Comparison of MAFLD and NAFLD Characteristics in Children

Abstract

Background & aims: An international panel proposed a diagnostic framework for metabolic-associated fatty liver disease (MAFLD) in children. The aim was to compare the clinical features of MAFLD and nonalcoholic fatty liver disease (NAFLD) in children.

Methods: The characteristic differences between NAFLD and MAFLD in children were compared with the National Health and Nutrition Examination Survey (NHANES) 2017-2018 in the U.S. and the Comprehensive Prevention Project for Overweight and Obese Adolescents (CPOOA) study in China.

Results: In NHANES 2017-2018, regardless of which criteria were implemented, participants with hepatic steatosis were more likely to have higher BMI z-scores, a higher prevalence of hypertension or higher metabolic indices and higher non-invasive liver fibrosis scores (all p < 0.05). The cases diagnosed by those two definitions had a similarity of over 75%. More obese children were diagnosed with MAFLD than NAFLD (p < 0.001). However, approximately 19% of children with NAFLD present with normal weight and fasting glucose levels and cannot be diagnosed with MAFLD. The CPOOA study excluded viral infected liver disease and certain kinds of congenital causes of liver steatosis patients, resulting in children with NAFLD being identical with MAFLD children.

Conclusions: Most clinical features were similar between children with MAFLD and children with NAFLD, and more than 75% of children with NAFLD can also be diagnosed with MAFLD. However, approximately 19% of children with NAFLD cannot be categorized as MAFLD. Therefore, to gain greater benefits from renaming NAFLD to MAFLD in pediatrics, the prevalence of different causes of hepatic steatosis in children needs to be understood.

Keywords: CPOOA; NHANES; hepatic steatosis; metabolic-associated fatty liver disease; nonalcoholic fatty liver disease.

Figure 1

Flow chart of case selection in NHANES 2017–2018. The diagnosis of metabolic-associated fatty liver disease (MAFLD) is shown on the left. Participants with a positive diagnosis of hepatic steatosis who could not be diagnosed with MAFLD or non-MAFLD due to the omission of other indicators were classified as “Unable to diagnose”. The diagnosis of nonalcoholic fatty liver disease (NAFLD) is shown on the right. HBV, hepatitis B virus; HCV, hepatitis C virus.

Figure 2

Characteristic composition of NAFLD participants (a) and MAFLD participants (b) in NHANES 2017–2018 and CPOOA. US and China correspond to the 2017–2018 National Health and Nutrition Examination Survey (NHANES) and the Comprehensive Prevention Project for Overweight and Obese Adolescents (CPOOA), respectively. (a,b) show the etiological composition of participants with metabolic-associated fatty liver disease (MAFLD) and participants with nonalcoholic fatty liver disease (NAFLD) in the two studies, respectively. Dark blue indicates the presence of the factor OWOB only, orange indicates the presence of both OWOB and metabolic dysregulation, grey indicates the presence of both OWOB and prediabetes or type 2 diabetes, yellow indicates the presence of all three factors: OWOB, metabolic dysregulation and prediabetes or type 2 diabetes, and light blue indicates the presence of only one factor: prediabetes or type 2 diabetes. Green means none of the above three factors were present. OWOB, overweight/obesity.

Figure 3

Composition of MAFLD and NAFLD in NHANES 2017–2018. The blue circle indicates participants with metabolic-associated fatty liver disease (MAFLD), and the green circle indicates participants with nonalcoholic fatty liver disease (NAFLD); the middle overlapping part indicates participants with both MAFLD and NAFLD.

Figure 4

The relationship between MAFLD and NAFLD (wheel model). The inner circle represents nonalcoholic fatty liver disease (NAFLD), and the outer circle represents metabolic-associated fatty liver disease (MAFLD). The four colors indicate infections, dietary causes, medications and genetic/metabolic disorders.