Accurate Identification of Patients with Cirrhosis and Its Complications in the Electronic Health Record

Abstract

Background: Cirrhosis represents a significant health burden; administrative data provide an important tool for research studies.

Aims: We aimed to understand the validity of current ICD-10 codes compared to previously used ICD-9 codes to identify patients with cirrhosis and its complications.

Methods: We identified 1981 patients presenting to MUSC between 2013 and 2019 with a diagnosis of cirrhosis. To validate the sensitivity of ICD codes, we reviewed the medical records of 200 patients for each associated ICD 9 and 10 codes. Sensitivity, specificity, and positive predictive value for each ICD code (individually or when combined) were calculated and univariate binary logistic models, for cirrhosis and its complications, predicted probabilities were used to calculate C-statistics.

Results: Single ICD 9 and 10 codes were similarly insensitive for detection of cirrhosis, with sensitivity ranging from 5 to 94%. However, ICD-9 code combinations (when used as either/or) had high sensitivity and specificity for the detection of cirrhosis, with the combination of either 571.5 (or 456.21) or 571.2 codes having a C-statistic of 0.975. Combinations of ICD-10 codes were only slightly less sensitive and specific than ICD-9 codes for detection of cirrhosis (K76.6, or K70.31, plus K74.60 or K74.69, and K70.30 had a C-statistic of 0.927).

Conclusions: ICD-9 and ICD-10 codes when used alone were inaccurate for identifying cirrhosis. ICD-10 and ICD-9 codes had similar performance characteristics. Combinations of ICD codes exhibited the greatest sensitivity and specificity for detection of cirrhosis, and thus should be used to accurately identify cirrhosis.

Keywords: Decompensation; International Classification of Diseases (ICD) code; Liver; Portal hypertension.