Effectiveness of Bariatric Surgery for NAFLD/NASH

Inclusion Criteria:

[For Base-NAFLD]

1. Age between 16 and 65 years (all sexes).

2. Diagnosed with obesity according to the World Health Organization criteria forobesity in Asian populations and scheduled for a primary bariatric surgery at theparticipating centres.

3. Diagnosed with hepatic steatosis preoperatively by radiologic (includingultrasonography, magnetic resonance imaging [MRI]-derived proton density fatfraction [PDFF]) or pathologic(intraoperative hepatic pathology) examinations.

[For Base-NASH]

1. Age between 16 and 65 years (all sexes).

2. Diagnosed with obesity according to the World Health Organization criteria forobesity in Asian populations and scheduled for a primary bariatric surgery at theparticipating centres.

3. Histologically confirmed NASH with fibrosis:

NAFLD activity score(NAS) ≥4 with at least 1 in each single item and NASH-CRN fibrosis stage ≥F1

Exclusion Criteria:

• any patient who had previously been submitted to any type of bariatric surgery;

• history of excessive drinking: in the past 12 months, the male equivalent of alcoholconsumption more than 30g/d, and the female more than 20g/d;

• history of taking amiodarone, methotrexate, tamoxifen, glucocorticoids, etc.；

• history of specific diseases: Gene type 3 hepatitis C virus (HCV) infection,hepatolenticular degeneration, autoimmune hepatitis, total parenteral nutrition,lack of beta lipoproteinemia, congenital lipid atrophy, celiac disease which causingfatty liver, etc.;

• previous major gastrointestinal surgery；

• diagnosed or suspected malignancy；

• poorly controlled significant medical or psychiatric disorders；

• disorders such as a medical history of major pathology;

• can not be able to understand and willing to participate in this registry withsignature.