Lessons from Epidemiology: The Burden of Liver Disease

Liver cirrhosis is responsible for more than 1 million deaths annually and the majority of these deaths are preventable. There is marked geographical variation in rates of mortality due to cirrhosis, and this variation in liver disease burden exemplifies the links between population risks for liver disease and mortality. The differing geographical distribution of the major risks factors for the development of liver disease including alcohol consumption, hepatitis C virus (HCV) infection, hepatitis B virus infection, and obesity and the metabolic syndrome has the potential to highlight opportunities for intervention, while the evolution of these risk factors provides insights into understanding the future burden of liver disease. This review focuses on the use of population data to identify high-risk areas and populations that would benefit from preventative interventions to reduce the mortality from liver disease. Specific strategies that are effective at the policy and public health levels are discussed to illustrate the impact these can have if widely implemented. The impact of therapies that have the potential to change the natural history of liver disease, including direct acting antivirals for HCV infection is also described. Finally, the challenges of describing the epidemiology of non-alcoholic fatty liver disease are highlighted to illustrate the need to understand the natural history of disease to inform and influence the development of novel therapies.