Effects of Laparoscopic Sleeve Gastrectomy on Non-Alcoholic Steatohepatitis and Liver Fibrosis in Japanese Patients with Severe Obesity

Relationships Between Changes in Serum Ketone Body Levels and Metabolic Effects in Patients with Severe Obesity Who Underwent Laparoscopic Sleeve Gastrectomy

BACKGROUND

Serum ketone bodies increase due to dynamic changes in the lipid metabolisms of patients undergoing bariatric surgery. However, there have been few studies on the role of ketone bodies after bariatric surgery. We aimed to clarify the role of and relationship between the changes in serum ketone bodies and weight loss, as well as between those changes and the metabolic effects after laparoscopic sleeve gastrectomy (LSG).

METHODS

We recruited 52 patients with severe obesity who underwent LSG. We measured acetoacetic acid (AcAc) and β-hydroxybutyric acid (β-OHB) at the baseline, 1 month, and 6 months after LSG. Subsequently, we compared the changes in the serum ketone bodies with weight-loss effects and various metabolic parameters.

RESULTS

At 1 month after LSG, β-OHB significantly increased (p = 0.009), then significantly decreased 6 months after LSG (p = 0.002). In addition, β-OHB in patients without Type 2 diabetes (T2D) and metabolic dysfunction-associated steatohepatitis (MASH) was notably higher than in patients with T2D at 1 month after LSG (p < 0.001). In the early phase, both AcAc and β-OHB mainly had strong positive correlations with changes in T2D- and MASH-related parameters. In the middle term after LSG, changes in both AcAc and β-OHB were positively correlated with changes in lipid parameters and chronic kidney disease-related parameters.

CONCLUSION

We demonstrated that the postoperative surge of ketone bodies plays a crucial function in controlling metabolic effects after LSG. These findings suggest the cause- and consequence-related roles of ketone bodies in the metabolic benefits of bariatric surgery.

The Role Bariatric Surgery and Endobariatric Therapies in Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Disease spectrum varies from steatosis, steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Currently, there are no approved medical therapies, and weight loss through lifestyle modifications remains a mainstay of therapy. Bariatric surgery is the most effective therapy for weight loss and has been shown to improve liver histology. Recently, endoscopic bariatric metabolic therapies have also emerged as effective treatments for patients with obesity and NAFLD. This review summarizes the role of bariatric surgery and endoscopic therapies in the management of patients with NAFLD.

Identification of a Fatty Acid for Diagnosing Non-Alcoholic Steatohepatitis in Patients with Severe Obesity Undergoing Metabolic Surgery

The prevalence of nonalcoholic steatohepatitis (NASH) in severely obese Japanese patients is extremely high. However, there are currently no methods other than liver biopsy to assess hepatic steatosis and fibrosis. The purpose of this study was to comprehensively analyze changes in fatty acid (FA) and serum-free fatty acid (FFA) metabolism in severely obese Japanese patients to determine whether these could be surrogate markers. In this study, we enrolled 20 Japanese patients who underwent laparoscopic sleeve gastrectomy (LSG) for severe obesity and intraoperative liver biopsy. Serum FFAs were analyzed with liquid chromatography-mass spectrometry, and FAs in liver tissue were assessed using matrix-assisted laser desorption/ionization-imaging mass spectrometry to determine FAs that may be indicative of a positive NASH diagnosis. All patients showed significant weight loss and metabolic improvement following LSG. Regarding weight loss and metabolic improvement indices, 23 FFAs showed significant correlations with the baseline data. Narrowing down the phospholipids to commonly detected FAs detected in liver tissue, PC(18:1e_20:4) was significantly changed in the NASH group, suggesting that it could be used as a surrogate marker for NASH diagnosis. The results suggest that specific postoperative changes in blood phospholipids could be used as surrogate markers for NASH treatment.

