Are Noninvasive Methods Comparable to Liver Biopsy in Postoperative Patients After Roux-en-Y Gastric Bypass?

Protocol of quantitative ultrasound techniques for noninvasive assessing of hepatic steatosis after bariatric surgery

Introduction

Roux-en-Y gastric bypass surgery can effectively improve steatosis, necroinflammatory activity, and hepatic fibrosis in individuals diagnosed with morbid obesity or nonalcoholic steatohepatitis (NASH). Common methods such as body mass index (BMI) to evaluate the postoperative effect of clinical bariatric surgery cannot differentiate subcutaneous fats from visceral fats and muscles. Several Quantitative ultrasound (QUS)-based approaches have been developed to quantify hepatic steatosis. QUS techniques (tissue attenuation imaging (TAI), tissue scatter distribution imaging (TSI)) from radio frequency (RF) data analysis as a means for the detection and grading of hepatic steatosis has been posited as an objective and noninvasive approach. The implementation and standardization of QUS techniques (TAI, TSI) in assessing hepatic steatosis quantitatively after bariatric surgery is of high-priority. Our study is aimed to assess hepatic steatosis with QUS techniques (TAI, TSI) in morbidly obese individuals before and after bariatric surgery, and to compare with anthropometric measurements, laboratory assessments and other imaging methods.

Methods and analysis

The present investigation, a self-discipline examination of navigational capacity devoid of visual cues, is designed as a single-site, forward-looking evaluation of efficacy with the imprimatur of the institutional review board. The duration of the study has been provisionally determined to span from 1 January 2023 through 31 December 2025. Our cohort shall encompass one hundred participants, who was scheduled to undergo Roux-en-Y gastric bypass (RYGB) at Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. All patients will undergo anthropometric measurements, blood-based biochemical analyses, ultrasonic examination and magnetic resonance imaging proton density fat fraction (MRI-PDFF). The primary endpoint is the analysis of evaluating the efficacy of QUS techniques assessing hepatic steatosis compared to other methods before and after bariatric surgery.

Results

Prior to the fomal study, we recruited 21 obese Chinese participants who received ultrasonic examination (TAI, TSI) and MRI-PDFF. AC-TAI showed moderate correlations with MRI-PDFF (adjusted r = 0.632; P < 0.05). For MRI-PDFF ≥10%, SC-TSI showed moderate correlations with MRI-PDFF (adjusted r = 0.677; P < 0.05).

Conclusion

Our pre-experiment results signified that using QUS techniques for postoperative evaluation of bariatric surgery is promising. QUS techniques will be signed a widespread availability, real-time functionality, and low-cost approach for assessing hepatic steatosis before and after bariatric surgery in obese individuals, thus is capable for subsequent scale-up liver fat quantification.

Ethics and dissemination

The present research endeavor has been bestowed with the imprimatur of the Ethics Committee of the Hospital, as indicated by its Approval Number: 2023-KY-015. In due course, upon completion of the study, we intend to disseminate our findings by publishing them in a suitable academic journal, thereby facilitating their widespread utilization.

Registration

The trial is duly registered with the Chinese Clinical Trial Registry, and with a unique Trial Registration Number, ChiCTR2300069892, approved on March 28, 2023.

Lower survival and higher rates of cirrhosis in patients with ROUX-EN-Y gastric bypass hospitalised with alcohol-associated hepatitis

OBJECTIVE

The incidence of alcohol-associated liver disease (ALD) is increasing, and weight loss surgery is more common due to the obesity epidemic. Roux-en-Y gastric bypass (RYGB) is associated with alcohol use disorder and ALD; however, its impact on outcomes in patients hospitalised for alcohol-associated hepatitis (AH) is unclear.

DESIGN

We performed a single-centre, retrospective study of patients with AH from June 2011 to December 2019. Primary exposure was the presence of RYGB. The primary outcome was inpatient mortality. Secondary outcomes included overall mortality, readmissions and cirrhosis progression.

RESULTS

2634 patients with AH met the inclusion criteria; 153 patients had RYGB. Median age of the entire cohort was 47.3 years; median Model for End Stage Liver Disease - Sodium (MELD-Na) was 15.1 in the study group versus 10.9 in the control group. There was no difference in inpatient mortality between the two groups. On logistic regression, increased age, elevated body mass index, MELD-Na >20 and haemodialysis were all associated with higher inpatient mortality. RYGB status was associated with increased 30-day readmission (20.3% vs 11.7%, p<0.01), development of cirrhosis (37.5% vs 20.9%, p<0.01) and overall mortality (31.4% vs 24%, p=0.03).

CONCLUSIONS

Patients with RYGB have higher rates of readmissions, cirrhosis and overall mortality after discharge from hospital for AH. Allocation of additional resources on discharge may improve clinical outcomes and reduce healthcare expenditure in this unique patient population.

Safety of liver biopsy at the time of bariatric surgery: an analysis of the MBSAQIP database

BACKGROUND

The majority of patients undergoing bariatric surgery have hepatic steatosis. Liver biopsy is not technically difficult to perform at the time of metabolic and bariatric surgery (MBS), but there may be concerns for bleeding complications. The safety of liver biopsy (LBx) at the time of MBS has been studied in single institutional studies but has not been studied on a national level.

METHODS

The MBSAQIP database for 2015-2018 was examined. The codes for Roux-en-Y gastric bypass (RYGB) of 43644 and sleeve gastrectomy (SG) 43775 were used along with 47000 (percutaneous liver biopsy), 47001 (percutaneous liver biopsy at time of other procedure), and 47379 (unlisted laparoscopic procedure, liver). Outcomes such as operative time, complications, and length of stay were examined. Propensity-matched analysis was performed to evaluate for adjusted associations.

RESULTS

There were 546,532 patients that met our inclusion criteria. Of those, 21,367 (3.9%) underwent LBx. Only 5.5% (8012) of patients undergoing RYGB had a LBx and 3.3% (13,355) of SG patients. Patients who underwent a LBx had a longer operative time before (103 min vs 84 min, p < 0.001) and after propensity matching [regression coefficient (RC): 10.7 (8.87, 12.5)]. There was no increase in length of stay. There was an increased risk in mortality in the unadjusted analysis (prevalence ratio = 1.61, p = 0.02), but when propensity-matched analysis was done, there was no statistically significant difference between the two groups. Concerning bleeding or transfusion, there was no difference in bleeding or rates of transfusion (p= 0.22, p = 0.21).

CONCLUSION

Liver biopsy at the time of MBS is safe. It adds operative time, but there is no increase in length of stay, bleeding complications, morbidity, or death.

The Use of Transient Elastography Technology in the Bariatric Patient: a Review of the Literature

Transient elastography (TE) is a non-invasive technology that demonstrates promise in assessing liver steatosis and fibrosis without the risks of traditional percutaneous liver biopsy. Many studies have examined its reliability in respect to liver biopsy, but fewer have examined using TE in obese and bariatric surgery patients. With evidence showing that bariatric surgery can lead to improvement of liver steatosis and fibrosis, TE has the potential to provide a simple avenue of hepatic assessment in patients before and after procedures. This review article investigates what is known about the reliability of TE and its implementation in obese and bariatric surgery patients.