Mid-term Effects of Bariatric Surgery on Metabolic Dysfunction-Associated Fatty Liver Disease Remission and Predictive Factors: A Prospective Study with a Focus on Non-invasive Diagnosis

Post-Metabolic Bariatric Surgery Cirrhosis and the Role of Liver Transplantation: A Report from a Referral Transplant Center

BACKGROUND

Despite their benefits, metabolic bariatric surgery (MBS) has been associated with rare but severe complications, including liver failure (LF) and the need for orthotopic liver transplantation (OLT). The exact mechanisms underlying MBS-related cirrhosis remain unclear, and comprehensive data on this topic are scarce.

METHOD

This retrospective study analyzed 10 patients who underwent OLT after MBS due to decompensated LF. Demographic, clinical, and laboratory data were collected and analyzed, including pre- and post-MBS body mass indexes (BMI), liver function tests, and MELD scores.

RESULTS

Mean age was 42.9 years with the female percentage of 40%. Except for two patients who had 110 and 120 months between the MBS and OLT, remaining eight cases had a mean 19.6 months interval between the MBS and OLT. Roux-en-Y gastric bypass (RYGB) being the most common procedures, two of them reported consumption of alcohol, one died afterwards. Four patients died due to different reasons through the study (Two sleeve (SG), and one for each RYGB and one-anastomosis gastric bypass). There were significant correlations between overall survival (OS) and age (Spearman's rank correlation coefficient (r) = 0.85, p = 0.002), bilirubin (r = - 0.74, p = 0.013), and MELD score (r = - 0.69, p = 0.026). Survival with log rank test was only significant for MBS types (p = 0.035). COX regression was significant when compare RYGB vs. SG (Exp(B) = 0.069, p = 0.048).

CONCLUSION

MBS-related cirrhosis is rare but potentially life-threatening and OLT is the final step with a noticeable risk of mortality. Comprehensive preoperative liver assessment, careful selection of MBS procedures, and close postoperative monitoring are crucial for mitigating risks.

Short-Term Evolution of MASLD Following Roux-en-Y Gastric Bypass: A Focus on Fibrotic MASH

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) includes simple steatosis and metabolic dysfuncion-associated steatohepatitis (MASH), with fibrosis in MASH serving as a critical prognostic marker. This study investigates the effects of Roux-en-Y gastric bypass (RYGB) on fibrotic MASH, assessed using the fibrotic NASH index (FNI) and the non-invasive NASH detection score (NI-NASH-DS), as well as provides further data on the diagnostic accuracy of both scores.

METHODS

A retrospective cohort study was conducted involving 104 individuals (91.3% female, mean age 39.4 ± 8.6 years) who underwent RYGB. Histopathological evaluations during surgery identified fibrotic MASH, and FNI and NI-NASH-DS values were calculated at baseline and 1 year post-surgery.

RESULTS

At the time of surgery, participants had a mean BMI of 35.3 ± 2.8 kg/m2, which decreased to 27.1 ± 4.0 kg/m2 1 year after surgery. The mean % total weight loss (%TWL) was 23.8 ± 10.1%, and the mean % excess weight loss (%EWL) was 82.4 ± 37.3%. Fibrotic MASH was present in 17.3% of participants pre-operatively. The mean FNI score significantly decreased after surgery (p < 0.0001). Female gender (p < 0.001) and histological evidence of lobular inflammation (p < 0.001) were independently associated with the improvement of FNI. The FNI demonstrated high diagnostic accuracy (sensitivity: 61.1%, specificity: 96.4%, overall accuracy: 90.2%). NI-NASH-DS had a 60% accuracy in detecting MASH, alongside an 85.9% specificity.

CONCLUSIONS

RYGB seemingly promotes improvement of fibrotic MASH as evaluated by FNI, highlighting its potential as a therapeutic intervention to mitigate MASLD progression. Both FNI and NI-NASH-DS are helpful and inexpensive tools for assessing MASH.

Decreased liver volume after bariatric surgery and its positive impact on liver function tests and lipid profile

BACKGROUND

Obesity is associated with a higher incidence of fatty liver disease, intrahepatic triglyceride content, and hepatic fibrosis. These abnormalities could progress to severe liver disease.

OBJECTIVES

To evaluate the effects of bariatric surgery (BaS)-induced weight loss on liver volume, hepatic function tests, and lipid profile.

SETTING

Academic Hospital, United States.

