Prevalence of NAFLD, MAFLD and Associated Advanced Fibrosis in the Contemporary United States Population

Stefano Ciardullo; Gianluca Perseghin


Liver International. 2021;41(6):1290-1293. 

In This Article


The studied population consisted in 1710 participants. Mean age was 46.4 years (95% confidence interval [CI] 44.8–48.0) and 48.6% were male. As shown in Figure 1, weighted prevalence of NAFLD and MAFLD were similar in the whole population at 37.1% (95% CI 34.0–40.4) and 39.1% (95% CI 36.3–42.1) respectively. Prevalence was highest among Hispanics (43.9% for NAFLD and 46.7% for MAFLD) and lowest among non-Hispanic blacks (29.6% for NAFLD and 31.8% for MAFLD). Overall agreement between the two definitions was 96.1% and Cohen's κ was 0.92. Prevalence of NAFLD and MAFLD according to race-ethnicity using different cut-offs are shown in Table S1. Only 13 patients with NAFLD did not meet MAFLD criteria (2.7%, 95% CI 1.4–5.2). None of them had evidence of advanced fibrosis. Conversely, 54 patients with MAFLD did not meet NAFLD criteria (7.6%, 95% CI 4.4–12.9), mainly because of significant alcohol consumption and viral hepatitis. Advanced fibrosis in this subgroup was similar to the overall estimate (Table 1). Prevalence of advanced liver fibrosis among patients with NAFLD and MAFLD was 7.5% (95% CI 4.9–11.4) and 7.4% (95% CI 4.9–11.4) respectively. Similar to steatosis, it was highest among Hispanics and lowest among non-Hispanic blacks.

Figure 1.

Weighted prevalence of NAFLD, MAFLD and associated advanced fibrosis by race/ethnicity in US adults. (A) Prevalence of NAFLD and MAFLD diagnosed according to a Controlled Attenuation Parameter ≥ 274 dB/m (B) Prevalence of advanced fibrosis diagnosed according to liver stiffness measurement ≥ 9.7 KPa in subjects with NAFLD and MAFLD. Abbreviations: NHW, non-Hispanic white; NHB, non-Hispanic black; NHA, non-Hispanic Asian