Disease burden is an important indicator of the state of health of a population. It can be measured as the frequency (e.g. incidence and prevalence) of a condition or its effects including: fatal and non-fatal health loss from disease (e.g. disability-adjusted life years (DALYs)) as well as the financial costs (e.g. direct health care costs and indirect health care expenditures related to lost income due to premature death). Accurate disease burden information is essential for policy-making such as prioritization of health interventions and allocation of resources. Chronic Liver Disease (CLD) causes substantial health and economic burden in the US, where nearly two million deaths annually are attributable to CLD. In the recent past, overall mortality rate of CLD has been increasing. Viral hepatitis and alcoholic liver disease are thought to be the most common etiologies of chronic liver diseases. More recently, the prevalence of non-alcoholic steatohepatitis (NAFLD) is rapidly increasing and non-alcoholic steatohepatitis (NASH) has become a leading indication for liver transplantation. In this work, we assemble available data on the burden of CLD in the United States, focusing on non-malignant complications, whereas the impact on mortality and healthcare expenses of hepatocellular carcinoma (HCC), an important consequence of CLD is discussed elsewhere.

Background and Aims Cirrhosis from hepatitis C virus (HCV) infection is a major cause of end-stage liver disease and hepatocellular carcinoma worldwide. We determine the prevalence of cirrhosis among HCV-infected American adults including those unaware of their infection. Methods Using the National Health and Nutrition Examination Survey (NHANES) data, we identified participants aged≥20 years with detectable serum HCV RNA. The prevalence of advanced fibrosis and cirrhosis was determined for Eras 1 (1988-94), 2 (1999-2006) and 3 (2007-12) by using FIB-4 > 3.25 and APRI > 2.0, respectively. Results Out of 52,644 NHANES examinees, 49,429 were tested for HCV, of whom 725 met the inclusion criteria (positive HCV RNA with available data for FIB-4 and APRI). Based on APRI, 6.6% (95% confidence interval [CI]:2.2-11.0) of HCV-infected adults in Era 1, 7.6% (95%CI:3.4-11.8) in Era 2 and 17.0% (95%CI:8.0-26.0) in Era 3 had cirrhosis. In the multivariable regression analysis, this era effect was attributable to increasing age (odds ratio [OR]:1.04, 95%CI:1.02-1.07), diabetes (OR:2.33, 95%CI:1.01-5.40) and obesity (OR:2.96, 95%CI:1.15-7.57). Cirrhosis was as common among respondents who were unaware of their infection as those who were aware (both 11%). Results were identical when FIB-4 was used. Conclusions Among HCV-infected American adults, the proportion with cirrhosis has increased rapidly. Cirrhosis prevalence remains high in individuals unaware of their HCV infection. These data highlight the urgency for HCV screening regardless of symptoms, systematic assessment for liver fibrosis in those with HCV infection and institution of antivirals to prevent advanced liver disease.

Ultrasound‐based elastography and serum indexes have been individually validated as noninvasive methods for staging liver fibrosis in chronic viral hepatitis. We aimed to compare the accuracy of transient elastography (TE), shear wave elastography (SWE), aspartate aminotransferase to platelet index (APRI) and Fibrosis‐4 index (FIB‐4) with the METAVIR liver fibrosis staging in viral hepatitis patients. We enrolled 121 treatment‐naïve chronic hepatitis B and C monoinfected patients. All underwent liver biopsy had biochemistry tests and liver stiffness measurements by TE using M and XL probes followed by point SWE performed on the same day. The accuracy of each method for predicting different fibrosis stages was demonstrated as an area under the receiver operating characteristic (AUROC) curves. The AUROCs of TE using M and XL probes, SWE, APRI and FIB‐4 were 0.771, 0.761, 0.700, 0.698 and 0.697, respectively, for significant fibrosis; 0.974, 0.973, 0.929, 0.738 and 0.859, respectively, for advanced fibrosis; and 0.954, 0.949, 0.962, 0.765 and 0.962, respectively, for cirrhosis. TE using the M probe was comparable to the XL probe in detecting all fibrosis stages. TE was superior to SWE for assessing significant fibrosis and advanced fibrosis. For cirrhosis, the performances of TE, SWE and FIB‐4 were similar. APRI was least accurate in liver fibrosis staging. To conclude, for patients with viral hepatitis, TE using either M or XL probe is an effective noninvasive test for assessing liver fibrosis, particularly advanced fibrosis and cirrhosis, while SWE and FIB‐4 possess an excellent accuracy in predicting cirrhosis.