Nonelective readmissions of medical patients.

Because it is difficult to predict the course of patients discharged from the hospital, we studied 1646 consecutive patients discharged from the medicine service to the care of the hospital's medical staff. Conditions serious enough to warrant urgent or emergent (nonelective) readmissions developed in 278 (16.9%) within 90 days. Multivariate analyses including 14 characteristics of patients at the time of discharge showed five to be significantly associated with readmissions: more frequent ER visits in the 6 months prior to admission, higher BUN levels, arterial PO2 less than 80 mmHg, WBC greater than or equal to 12,000/mm3, and anemia. Using scores from the derived discriminant function, patients could be separated into groups with levels of risk for readmission varying from 7.3% to 38.0%. Nonelective readmission was found to be a frequent and early complication after hospital discharge. The characteristics identified provide a way to recognize high risk patients for clinical interventions.