Table 2.

Summary of included studies assessing NAFLD outcomes.

Author, Year	Period Country	Design and population	Diagnosis method	Outcomes	Axes of Inequality	Results	Conclusions	Limitations
Noureddin, 2018 [6]	2004–2016 US	Study cohort logistic Regression DB: UNOS/OPTN n = 127,164 Age ≥ 18	Not specified	COMP (LT) and AdLD (NASH)	Sex Ethnicity	NASH was the leading cause of LT for women and the 2nd leading cause for men (following alcoholic liver disease). NASH increased as the cause in all ethnic subgroups and was the leading cause in 2016 among Asian, Hispanic, and non-Hispanic white females.	NASH is the second leading cause for LT waitlist registration/LT and in females, the leading cause. NASH will rise to become the leading indication for LT in males	Includes other liver diseases.
Younossi, 2012 [23]	1988–1994 US	Cross-sectional study DB: NHANES III n = 11,613 Age ≥ 20	Ultrasound	AdLD (NASH)	Ethnicity	NASH is independently associated with being Hispanic (OR 1.72; 95% CI 1.28–2.33) and less associated with being African American (OR 0.52, 95% CI 0.34–0.78).	Patients with NASH are commonly Hispanic and less likely to be African American.	Does not perform an intersectional analysis.
Williams, 2011 [26]	2007–2010 US	Prospective Brooke army medical center n = 328 (156 positive US) Age 28–70	Ultrasound and optional liver biopsy	AdLD (NASH)	Ethnicity Sex	NASH prevalence: Hispanics 19.4% > Caucasians 9.8% (p = 0.03) NASH has a prevalence of 22.2% in the diabetic population. NASH patients are predominantly male (65%).	NASH prevalence is higher than estimated. Hispanics and patients with diabetes are at the greatest risk for NASH.	Does not perform an intersectional analysis.
Wu, 2018 [37]	1993–2017 US	Retrospective analysis Medical records. n = 1206 Age ≥ 18	Histologically (biopsy at surgery), imaging (CT and MRI) and AFP	COMP (HCC)	Sex	Females develop HCC at a significantly older age (66 years vs. 61.6 years, p < 0.001). Elderly females (≥65 years) are more likely than elderly males to have NAFLD/NASH-related HCC (28.0% vs. 14.8%, p = 0.0006).	Older females with HCC have more NAFLD/NASH and may be overlooked by current surveillance guidelines.	Includes other liver diseases. Does not perform an intersectional analysis.
Adejumo, 2019 [32]	2007–2014 US	Retrospective cross-sectional study DB: HCUP-NIS n = 210,660 Age	ICD-9 NIS does not contain information on how NAFLD was diagnosed	COMP (hospitalization and mortality) AdLD (cirrhosis)	Sex Ethnicity SES	Females had a 5% shorter LOS than males (4.35 [95% CI, 4.26–4.45] vs. 4.18 [95% CI 4.08–4.27]; p < 0.0001) and 10% lower odds of mortality (AOR 0.91, 95% CI 0.83–0.99; p = 0.03). African American had a 7% longer LOS than Whites (4.48 [95% CI 4.34–4.62] vs. 4.20 [95% CI 4.11–4.29] days; p < 0.0001); and 14% greater odds of unfavorable discharge compared with Whites (AOR 1.14, 95% CI 1.06–1.22; p < 0.0001). Non-private insured patients had 14% higher mortality than those with private insurance (AOR 1.14, 95% CI 1.09–1.67; p = 0.002). Females had a higher frequency of compensated (2.39% vs. 1.93%) and decompensated (2.80% vs. 2.31%) cirrhosis.	Males, Hispanics, individuals with non-private health insurance are disproportionately affected, with higher NAFLD complications.	Does not perform an intersectional analysis.
Golovaty, 2020 [33]	2005–2014 US	Cross-sectional analysis DB: NHANES n = 2627 of low-income adults Age ≥ 20	NAFLD fibrosis score (NFS) for advanced liver fibrosis	AdLD (advanced fibrosis)	SES (Food Insecurity)	A total of 29% (95% CI: 26%, 32%) were food-insecure. Multivariable model: food-insecure adults are more likely to have advanced (adjusted OR 2.20; 95% CI: 1.27–3.82).	Food insecurity may be independently associated with NAFLD and advanced fibrosis among low-income adults in the US.	Does not perform an intersectional analysis.
Zhang, 2021 [38]	1990–2017 Global	Retrospective analysis DB: GBD study, 2017	Not specified	AdLD (NASH, cirrhosis)COMP (liver cancer)	Sex SES	The global DALYs numbers of liver cancer due to NASH were negatively associated with SDI levels (r = −0.409, p < 0.001). The global prevalence number of liver cancer due to NASH peaked at 60–64 years in males and 65–69 years in females. Globally, the burden was heavier in males compared with females. In groups > 70 years, the DALYs in females for cirrhosis started to be higher than in males.	The global burden of NASH-associated liver cancer has increased significantly since 1990, with age, sex, and geographic disparity.	The accuracy of the GBD estimates was limited by the quality and availability of original hospital and claims data.
