Ethnic and Sex Differences in Fatty Liver on Cardiac Computed Tomography: The Multi-Ethnic Study of Atherosclerosis

Abstract

Objective To describe ethnic and gender differences in the prevalence and determinants of fatty liver in a multi-ethnic cohort. Patients and Methods We studied participants from the Multi-Ethnic Study of Atherosclerosis who underwent baseline non-contrast cardiac CT between July 2000-August 2002, and had adequate hepatic and splenic imaging for fatty liver determination (n=4088). Fatty liver was diagnosed by a liver/spleen attenuation ratio <1. We compared the prevalence and severity of fatty liver, among four ethnicities (White, Chinese, African American, Hispanic), stratifying by obesity and metabolic syndrome. Multivariable ordinal logistic regression was employed to determine the impact of cardio-metabolic risk factors on fatty liver prevalence in different ethnicities. Results The prevalence of fatty liver varied significantly by ethnicity (White 15%, Chinese 20%, African-American 11%, Hispanic 27%, p<0.001). Although African-Americans had the highest prevalence of obesity, a smaller percentage of obese African Americans were diagnosed with fatty liver compared to other ethnicities (African American 17%, White 31%, Chinese 37%, Hispanic 39%, p<0.001). Hispanics demonstrated the highest prevalence of fatty liver, including among the obese and metabolic syndrome population. An increase in insulin resistance predicted a two-fold increased prevalence of fatty liver in all ethnicities after multi-variable adjustment. Conclusion African-Americans have a lower prevalence, and Hispanic Americans a higher prevalence of fatty liver compared to other ethnicities. There are distinct ethnic variations in the prevalence of fatty liver even among patients with the metabolic syndrome or obesity, suggesting that genetic factors may play a significant role in the phenotypic expression of fatty liver.

Heart Disease and Stroke Statistics—2017 Update: A Report From the American Heart Association

“…For example, in community-based US data from the 2000 to 2002 MESA study participants, nonalcoholic fatty liver disease was present in 17% of African Americans with metabolic syndrome but was present in 39% of Hispanics with metabolic syndrome. 23 The phenotypic expression of metabolic syndrome also varies by country and culture, particularly in Europe. 24 …”

Cardiometabolic Abnormalities Among Normal-Weight Persons From Five Racial/Ethnic Groups in the United States

“…Noncontrast cardiac CT images were obtained with a cardiac-gated CT scanner (Phillips 16D or Toshiba MSD Aquillion 64 at the University of California, San Francisco, and Siemens Sensation Cardiac 64 at Northwestern University) to assess pericardial fat volume and hepatic fat attenuation. Measurement methods and reading centers were similar to those used in MESA (20). …”

Epidemiological modifiers of non-alcoholic fatty liver disease: Focus on high-risk groups

“…[44][45][46][47] Whether sex affects NAFLD natural history and mortality is uncertain, although studies have suggested a worse outcome in men. 45,48,49 The prevalence of NAFLD follows a gradient Hispanics >Whites-Caucasians >Afro-Americans [50][51][52][53] and ethnicity may modulate the association between NAFLD, sex and MetS features. For example, NAFLD is more common in men than in women among Whites, but not among Blacks or Hispanics.…”

“…In contrast, Hispanics have the highest prevalence of NAFLD, including the obese and MetS population. 53 Interestingly, among patients with NAFLD, African Americans have NASH less frequently than…”