METHODS

We conducted a retrospective review of an institutional review board (IRB)-approved database on patients who underwent BaS from 2006 to 2018. To determine changes in liver volume, we reviewed abdominal computed tomography scans before BaS (Group 1) and up to 18 months after (Group 2). Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lipid profiles were collected before and after BaS.

RESULTS

Seventy-three patients met the inclusion criteria. Patients were predominantly females 78.1% (57), with an average age of 51.29+12.54 years. The liver volume was 1870.73 + 638.5 mm3 before and 1555.15 + 464.8 after BaS (P = .004). ALT was 36.9 + 25.3 before versus 23.8 + 19.3 after BaS (P = .024).Triglyceride levels changed from 135.62 + 69.98 before to 97.50 + 47.33 after BaS (P = .009). Low-density lipoprotein decreased from 107.9 + 38.1 to 89.6 + 32.8 (P = .048).

CONCLUSIONS

BaS-induced weight loss determines significant liver shrinkage by reducing liver volume, and coincides with improvements in hepatic function tests and lipid profile. Our results suggest that BaS might contribute to reduction of the progression of fatty liver disease to fibrosis.

Metabolic Dysfunction-Associated Steatotic Liver Disease in Severe Obesity and Concordance between Invasive (Biopsy) and Noninvasive (OWLiver®) Diagnoses

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD), now termed metabolic dysfunction-associated steatotic liver disease (MASLD), is an escalating health concern linked to obesity and type 2 diabetes. Despite liver biopsy being the gold standard, its invasiveness underscores the need for noninvasive diagnostic methods.

METHODS

A cross-sectional study was performed to assess MASLD using the noninvasive OWLiver® serum lipidomics test in a cohort of 117 patients with severe obesity undergoing bariatric surgery, comparing outcomes with liver biopsy. Exclusions (n = 24) included insufficient data, liver disease etiology other than MASLD, corticosteroid treatment, excessive alcohol consumption, low glomerular filtration rate, and declination to participate. Comprehensive laboratory tests, demographic assessments, and liver biopsies were performed. Serum metabolites were analyzed using OWLiver®, a serum lipidomic test that discriminates between healthy liver, steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and MASH with fibrosis ≥2 by means of three algorithms run sequentially.

RESULTS

Liver biopsy revealed a MASLD prevalence of 95.7%, with MASH present in 28.2% of cases. OWLiver® demonstrated a tendency to diagnose more severe cases. Body mass index (BMI), rather than the presence of type 2 diabetes, emerged as the sole independent factor linked to the probability of concordance. Therefore, the all-population concordance of 63.2% between OWLiver® and liver biopsy notably raised to 77.1% in patients with a BMI <40 kg/m2. These findings suggest a potential correlation between lower BMI and enhanced concordance between OWLiver® and biopsy.

CONCLUSION

This study yields valuable insights into the concordance between liver biopsy and the noninvasive serum lipidomic test, OWLiver®, in severe obesity. OWLiver® demonstrated a tendency to amplify MASLD severity, with BMI values influencing concordance. Patients with BMI <40 kg/m2 may derive optimal benefits from this noninvasive diagnostic approach.

Underlying Mechanisms behind the Brain-Gut-Liver Axis and Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Metabolic-associated fatty liver disease (MAFLD) includes several metabolic dysfunctions caused by dysregulation in the brain-gut-liver axis and, consequently, increases cardiovascular risks and fatty liver dysfunction. In MAFLD, type 2 diabetes mellitus, obesity, and metabolic syndrome are frequently present; these conditions are related to liver lipogenesis and systemic inflammation. This study aimed to review the connection between the brain-gut-liver axis and MAFLD. The inflammatory process, cellular alterations in hepatocytes and stellate cells, hypercaloric diet, and sedentarism aggravate the prognosis of patients with MAFLD. Thus, to understand the modulation of the physiopathology of MAFLD, it is necessary to include the organokines involved in this process (adipokines, myokines, osteokines, and hepatokines) and their clinical relevance to project future perspectives of this condition and bring to light new possibilities in therapeutic approaches. Adipokines are responsible for the activation of distinct cellular signaling in different tissues, such as insulin and pro-inflammatory cytokines, which is important for balancing substances to avoid MAFLD and its progression. Myokines improve the quantity and quality of adipose tissues, contributing to avoiding the development of MAFLD. Finally, hepatokines are decisive in improving or not improving the progression of this disease through the regulation of pro-inflammatory and anti-inflammatory organokines.