Effects of Roux-en-Y Gastric Bypass and Sleeve Gastrectomy on Non-Alcoholic Fatty Liver Disease: A 12-Month Follow-Up Study with Paired Liver Biopsies

Roux-en-Y gastric bypass (RYGB) improves, and can sometimes resolve, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) but data based on histological assessment for the efficacy of sleeve gastrectomy (SG) in resolving NAFLD are sparse. Consequently, we aimed to compare the efficacy of RYGB vs. SG on NAFLD 12 months after surgery. In a prospective cohort study, 40 patients with obesity underwent bariatric surgery (16 RYGB and 24 SG). During surgery, a liver biopsy was taken and repeated 12 months later. NAFLD severity was evaluated using the NAFLD Activity Score (NAS) and Kleiner Fibrosis score. RYGB and SG patients were comparable at baseline. Mean (standard deviation, SD) NAS was 3.3 (0.9) in RYGB and 3.1 (1.4) in SG (p = 0.560) with similar degrees of steatosis, inflammation, and ballooning. Two RYGB patients, and six SG patients, had NASH (p = 0.439). Twelve months after surgery, NAS was significantly and comparably (p = 0.241) reduced in both RYGB (−3.00 (95% CI −3.79–−2.21), p < 0.001) and SG (−2.25 (95% CI −2.92–−1.59), p < 0.001) patients. RYGB patients had significantly more reduced (p = 0.007) liver steatosis (−0.91 (95% CI −1.47–−1.2) than SG patients (−0.33 (95% CI −0.54–−0.13) and greater improvement in the plasma lipid profile. Fibrosis declined non-significantly. NASH was resolved in seven of eight patients without a worsening of their fibrosis. RYGB and SG have similar beneficial effects on NAS and NASH without the worsening of fibrosis. RYGB is associated with a more pronounced reduction in liver steatosis.

Diagnostic accuracy of FibroScan-AST score to identify non-alcoholic steatohepatitis with significant activity and fibrosis in Japanese patients with non-alcoholic fatty liver disease: Comparison between M and XL probes

AIM

Recently, FibroScan-AST (FAST) score was reported to be effective for identifying non-alcoholic steatohepatitis (NASH) with significant activity and fibrosis in non-alcoholic fatty liver disease (NAFLD). The aim of this study was to confirm the diagnostic accuracy of FAST score of Japanese patients and compare the cut-off values and diagnostic accuracy between the FibroScan M and XL probes.

METHODS

Eighty-two and 84 patients were included the verification and validation sets, respectively. All patients were diagnosed with NAFLD by biopsy by two central expert pathologists. Liver stiffness measurements and controlled attenuation parameter were carried out, and diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

No significant difference existed in FAST score between the M and XL probes (0.489 vs. 0.483, P = 0.187). No significant difference existed in the area under the ROC between the two probes (M, 0.7598; XL, 0.7614; P = 0.958). According to the Youden index, the cut-off value using the M probe was 0.57 with 68.2% sensitivity and 78.3% specificity. For the XL probe, the cut-off value was 0.56 with 68.2% sensitivity and 73.3% specificity. To obtain sensitivity and specificity values higher than 90%, cut-off values of 0.35 and 0.66 were chosen for the M probe and 0.32 and 0.63 were chosen for the XL probe.

CONCLUSIONS

There was no significant difference in diagnostic accuracy of FAST score between the FibroScan M and XL probes. The FAST score can be used to identify NASH with significant risk in Japanese patients regardless of probe selection.