Abstract 9869: Validation of a Claims-Based Prediction Rule for In-Hospital Pulmonary Embolism Mortality

Abstract

Background: Guidelines suggest that a low risk cohort of patients with pulmonary embolism (PE) may be managed as outpatients or with an abbreviated hospital stay. There is need for a claims-based prediction rule that payers and hospitals can use to efficiently risk stratify PE patients. The authors recently derived a rule found to have high sensitivity and moderate specificity for predicting in-hospital mortality. Objective: To validate the In-hospital Mortality for PulmonAry embolism using Claims daTa (IMPACT) prediction rule using admission claims data. Methods: This analysis was performed using Humana admission claims data from January 2007-March 2014, and included adult patients admitted for their first PE (International Classification of Diseases, ninth edition, Clinical Modification code of 415.1x in in the primary position or secondary position when accompanied by a primary code for a PE complication). The IMPACT rule, consists of age + 11 weighted comorbidities (myocardial infarction, chronic lung disease, stroke, prior major bleeding, atrial fibrillation, cognitive impairment, heart failure, renal failure, liver disease, coagulopathy, cancer), and was used to estimate patients’ risk of in-hospital mortality. Low risk was defined as in-hospital mortality ≤1.5%. IMPACT results are presented as prognostic test characteristic values and 95% confidence intervals (CIs). Results: A total of 23,858 patients (47% male, 77% ≥65 years of age) hospitalized for PE were included and 3.3% died in-hospital. The IMPACT prediction rule classified 2,371 (9.9%) as low-risk (0.8% died); with a sensitivity of 97.6% (95%CI=96.1-98.5), specificity of 10.2% (95%CI=9.8-10.6), and C-statistic of 0.70 (95%CI=0.0.68-0.72), for in-hospital mortality. IMPACT classified 42.7% of patients <65 years old as low-risk; with a sensitivity, specificity and C-statistic of 85.0% (95%CI=77.4-90.5), 43.3% (95%CI=42.0-44.7) and 0.74 (95%CI=0.0.69-0.78), respectively. Conclusion: The IMPACT prediction rule was valid when implemented in a database consisting largely of Medicare claims. The rule has high sensitivity for predicting in-hospital mortality, and may be valuable for identifying PE patients that are candidates for an abbreviated hospital admission.