1Division of Gastroenterology and Hepatology, Henry Ford Health System, Detroit, Michigan, USA.
2Department of Public Health Sciences, Henry Ford Health System, Detroit, Michigan, USA.
3Center for Health Policy and Health Services Research, Henry Ford Health System, Detroit, Michigan, USA.
4Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
5Center for Health Research, Geisinger Health System, Danville, Pennsylvania, USA.
6Center for Health Research, Kaiser Permanente-Hawaii, Honolulu, Hawaii, USA.
7Center For Health Research, Kaiser Permanente-Northwest, Portland, Oregon, USA.
The severity of liver disease in the hepatitis C virus (HCV)-infected population in the United States remains uncertain. We estimated the prevalence of cirrhosis in adults with chronic hepatitis C (CHC) using multiple parameters including liver biopsy, diagnosis/procedure codes, and a biomarker.
Patients enrolled in the Chronic Hepatitis Cohort Study (CHeCS) who received health services during 2006-2010 were included. Cirrhosis was identified through liver biopsy reports, diagnosis/procedure codes for cirrhosis or hepatic decompensation, and Fibrosis-4 (FIB-4) scores ≥5.88. Demographic and clinical characteristics associated with cirrhosis were identified through multivariable logistic modeling.
Among 9,783 patients, 2,788 (28.5%) were cirrhotic by at least one method. Biopsy identified cirrhosis in only 661 (7%) patients, whereas FIB-4 scores and diagnosis/procedure codes for cirrhosis and hepatic decompensation identified cirrhosis in 2,194 (22%), 557 (6%), and 482 (5%) patients, respectively. Among 661 patients with biopsy-confirmed cirrhosis, only 356 (54%) had an International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code for cirrhosis. Older age, male gender, Asian race, Hispanic ethnicity, genotype 3 infection, HIV coinfection, diabetes, history of antiviral therapy, and history of alcohol abuse were independently associated with higher odds of cirrhosis (all, P<0.05). Conversely, private health insurance coverage, black race, and HCV genotype 2 were associated with lower odds of cirrhosis.
A high proportion of patients with biopsy-confirmed cirrhosis are not assigned ICD-9 codes for cirrhosis. Consequently, ICD-9 codes may not be reliable as the sole indicator of the prevalence of cirrhosis in cohort studies. Use of additional parameters suggests a fourfold higher prevalence of cirrhosis than is revealed by biopsy alone. These findings suggest that cirrhosis in CHC patients may be significantly underdocumented and underdiagnosed.