Bariatric Surgery is Effective and Safe for Obese Patients with Compensated Cirrhosis: A Systematic Review and Meta-Analysis

BACKGROUND

With the global pandemic of obesity and nonalcoholic fatty liver disease (NAFLD), the incidence of cirrhosis associated with nonalcoholic steatohepatitis (NASH) has greatly increased. This study aimed to evaluate the efficacy and safety of bariatric surgery in obese cirrhotic patients.

METHODS

PubMed, EMBASE, and the Cochrane Library were searched for relevant studies. Effectiveness outcomes were weight loss, remission of comorbidities, and improvement in liver function. Safety outcomes were procedural complications and mortality.

RESULTS

A total of 15 studies were included in this meta-analysis. Patients with compensated cirrhosis lost weight significantly after surgery, and the percentage of excess weight loss was 60.44 (95% CI, 44.34 to 76.55). Bariatric surgery resulted in remission of NAFLD in 57.9% (95% CI, 27.5% to 88.3%), T2DM in 58.4% (95% CI, 48.4% to 68.4%), hypertension in 53.1% (95% CI, 43% to 63.3%), dyslipidemia in 59.8% (95% CI, 41.1% to 78.5%) of patients with cirrhosis. Bariatric surgery reduced the levels of alanine aminotransferase and aspartate aminotransferase. The incidence of surgical complications in patients with cirrhosis was about 19.2% (95% CI, 11.7% to 26.6%), which was higher than that in patients without cirrhosis (OR 2.67 [95% CI, 1.26 to 5.67]). Patients with cirrhosis had an overall mortality rate of 1.3%, and the mortality rates for compensated cirrhosis and decompensated cirrhosis were 0.9% and 18.2%, respectively.

CONCLUSIONS

Bariatric surgery is effective for weight loss, remission of comorbidities, and reversal of liver damage. Although cirrhotic patients have a higher risk of complications and death, bariatric surgery is relatively safe for well-compensated cirrhosis.

The Concept of Indeterminable NASH Inducted by Preoperative Diet and Metabolic Surgery: Analyses of Histopathological and Clinical Features

Practitioners routinely perform intraoperative liver biopsies during laparoscopic sleeve gastrectomy (LSG) to evaluate nonalcoholic fatty liver disease (NAFLD). In some patients, hepatocyte ballooning, inflammation, and fibrosis without steatosis are observed, even in the absence of other etiologies. We call this finding indeterminable nonalcoholic steatohepatitis (Ind-NASH). In this study, we clarified the prevalence, as well as histopathological and clinical features, of Ind-NASH through intraoperative liver biopsy in Japanese patients presenting with severe obesity. We enrolled 63 patients who had undergone LSG and intraoperative liver biopsy. In patients diagnosed with histopathological NASH, we performed protocol liver biopsies at 6 and 12 months after LSG. We statistically analyzed these histopathological findings and clinical parameters and found the prevalence rate of Ind-NASH discovered through intraoperative biopsy to be 15.9%. Protocol liver biopsy also revealed that Ind-NASH was an intermediate condition between NASH and normal liver. The clinical features of patients with Ind-NASH are a higher body weight compared to NASH (134.9 kg vs. 114.7 kg; p = 0.0245), stronger insulin resistance compared to nonalcoholic fatty liver (homeostasis model assessment–insulin resistance: 7.1 vs. 4.9; p = 0.0188), and mild liver dysfunction compared to NASH. Patients with Ind-NASH observed positive weight-loss effects from a preoperative diet compared to the postoperative course (percentage total weight loss: 32.0% vs. 26.7%; p < 0.0001). Patients with Ind-NASH may also be good candidates for metabolic surgery owing to their good treatment response; therefore, efforts should be made by specialists in the near future to deeply discuss and define Ind-NASH.

Liver retraction using an L-shaped retractor during sleeve gastrectomy

PURPOSE

The Nathanson liver retractor (NLR) and the snake liver retractor (SLR) are commonly used in bariatric surgery and their use is associated with some disadvantages. We developed an L-shaped liver retractor (LLR) and herein evaluated its efficacy and safety.