Mazumder, 2020 [39]	2006–2012 US	Retrospective analysis DB: OPTN n = 20,045 Age ≥ 18	Not specified	COMP (mortality, LT) AdLD (NASH, cirrhosis)	Sex	Females had higher rates of NASH (29.8% vs. 21.2%, p < 0.001) than males. Although lower rates of listing (7.5% vs. 9.8%; p < 0.001) and LT (3.5% vs. 5.2%; p < 0.001) among women, no significant difference was noted for either all-cause mortality (sHR 1.09; 95% CI 0.88–1.35) or liver-related death (sHR 1.12; 95% CI 0.87–1.43). Females had higher rates of NASH-related cirrhosis (29.8% vs. 21.2% p < 0.001)	In patients with cirrhosis, women were not at an increased risk of liver-related death despite lower rates of listing and transplantation.	Does not perform an intersectional analysis.
Yang, 2014 [40]	2007–2010 US	Cross-sectional study DB: DUHS NAFLD Clinical DB n = 203 Age ≥ 18	Liver biopsy	AdLD (advanced fibrosis)	Sex Ethnicity	The likelihood for greater fibrosis severity was ACOR: 1.4 (95% CI 0.9–2.1, p = 0.17) for PMP women and ACOR 1.6 for men (95% CI 1.0–2.5, p = 0.03), with premenopausal women as a reference. Before age 50, men had a higher risk of having greater severity of fibrosis than women ACOR 1.8 (95% CI, 1.1–2.9, p = 0.02). After age 50, the protective effect observed in women appeared to be eliminated (ACOR 1.2, 95% CI 0.7–2.1, p = 0.59). Age ≥ 50 was associated with an increased risk of having more advanced fibrosis only among women (ACOR 1.8, 95% CI 1.2–2.7, p < 0.01)	Men are at a higher risk of having more severe fibrosis compared to women before menopause, while postmenopausal women have a similar severity of liver fibrosis compared to men.	Does not perform an intersectional analysis. Purely biological approach.
Phipps, 2020 [41]	2000–2014 US	Multicenter retrospective study Hospital centers n = 5327Age ≥ 18	Imaging or biopsy	COMP (HCC)	Sex	Among patients with HCC, NAFLD was the underlying etiology of liver disease in 23.3% of cases compared with 12.4% of men.	The frequency of underlying NAFLD was significantly higher in women than men.	They do not classify women as pre/PMP. Includes other liver diseases.
Loy, 2018 [42]	2005–2012 US	Retrospective study with an 8-year follow-up DB UNOS/STAR n = 76,149	Not specified	COMP (LT and mortality)	Sex	NASH is a more frequent indication for LT listing in women than men. LT is lower among women than men with NASH (52.4% vs. 64.3%), and women are more likely to experience death on the WL (17.1% vs. 11.4%). In multivariable analysis adjusting for covariates, the rate of LT remained lower for women with NASH (aHR 0.81 95% CI 0.75–0.88).	Women with NASH cirrhosis had a higher risk of death on the LT waiting list and were less likely to receive LT compared to men.	Does not perform an intersectional analysis.
Ochoa, 2020 [43]	2002–2013 US	Retrospective analysis DB: UNOS/OPTN n = 45,767 Age ≥ 18	Not specified	COMP (mortality, LT)	Ethnicity	Non-Hispanic whites are more commonly transplanted for NASH than Hispanics. Hispanics had a decreased risk of death when transplanted for NASH (HR 0.84, 95% CI 0.71–0.99; p = 0.04).	Hispanics have similar or better long-term post-LT outcomes compared to non-Hispanic whites despite a worse pretransplant risk factor profile.	Only analyzes Hispanics and non-Hispanic Whites.

Footnote: ACOR (adjusted cumulative odds ratio), AFP (alpha-fetoprotein), aHR (adjusted hazard ratio), AdLD (advanced liver disease), AOR (adjusted odds ratio), CI (confidence interval), COMP (complications), CT (computed tomography), DALYs (disability-adjusted life years), DB (database), DUHS (Duke University Health System), GBD (global burden of disease), HCC (hepatocellular carcinoma), HCUP (Healthcare Cost and Utilization Project), HR (hazard ratio), ICD-9 (international classification of disease), LOS (length of stay), LT (liver transplant), M (men), MRI (magnetic resonance imaging), NAFLD (non-alcoholic fatty liver disease), NASH (non-alcoholic steatohepatitis), NIS (national inpatient survey), NHANES (national health and nutrition examination survey), OPTN (Organ Procurement and Transplantation Network), OR (odds ratio), PMP (postmenopausal), RF (risk factor), SDI (sociodemographic index), SES (socioeconomic status/position), sHR (subdistribution hazard ratio), STAR (Standard Transplant Analysis and Research), UNOS (United Network for Organ Sharing), W (women), WL (waitlist).