The global prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) is thought to be greater than 25%.[6]Duell PB, Welty FK, Miller M, et al; American Heart Association Council on Arteriosclerosis, Thrombosis and Vascular Biology; Council on Hypertension; Council on the Kidney in Cardiovascular Disease; Council on Lifestyle and Cardiometabolic Health; and Council on Peripheral Vascular Disease. Nonalcoholic fatty liver disease and cardiovascular risk: a scientific statement from the American Heart Association. Arterioscler Thromb Vasc Biol. 2022 Jun;42(6):e168-85.
https://www.ahajournals.org/doi/full/10.1161/ATV.0000000000000153
http://www.ncbi.nlm.nih.gov/pubmed/35418240?tool=bestpractice.com
Highest prevalence is in South Asia (33%), Middle East (32%), and South America (30%), and lowest prevalence is in Africa (13%).[6]Duell PB, Welty FK, Miller M, et al; American Heart Association Council on Arteriosclerosis, Thrombosis and Vascular Biology; Council on Hypertension; Council on the Kidney in Cardiovascular Disease; Council on Lifestyle and Cardiometabolic Health; and Council on Peripheral Vascular Disease. Nonalcoholic fatty liver disease and cardiovascular risk: a scientific statement from the American Heart Association. Arterioscler Thromb Vasc Biol. 2022 Jun;42(6):e168-85.
https://www.ahajournals.org/doi/full/10.1161/ATV.0000000000000153
http://www.ncbi.nlm.nih.gov/pubmed/35418240?tool=bestpractice.com
[7]Younossi ZM, Koenig AB, Abdelatif D, et al. Global epidemiology of nonalcoholic fatty liver disease-meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016 Jul;64(1):73-84.
https://www.doi.org/10.1002/hep.28431
http://www.ncbi.nlm.nih.gov/pubmed/26707365?tool=bestpractice.com
[8]Wong VW, Chan WK, Chitturi S, et al. Asia-Pacific working party on non-alcoholic fatty liver disease guidelines 2017 - part 1: definition, risk factors and assessment. J Gastroenterol Hepatol. 2018 Jan;33(1):70-85.
https://www.doi.org/10.1111/jgh.13857
http://www.ncbi.nlm.nih.gov/pubmed/28670712?tool=bestpractice.com
Prevalence increases with age.[7]Younossi ZM, Koenig AB, Abdelatif D, et al. Global epidemiology of nonalcoholic fatty liver disease-meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016 Jul;64(1):73-84.
https://www.doi.org/10.1002/hep.28431
http://www.ncbi.nlm.nih.gov/pubmed/26707365?tool=bestpractice.com
The median age at diagnosis is 53 years but the condition can occur at any age, including during childhood and adolescence.[9]Allen AM, Therneau TM, Larson JJ, et al. Nonalcoholic fatty liver disease incidence and impact on metabolic burden and death: a 20 year-community study. Hepatology. 2018 May;67(5):1726-36.
http://www.ncbi.nlm.nih.gov/pubmed/28941364?tool=bestpractice.com
[10]Vos MB, Abrams SH, Barlow SE, et al. NASPGHAN clinical practice guideline for the diagnosis and treatment of nonalcoholic fatty liver disease in children: recommendations from the Expert Committee on NAFLD (ECON) and the North American Society of Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN). J Pediatr Gastroenterol Nutr. 2017 Feb;64(2):319-34.
https://www.doi.org/10.1097/MPG.0000000000001482
http://www.ncbi.nlm.nih.gov/pubmed/28107283?tool=bestpractice.com
Between 1997 and 2014, cases of MASLD increased 7-fold in adults aged 18-39 years, 6-fold in adults aged 40-59 years, and 4-fold in adults aged 60 years and older.[9]Allen AM, Therneau TM, Larson JJ, et al. Nonalcoholic fatty liver disease incidence and impact on metabolic burden and death: a 20 year-community study. Hepatology. 2018 May;67(5):1726-36.