METHODS

The present retrospective study enrolled patients undergoing sleeve gastrectomy in our department between June 2014 and December 2020. The patients were divided into three groups according to the liver retractor used (LLR, SLR or NLR) for a comparative analysis of the efficacy and safety of the devices. The procedural time (PT) of each retractor type, defined as the time from retractor insertion to liver fixation, was compared.

RESULTS

In total, 140 patients successfully underwent laparoscopic sleeve gastrectomy. The LLR, SLR and NLR were used in 37, 91, and 12 of these patients, respectively. The PT for the LLR was the shortest. AST/ALT elevation was significantly more frequent in the NLR group than in the SLR group and tended to be less frequent in the LLR group in comparison to the NLR group (p = 0.09). The length of hospital stay in the NLR group was significantly longer in comparison to the LLR group.

CONCLUSION

Our study suggested that the LLR was superior to the conventional liver retractors used in sleeve gastrectomy.

Metabolic surgery in treatment of obese Japanese patients with type 2 diabetes: a joint consensus statement from the Japanese Society for Treatment of Obesity, the Japan Diabetes Society, and the Japan Society for the Study of Obesity

Bariatric surgery has been shown to have a variety of metabolically beneficial effects for patients with type 2 diabetes (T2D), and is now also called metabolic surgery. At the 2nd Diabetes Surgery Summit held in 2015 in London, the indication for bariatric and metabolic surgery was included in the “algorithm for patients with type T2D”. With this background, the Japanese Society for Treatment of Obesity (JSTO), the Japan Diabetes Society (JDS) and the Japan Society for the Study of Obesity (JASSO) have formed a joint committee to develop a consensus statement regarding bariatric and metabolic surgery for the treatment of Japanese patients with T2D. Eventually, the consensus statement was announced at the joint meeting of the 38th Annual Meeting of JSTO and the 41st Annual Meeting of JASSO convened in Toyama on March 21, 2021. In preparing the consensus statement, we used Japanese data as much as possible as scientific evidence to consider the indication criteria, and set two types of recommendation grades, “recommendation” and “consideration”, for items for which recommendations are possible. We hope that this statement will be helpful in providing evidence-based high-quality care through bariatric and metabolic surgery for the treatment of obese Japanese patients with T2D.

High frequency and long persistency of ballooning hepatocyte were associated with glucose intolerance in patients with severe obesity

Nonalcoholic steatohepatitis (NASH) and glucose intolerance are associated with an increased risk of mortality in patients with severe obesity; however, whether histological findings of the liver are related to glucose intolerance in these patients remain unknown. Sixty-nine consecutive patients who underwent metabolic surgery between June 2008 and February 2020 were included; histological findings of the liver and laboratory data were analyzed. Twenty patients with biopsy-proven NASH were chronologically evaluated using sequential biopsies; data before metabolic surgery was considered as the baseline. Glucose intolerance—demonstrated by an increased area under the curve (AUC) for blood sugar (BS) during the 75-g oral glucose tolerance test—and increased homeostatic model assessment for insulin resistance (HOMA-IR) correlated with the grade of hepatocyte ballooning in patients. Patients with persistent ballooning at the follow-up biopsy had a higher HOMA-IR, high AUC for BS, and lower adiponectin level than those in patients in whom ballooning was eliminated, while there was no significant difference in body weight. We concluded that glucose intolerance was associated with the grade of hepatocyte ballooning; additionally, persistent hepatocyte ballooning sustained glucose intolerance, while elimination of hepatocyte ballooning improved the condition. Glucose intolerance may, thus, mediate balloon formation of the hepatocyte.

