Prediction of mortality for congestive heart failure patients: results from different wards of an italian teaching hospital

Congestive heart failure (CHF) constitutes an important public health problem in Italy, evidenced by the high number of hospital admissions each year. Significant inter-hospital as well as interward differences in mortality rates for CHF patients that have been described may, in part, be explained by the differences in the severity of the illness of admitted patients. The goal of this study was to predict 30-day severity-adjusted mortality risk in patients with CHF admitted to wards of a teaching hospital in Siena, Italy, in 1997. A 30-day mortality was determined by linking hospital discharge files with the Tuscany Mortality Registry database. The 3M all patient refined diagnosis related group (APR-DRG) software was used as a risk assessment method. The relationships between death and the following variables were studied by univariate analyses: APR-severity risk, APR-mortality risk, age, sex, length of stay and, discharge ward. Multivariate analysis was also performed to verify the associations between death and those parameters found to be significant by univariate analysis. Unadjusted mortality proportions ranged from 4.3 to 44.0%. Logistic regression analysis demonstrated that APR-mortality risk, length of stay, and discharge ward were significantly and independently associated with 30-day mortality risk in patients with CHF. In summary, 30-day mortality risk varied significantly according to the ward of discharge in an Italian teaching hospital, even after adjustment for severity of illness.