Do Serially Recorded Prognostic Scores Predict Outcome Better Than One-Time Recorded Score on Admission? A Prospective Study in Adult Intensive Care Patients

Abstract

Objectives: The prognosticating ability of one-time recorded Acute Physiology and Chronic Health Evaluation (APACHE) IV score was compared with serially recorded Mortality Prediction Model (MPM) II scores. Design and Methods: A prospective observational study was conducted for a period of 6 months. Acute Physiology and Chronic Health Evaluation IV score was recorded during the first day on intensive care unit (ICU) admission. Mortality Prediction Model II was recorded on admission, 24, 48, and 72 hours. Predicted mortality was compared with observed mortality. The systems were calibrated and tested for discriminant functions. Results: One hundred and fifty patients were studied. The observed mortality was 21.3%. The mean predicted hospital mortality by APACHE IV was 20.6%. The mean predicted hospital mortality rate by serial MPM II measurements was 27.7%, 24.3%, 25.5%, and 25.8%. The area under the receiver–operating characteristic curve was 0.87 for APACHE IV and 0.82, 0.84, 0.85, and 0.89 for MPM II series. Both systems calibrated well with similar degree of goodness of fit. Conclusion: Acute Physiology and Chronic Health Evaluation IV on admission predicted hospital mortality better than serially recorded MPM, which overestimated mortality. Also, APACHE IV had a slightly better discrimination compared to MPM II on admission. One-time recording of APACHE IV on admission may be sufficient for prognostication of ICU patients rather than serial MPM scores.