EPIDEMIOLOGY

THE RISING CLINICAL AND ECONOMIC BURDEN OF NAFLD/NASH

In 2021, it is estimated that 25% of the global adult population is potentially affected by non-alcoholic fatty liver disease (NAFLD), with the highest prevalence in the Middle East (31,8%) and South America (30,5%) and the lowest in Africa (13,5%). A recent study by Harrison et al. used a combination of state-of-the-art liver imaging methods and liver biopsy to prospectively determine the prevalence of NAFLD and NASH in asymptomatic middle-aged Americans. In this study, the prevalence of NAFLD was 38% (95% CI 34-41%) and the prevalence of NASH was 14% (95% CI 12-17%).

SPECIAL POPULATIONS

There is a significant racial disparity in the prevalence of NAFLD in the United States. A systematic review and meta-analysis by Rich et al. in 2018, showed significant racial disparities in NAFLD prevalence and severity in the United States, with NAFLD prevalence being highest in Hispanics, intermediate in Whites, and lowest in Blacks. Among patients with NAFLD, risk for progression to NASH was higher in Hispanics and lower in Blacks than in Whites. However, the proportion of patients with significant fibrosis did not significantly differ among racial groups. A study of etiology-based and ethnicity-based annual mortality rates of cirrhosis and hepatocellular carcinoma (HCC) in the United State by Kim et al. showed that the mortality rates for NAFLD-cirrhosis and HCC have increased in non-Hispanic whites followed by Hispanics and non-Hispanic blacks.

Furthermore, the prevalence of NAFLD among children and adolescents is increasing, affecting approximately 3% to 10% of all children and over one-third of obese children in developed countries. The increasing prevalence of NAFLD is linked to a rise in other non-communicable diseases such as type-2 diabetes mellitus (T2DM), obesity and cardiovascular disease (CVD), which are primarily related to unhealthy lifestyles and diet. However, ageing and genetics might also play an important role, particularly in Native American and Hispanic populations.

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Adapted from : Younossi ZM, Koenig AB, Abdelatif D, Fazel Y, Henry L, Wymer M. Global epidemiology of nonalcoholic fatty liver disease-Meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016 Jul;64(1):73-8

  1. Ando Y, Jou JH. Nonalcoholic fatty liver disease and recent guideline updates. Clin Liver Dis (Hoboken). 2021; 17:23-28.
  2. Chalasani N, Younossi Z, Lavine JE, et al. The diagnosis and management of nonalcoholic fatty liver disease: Practice guidance from the American Association for the Study of Liver Diseases. Hepatology. 2018;67:328-57.
  3. EASL-EASD-EASO Clinical Practice Guidelines for the management of non-alcoholic fatty liver disease. J Hepatol. 2016;64:1388-402.
  4. Harrison SA, Gawrieh S, Roberts K, et al. Prospective evaluation of the prevalence of non-alcoholic fatty liver disease and steatohepatitis in a large middle-aged US cohort. J Hepatol. 2021;75(2):284-291.
  5. Huang DQ, El-Serag HB, Loomba R. Global epidemiology of NAFLD-related HCC: trends, predictions, risk factors and prevention. Nat Rev Gastroenterol Hepatol.2021 Apr;18(4):223-238.
  6. Kim D, Li AA, Perumpail BJ, et al. Changing trends in etiology-based and ethnicity-based annual mortality rates of cirrhosis and hepatocellular carcinoma in the United States. Hepatology 2019;69:1064-1074.
  7. Ray K. Examining the prevalence of NAFLD and NASH in a US cohort. Nat Rev Gastroenterol Hepatol. 2021 May;18(5):286.
  8. Rich NE, Oji S, Mufti AR, et al. Racial and ethnic disparities in nonalcoholic fatty liver disease prevalence, severity, and outcomes in the United States: A systematic review and meta-analysis. Clin Gastroenterol Hepatol 2018;16:198-210.e2.
  9. Schattenberg JM, Lazarus JV, Newsome PN, et al. Disease burden and economic impact of diagnosed non-alcoholic steatohepatitis in five European countries in 2018: A cost-of-illness analysis. Liver Int. 2021 Jun;41(6):1227-1242.
  10. Sheka AC, Adeyi O, Thompson J, et al. Nonalcoholic Steatohepatitis: A Review. JAMA. 2020 Mar 24;323(12):1175-1183.
  11. Stefan N, Häring HU, Cusi K. Non-alcoholic fatty liver disease: causes, diagnosis, cardiometabolic consequences, and treatment strategies. Lancet Diabetes Endocrinol. 2019 Apr;7(4):313-324.
  12. Younossi ZM, Koenig AB, Abdelatif D, Fazel Y, Henry L, Wymer M. Global epidemiology of nonalcoholic fatty liver disease – Meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016;64:73-84.
  13. Younossi ZM. Non-alcoholic fatty liver disease – A global public health perspective. J 2019 Mar;70(3):531-544.
  14. Younossi Z, Tacke F, Arrese M, et al. Global perspectives on non-alcoholic fatty liver disease and non-alcoholic steatohepatitis. 2019 Jun;69(6):2672-2682.