Therapeutic effects of sleeve gastrectomy for non-alcoholic steatohepatitis estimated by paired liver biopsy in morbidly obese Japanese patients

Bariatric surgery has been reported to improve non-alcoholic steatohepatitis (NASH), which is a frequent comorbidity in morbidly obese patients. We performed a retrospective cohort study to estimate the therapeutic effect of sleeve gastrectomy (SG), the most common bariatric surgery in Japan, on obese patients with NASH by comparing the findings of paired liver biopsies.Eleven patients who underwent laparoscopic SG for the treatment of morbid obesity, defined as body mass index (BMI) > 35 kg/m2, from March 2015 to June 2019 at Hiroshima University Hospital, Japan, were enrolled. All patients were diagnosed with NASH by liver biopsy before or during SG and were re-examined with a second liver biopsy 1 year after SG. The clinical and histological characteristics were retrospectively analyzed.One year after SG, body weight and BMI were significantly reduced, with median reductions in body weight and BMI of-22 kg and -7.9 kg/m2, respectively. Body fat was also significantly reduced at a median of 13.7%. Liver-related enzymes were also significantly improved. On re-examination by paired liver biopsy, liver steatosis improved in 9 of the 11 patients (81.8%), ruling out of the pathological diagnosis of NASH. However, fibrosis stage did not significantly improve 1 year after SG. The non-alcoholic fatty liver disease activity score was significantly reduced in 10 of 11 patients (90.9%).Pathological improvement or remission of NASH could be achieved in most morbidly obese Japanese patients 1 year after SG.

Predictive scoring system for advanced liver fibrosis in Japanese patients with severe obesity

PURPOSE

The aim of this study was to examine the predictive scoring system of advanced liver fibrosis in severely obese Japanese patients.

METHODS

Seventy-two patients underwent laparoscopic sleeve gastrectomy and intraoperative liver biopsies. We classified these patients into two groups: Brunt stage ≥ 2 (advanced fibrosis) and 0/1 (none/mild fibrosis). A logistic regression analysis was performed to identify the predictors of advanced fibrosis.

RESULTS

Sixteen patients had advanced fibrosis, while 56 had no/mild fibrosis. The prevalence of type 2 diabetes mellitus (T2DM) in advanced fibrosis group was significantly higher than in none/mild fibrosis. An univariate analysis of the factors predicting advanced fibrosis showed significant differences in AST/ALT ratio, serum insulin levels, HOMA-IR, and type IV collagen 7S in the T2DM group. According to a multivariate analysis, type IV collagen 7S was an independent predictor and the cutoff value was 5.6 ng/mL. We created a flow chart; high risk (T2DM and type IV collagen 7S ≥ 5.6 ng/mL), moderate risk (T2DM and type IV collagen 7S < 5.6 ng/mL), and low risk (non-DM). For those at high risk, the sensitivity, specificity, positive predictive value, and negative predictive value were 56.2%, 94.4%, 75.0%, and 87.9%, respectively.

CONCLUSION

This classification system has the potential to accurately categorize the risk of liver fibrosis.

First Case Report of Fulminant Hepatitis After Laparoscopic Sleeve Gastrectomy Associated with Concomitant Maximal Therapeutic Dose of Acetaminophen Use, Protein Calorie Malnutrition, and Vitamins A and D, Selenium, and Glutathione Deficiencies

Nonalcoholic fatty liver disease (NAFLD) is increasingly being linked to obesity. Although laparoscopic sleeve gastrectomy (LSG) is effective for weight loss that can ultimately resolve NAFLD, an initial transient deterioration of liver functions could be observed during the first few months post-operatively, after which a subsequent improvement of the liver functions might occur. Rapid weight loss, nutritional deficiencies, and protein malnutrition can all contribute to hepatic dysfunction and can affect the metabolism of medications such as acetaminophen leading to more insult to a compromised liver. We report acute liver failure after LSG associated with protein calorie malnutrition, multiple nutritional deficiencies in addition to concomitant use of therapeutic doses of acetaminophen. Treatment with N-acetylcysteine, and replacement of deficient multivitamins and trace elements resulted in significant improvement in liver functions.