Patient Differences in Predicting Hospital Mortality for PCI
Patient Differences in Predicting Hospital Mortality for PCI
Background: The Clinical Outcomes Assessment Program (COAP) is a coordinated quality improvement program for percutaneous coronary interventions (PCIs) performed in Washington State hospitals. This study describes the development and testing of models for predicting hospital mortality in patients undergoing PCI.
Methods: The COAP PCI database contains extensive demographic, medical history, and procedural information. This study included 19,358 consecutive PCIs performed in 27 Washington hospitals in 1999 and 2000. The study population was randomly assigned to development (n = 11,591) and test (n = 7614) sets. Logistic regression mortality models were run in the development set and evaluated in the test set.
Results: The test and development sets were similar in demographic, medical history, and procedural characteristics. The overall hospital mortality rate was 1.6% and was similar in the test and development sets. By means of stepwise logistic regression analysis, cardiogenic shock, age, nonelective priority, elevated creatinine level, ejection fraction, number of diseased vessels, myocardial infarction <24 hours from admission, history of chronic obstructive pulmonary disease, male sex, history of peripheral vascular disease, history of PCI, and history of congestive heart failure were identified as predictors of hospital mortality. When applied to the test set, this model had excellent discrimination (c statistic = 0.87, 95% CI = 0.84-0.90). The model was also evaluated in the Northern New England PCI Registry, with very good results (c statistic = 0.85).
Conclusion: Developing risk-adjusted models of mortality and other outcomes is an essential part of the quality improvement process for cardiac revascularization procedures. Because of the rapidly changing nature of PCI, modification of these models in the years to come will be required.
Since its introduction in 1977, the incidence of percutaneous coronary interventions (PCIs) has expanded rapidly, with 539,000 procedures performed in the United States in 1998. In addition, 376,000 procedures with coronary artery stents were performed in that year. Because of the large number of procedures performed, and the associated risk of both mortality and morbidity, numerous studies have identified risk factors, including hospital and operator volumes, for hospital mortality and other adverse events.
Beginning in the early 1990s, a physician-led cardiac outcomes reporting program was instituted in Washington State. These early efforts resulted in the formation of the Clinical Outcomes Assessment Program (COAP), a coordinated quality improvement program for coronary artery bypass graft surgery (CABG) and PCI performed in Washington State hospitals. In 1999, full reporting to hospitals performing CABG and PCI was instituted.
The objective of this study is to use the COAP database to develop and test models for predicting hospital mortality in patients undergoing PCI by dividing the population into development and test sets. This study follows earlier work from New York State, the Registry of the Society for Cardiac Angiography and Interventions, the Cleveland Clinic Foundation, the Northern New England Cardiovascular Disease Study Group, and the American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) and focuses on procedures performed in the era of coronary artery stenting and the use of glycoprotein IIb/IIIa agents.
Background: The Clinical Outcomes Assessment Program (COAP) is a coordinated quality improvement program for percutaneous coronary interventions (PCIs) performed in Washington State hospitals. This study describes the development and testing of models for predicting hospital mortality in patients undergoing PCI.
Methods: The COAP PCI database contains extensive demographic, medical history, and procedural information. This study included 19,358 consecutive PCIs performed in 27 Washington hospitals in 1999 and 2000. The study population was randomly assigned to development (n = 11,591) and test (n = 7614) sets. Logistic regression mortality models were run in the development set and evaluated in the test set.
Results: The test and development sets were similar in demographic, medical history, and procedural characteristics. The overall hospital mortality rate was 1.6% and was similar in the test and development sets. By means of stepwise logistic regression analysis, cardiogenic shock, age, nonelective priority, elevated creatinine level, ejection fraction, number of diseased vessels, myocardial infarction <24 hours from admission, history of chronic obstructive pulmonary disease, male sex, history of peripheral vascular disease, history of PCI, and history of congestive heart failure were identified as predictors of hospital mortality. When applied to the test set, this model had excellent discrimination (c statistic = 0.87, 95% CI = 0.84-0.90). The model was also evaluated in the Northern New England PCI Registry, with very good results (c statistic = 0.85).
Conclusion: Developing risk-adjusted models of mortality and other outcomes is an essential part of the quality improvement process for cardiac revascularization procedures. Because of the rapidly changing nature of PCI, modification of these models in the years to come will be required.
Since its introduction in 1977, the incidence of percutaneous coronary interventions (PCIs) has expanded rapidly, with 539,000 procedures performed in the United States in 1998. In addition, 376,000 procedures with coronary artery stents were performed in that year. Because of the large number of procedures performed, and the associated risk of both mortality and morbidity, numerous studies have identified risk factors, including hospital and operator volumes, for hospital mortality and other adverse events.
Beginning in the early 1990s, a physician-led cardiac outcomes reporting program was instituted in Washington State. These early efforts resulted in the formation of the Clinical Outcomes Assessment Program (COAP), a coordinated quality improvement program for coronary artery bypass graft surgery (CABG) and PCI performed in Washington State hospitals. In 1999, full reporting to hospitals performing CABG and PCI was instituted.
The objective of this study is to use the COAP database to develop and test models for predicting hospital mortality in patients undergoing PCI by dividing the population into development and test sets. This study follows earlier work from New York State, the Registry of the Society for Cardiac Angiography and Interventions, the Cleveland Clinic Foundation, the Northern New England Cardiovascular Disease Study Group, and the American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) and focuses on procedures performed in the era of coronary artery stenting and the use of glycoprotein IIb/IIIa agents.
