Bariatric intervention improves metabolic dysfunction-associated steatohepatitis in patients with obesity: A systematic review and meta-analysis

Abstract

Background/aims: Bariatric intervention has been reported to be an effective way to improve metabolic dysfunction-associated steatotic liver disease (MASLD) in obese individuals. The current systemic review aimed to assess the changes in MRI-determined hepatic proton density fat fraction (MRI-PDFF) and nonalcoholic fatty liver disease activity score (NAS) after bariatric surgery or intragastric balloon/gastric banding in MASLD patients with obesity.

Methods: We searched various databases including PubMed, OVID Medline, EMBASE, and Cochrane Library. Primary outcomes were the changes in intrahepatic fat on MRI-PDFF and histologic features of metabolic dysfunction-associated steatohepatitis (MASH).

Results: Thirty studies with a total of 3,134 patients were selected for meta-analysis. Bariatric intervention significantly reduced BMI (ratio of means, 0.79) and showed 72% reduction of intrahepatic fat on MRI-PDFF at 6 months after bariatric intervention (ratio of means, 0.28). Eight studies revealed that NAS was reduced by 60% at 3-6 months compared to baseline, 40% at 12-24 months, and 50% at 36-60 months. Nineteen studies revealed that the proportion of patients with steatosis decreased by 44% at 3-6 months, 37% at 12-24 months, and 29% at 36-60 months; lobular inflammation by 36% at 12-24 months and 51% at 36-60 months; ballooning degeneration by 38% at 12-24 months; significant fibrosis (≥F2) by 18% at 12-24 months and by 17% at 36-60 months after intervention.

Conclusion: Bariatric intervention significantly improved MRI-PDFF and histologic features of MASH in patients with obesity. Bariatric intervention might be the effective alternative treatment option for patients with MASLD who do not respond to lifestyle modification or medical treatment.

Keywords: Bariatric intervention; MASH; MRI-PDFF; NAS; Obesity.

Figure 1.

Flowchart of the study selection. Flowchart showing the process of study inclusion and exclusion in the systematic review. KMBASE, Korean Medical Database; KISS, Korean Studies Information Service System.

Figure 2.

Meta-analysis forest plot of BMI and histology. (A) BMI, (B) NAS by biopsy, (C) Steatosis, (D) Lobular inflammation, (E) Ballooning degeneration, and (F) Fibrosis (≥F2). (A) and (B): risk of means was reported. (C), (D), (E), and (F): proportion difference was reported. ^† and ^‡ indicate same cohort with different follow-up time frame. BMI, body mass index; NAS, nonalcoholic fatty liver disease activity score.

Figure 3.

Meta-analysis forest plot of BMI and MRI-PDFF. (A) BMI, and (B) Steatosis by MRI-PDFF. ^† and ^‡ indicate same cohort with different follow-up time frame. BMI, body mass index; MRI, magnetic resonance imaging; PDFF, proton density fat fraction.