Global Burden of Chronic Liver Diseases: the role of Nonalcoholic Fatty Liver Disease
14 May 2020
Chronic hepatitis B virus (HBV), hepatitis C virus (HCV), nonalcoholic fatty liver disease (NAFLD), and alcoholic liver disease (ALD) are main causes of chronic liver disease (CLD). Worldwide, chronic liver disease (CLD) is a major cause of morbidity and mortality, with 2 million individuals dying of liver disease each year (1,2). In this context, CLD is the 10th cause of death worldwide (1-3). In addition to mortality, CLD leads to significant impairment of patients’ quality of life and is responsible for significant morbidity and economic burden. The widespread of HBV vaccination, the impact of the WHO global efforts to eradicate viral hepatitis and the global epidemic of obesity and type 2 diabetes may have changed the epidemiology of CLD in the last two decades (3).
Paik J.M. et al (3) in a recent study analyzed the Global Burden Disease (GBD) database to provide a global perspective about the two important consequences of CLD (liver cancer and cirrhosis) in 2017 to include the trends in the incidence, mortality, and disability-adjusted life-year (DALY) rates since 2012. The global incidence and mortality of cirrhosis and liver cancer combined (26.68 per 100,000) in 2017 was higher than diabetes (17.5 per 100,000), chronic kidney disease (15.93 per 100,000), and hypertensive heart disease (12.28 per 100,000) (3). Furthermore between 2012 and 2017, a 7.2% increase in the incidence of cirrhosis and 8.7% increase in cirrhosis-related deaths were noted. Additionally, there was a 21% increase in the incidence of liver cancer (LC) and a 16% increase in LC-related deaths. There was a positive trend in mortality from viral causes, as death rates from cirrhosis due to HBV decreased globally and a similar improvement was observed for cirrhosis due to HCV in 13 out of 21 GBD regions. Conversely, 16 out of 21 GBD regions showed worsening trends in incidence of cirrhosis due to NAFLD as well as worsening trends in mortality due to cirrhosis from NAFLD. Similar results have been shown for ALD, which is the most common etiology of cirrhosis in Latin America and Central Europe.
These data are confirmed in the paper recently published by Lancet Gastroenterology and Hepatology (4), in which the authors analyzed the incidence of CLD between 1990 and 2017, observed a doubling in the number of deaths, a more than tripling in prevalent cases of decompensated cirrhosis, and a more than doubling in prevalent cases of compensated cirrhosis due to NASH. Unlike the other four causes studied (ALD, HBV and HCV), NASH was the only one not to show a decreasing trend in age- standardized death rates.
Life style modifications could easily prevent the progression of chronic liver disease due to NASH and alcohol. Future studies are needed to evaluate if screening strategies in general or at risk populations, could reduce the burden of these preventable causes of chronic liver disease.
- Asrani SK, Devarbhavi H, Eaton J, Kamath PS. Burden of liver diseases in the world. J Hepatol 2019;70:151-171.
- Younossi Z, Henry L. Contribution of alcoholic and nonalcoholic fatty liver disease to the burden of liver-related morbidity and mortality. Gastroenterology 2016;150:1778-1785.
- Paik JM, Golabi P, Younossi Y, Mishra A, Younossi ZM. Changes in the Global Burden of Chronic Liver Diseases From 2012 to 2017: The Growing Impact of Nonalcoholic Fatty Liver Disease. Hepatology. 2020 Feb 11. doi: 10.1002/hep.31173. [Epub ahead of print].
- GBD 2017 Cirrhosis Collaborators. The global, regional, and national burden of cirrhosis by cause in 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet Gastroenterol Hepatol. 2020 Mar;5(3):245-266.