The Burden of Hepatitis C Infection-Related Liver Fibrosis in the United States.

BACKGROUND: Knowledge of the estimated proportion of hepatitis C virus (HCV)-infected persons with advanced fibrosis or cirrhosis is critical to estimating healthcare needs.
METHODS: We analyzed HCV-related testing conducted by Quest Diagnostics from January 2010 through December 2013. Tests included hepatitis C antibody, HCV RNA, HCV genotype (nucleic acid tests [NAT]), liver function tests, and platelet counts; patient age was also determined. Aspartate aminotransferase (AST)-to-platelet ratio (APRI) was calculated as = 100*(aspartate aminotransferase [AST]/upper limit of AST)/platelet. Fibrosis-4 (FIB-4) was calculated as (age × AST)/(platelet ×√ alanine aminotransferase [ALT]). Persons were "currently infected" if they had ≥1 positive HCV NAT; "in care" if a positive RNA test was followed <6 months by ≥1 additional NAT(s), or ALT, AST, and platelets <90 days, or any test ordered by an infectious diseases or gastroenterology specialist; and "evaluated for treatment" if they had a genotype test.
RESULTS: Approximately 10 million HCV test results were analyzed, representing 5.6 million unique patients. Of the 2.6 million patients with data to estimate liver disease, 5% were currently infected. Among those currently infected, APRI and FIB-4 scores indicated that 23% overall-and 27% among the cohort born during 1945-1965-had advanced fibrosis or cirrhosis at first diagnosis. A total of 54% of infected were in care and 51% of infected with advanced fibrosis or cirrhosis were evaluated for treatment.
CONCLUSIONS: Testing from a large US commercial laboratory indicates that about 1 in 4 HCV-infected persons have levels of liver disease put them at highest risk for complications and could benefit from immediate antiviral therapy. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.