http://www.ncbi.nlm.nih.gov/pubmed/28941364?tool=bestpractice.com
Prevalence of suspected MASLD in US adolescents increased from 3.9% in 1988 to 1994 to 10.7% in 2007 to 2010.[11]Welsh JA, Karpen S, Vos MB. Increasing prevalence of nonalcoholic fatty liver disease among United States adolescents, 1988-1994 to 2007-2010. J Pediatr. 2013 Mar;162(3):496-500.e1.
http://www.ncbi.nlm.nih.gov/pubmed/23084707?tool=bestpractice.com
Men are more likely to be affected by MASLD than women.[12]Balakrishnan M. Women have a lower risk of nonalcoholic fatty liver disease but higher risk of nonalcoholic fatty liver disease fibrosis than men: summary of the findings of a systematic review and meta-analysis. Clin Liver Dis (Hoboken). 2021 Nov;18(5):251-4.
https://www.doi.org/10.1002/cld.1139
http://www.ncbi.nlm.nih.gov/pubmed/34840727?tool=bestpractice.com
[13]Shaheen M, Schrode KM, Pan D, et al. Sex-specific differences in the association between race/ethnicity and NAFLD among US population. Front Med (Lausanne). 2021;8:795421.
https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.795421/full
http://www.ncbi.nlm.nih.gov/pubmed/34926533?tool=bestpractice.com
Ethnic differences seem to play a role in the prevalence of fatty liver in the US, with Hispanic people more affected than white people.[11]Welsh JA, Karpen S, Vos MB. Increasing prevalence of nonalcoholic fatty liver disease among United States adolescents, 1988-1994 to 2007-2010. J Pediatr. 2013 Mar;162(3):496-500.e1.
http://www.ncbi.nlm.nih.gov/pubmed/23084707?tool=bestpractice.com
[13]Shaheen M, Schrode KM, Pan D, et al. Sex-specific differences in the association between race/ethnicity and NAFLD among US population. Front Med (Lausanne). 2021;8:795421.
https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.795421/full
http://www.ncbi.nlm.nih.gov/pubmed/34926533?tool=bestpractice.com
There is some evidence to suggest that African-Americans are less susceptible to the progressive form of the disease.[14]Sherif ZA, Saeed A, Ghavimi S, et al. Global epidemiology of nonalcoholic fatty liver disease and perspectives on US minority populations. Dig Dis Sci. 2016 May;61(5):1214-25.
http://www.ncbi.nlm.nih.gov/pubmed/27038448?tool=bestpractice.com
In England, the rates of premature death due to MASLD increased significantly in 2020 compared with 2019. The rate was 0.64 deaths per 100,000 population aged <75 years.[15]Office for Health Improvement and Disparities. Liver disease profiles: November 2021 update. Nov 2021 [internet publication].
https://www.gov.uk/government/statistics/liver-disease-profiles-november-2021-update/liver-disease-profiles-november-2021-update
The incidence and prevalence of metabolic dysfunction-associated steatohepatitis (MASH) is more difficult to ascertain because of the necessity of biopsy in order to make the diagnosis. Nearly 60% of people with MASLD who have a liver biopsy for a clinical indication have histological evidence of MASH.[7]Younossi ZM, Koenig AB, Abdelatif D, et al. Global epidemiology of nonalcoholic fatty liver disease-meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016 Jul;64(1):73-84.
https://www.doi.org/10.1002/hep.28431
http://www.ncbi.nlm.nih.gov/pubmed/26707365?tool=bestpractice.com
About 41% of patients with MASH have progressive liver fibrosis.[7]Younossi ZM, Koenig AB, Abdelatif D, et al. Global epidemiology of nonalcoholic fatty liver disease-meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016 Jul;64(1):73-84.
https://www.doi.org/10.1002/hep.28431
http://www.ncbi.nlm.nih.gov/pubmed/26707365?tool=bestpractice.com
Advanced (stages 3 and 4) fibrosis in MASH is associated with increased liver-related complications and death.[16]Sanyal AJ, Van Natta ML, Clark J, et al. Prospective study of outcomes in adults with nonalcoholic fatty liver disease. N Engl J Med. 2021 Oct 21;385(17):1559-69.
http://www.ncbi.nlm.nih.gov/pubmed/34670043?tool=bestpractice.com