Assessing the Use of International Classification of Diseases-10th Revision Codes From the Emergency Department for the Identification of Acute Heart Failure

OBJECTIVES The objective of this study was to compare administrative codes with chart review for patients with acute heart failure (AHF). BACKGROUND Administrative databases are used in population health research; however, the validity of codes in the emergency department (ED) for AHF compared with chart review is uncertain. METHODS A cohort of 952 patients with suspected AHF were prospectively recruited from 4 EDs in Edmonton, Alberta, Canada, from 2009 to 2012. Patients had their diagnoses adjudicated by expert physicians using a standardized scoring system and detailed chart review. ED and hospital discharge International Classification of Diseases-10th Revision (ICD-10) codes were captured in the main diagnosis or in any diagnostic field. RESULTS The 897 patients had a median age of 77 years (interquartile range: 67 to 85 years), and 806 (90%) were admitted to the hospital. Overall, 809 patients (90.2%) had AHF by adjudication and 660 (73.6%) had ICD-10 code I50. x as a main diagnosis in the ED administrative data, respectively. The positive predictive value of an AHF main diagnosis in the ED administrative data was 93.3% (95% confidence interval [CI]: 92.0% to 94.7%), with sensitivity of 76.1% (95% CI: 75.0% to 77.2%) and specificity of 50.0% (95% CI: 39.8% to 60.1%). The positive predictive value for AHF in any diagnostic field of the ED administrative data was 92.0% (95% CI: 91.1% to 93.0%), with a sensitivity of 89.4% (95% CI: 88.5% to 90.4%) and specificity of 28.4% (95% CI: 20.1% to 37.9%). CONCLUSIONS An ICD-10 I50. x diagnosis in the ED is highly predictive of AHF compared with chart-level adjudication using a validated score. Thus, the use of these codes in ED administrative databases could identify AHF for clinical and epidemiological studies. (C) 2015 by the American College of Cardiology Foundation.