nearly two of three hospitalizations for heart failure, according to an article in the April 28 issue of Archives of Internal Medicine.

Researchers analyzed data from the Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure (Optimize-HF), a registry that accounts for 259 hospitals in the United States, in order to identify health factors present at hospital admission that contribute to hospitalization and affect length of hospital stay, re-hospitalization, and mortality both in the hospital and post-discharge.

"Understanding the factors that can exacerbate heart failure and lead to hospitalizations -- especially the ones that are avoidable -- are invaluable to clinicians to help us improve management of heart failure," said first author Gregg C. Fonarow, MD, UCLA's Eliot Corday Chair in Cardiovascular Medicine and Science and director of the Ahmanson-UCLA Cardiomyopathy Center.

According to Fonarow, this is one of the largest studies to examine the frequency that these precipitating factors occur in heart failure patients at admission and to assess the impact they have on clinical outcomes.

Between March 2003 and December 2004, 48,612 eligible patients with heart failure at academic and community hospitals nationwide were enrolled in the registry. A subgroup of 5,791 patients was followed for 60-90 days after hospital discharge to collect additional data on outcomes, including mortality and re-hospitalization rates.

Researchers pinpointed the most frequent factors contributing to hospital admission: Pneumonia or respiratory ailments in 15.3 percent of patients; myocardial ischemia in 14.7 percent, arrhythmia in 13.5 percent, and uncontrolled hypertension in 10.7 patients.

Other factors included not adhering to a special diet (5.2 percent of patients) not taking medications (8.9 percent), and worsening kidney function (6.8 percent).

"Over 60 percent of hospitalized heart failure patients had at least one of these precipitating factors at hospital admission," said Fonarow.

Authors determined that in-hospital mortality rates were lower in patients with none of these factors compared with patients who had one or more of them.

Pneumonia, ischemia and worsening kidney function were associated with higher in-hospital mortality rates and longer length of hospital stays.

"The study offers important insight and points to where we can intervene early, such as making sure patients with heart failure are immunized against flu and pneumonia," added Fonarow.

Non-adherence to diet and uncontrolled hypertension were associated with lower mortality rates and shorter hospital stays.

After discharge follow-up (60 to 90 days) revealed the highest mortality rates occurred in patients who had ischemia or worsening kidney function upon hospital admission. The lowest mortality rates after discharge occurred in patients who had uncontrolled hypertension at admission.

"Learning how these factors influence length of hospital stay, mortality and re-hospitalization are key to helping us better manage patients and preventing future hospitalizations," said Fonarow.