Current status of laparoscopic bariatric/metabolic surgery in Japan: The sixth nationwide survey by the Japan Consortium of Obesity and Metabolic Surgery

The impact on obesity-related quality of life and eating satisfaction in the early period after laparoscopic sleeve gastrectomy

INTRODUCTION

Obesity impairs patients' quality of life (QoL). Laparoscopic sleeve gastrectomy (LSG) is a common procedure for patients with severe obesity; however, studies reporting changes in obesity-related QoL are limited. The aim of this study was to assess changes in obesity-related QoL and food tolerance in the early postoperative period.

METHODS

We included 20 consecutive patients who underwent LSG between May 2021 and July 2023. We evaluated changes in obesity-related QoL 6 months after surgery using an obesity and weight loss QoL questionnaire (OWLQOL) and a weight related symptom measure (WRSM). Additionally, we assessed eating satisfaction and food tolerance after surgery.

RESULTS

The percentages of total weight loss and excess weight loss were 28.5% and 79.1%, respectively. OWLQOL scores and WRSM changed from 36.5 to 73.0 points and from 44.0 to 15.0 points (p = .007, .007), respectively. The food tolerance score decreased from 25 to 21.2 points (p < .001), while eating satisfaction showed no significant change (p = .25).

CONCLUSION

Obesity-related QoL is enhanced even in the early postoperative period, without sacrificing eating satisfaction. The findings of this study may provide valuable insights for patients when considering LSG.

Laparoscopic sleeve gastrectomy combined with Toupet fundoplication (T-sleeve): A short report of a Japanese obesity patient with gastroesophageal reflux disease

Laparoscopic sleeve gastrectomy (LSG) is the most frequently performed procedure in bariatric-metabolic surgery (BMS) worldwide, accounting for approximately 90% of BMS procedures in Japan. While numerous studies have reported on the safety and efficacy of LSG, gastroesophageal reflux disease (GERD) remains a major postoperative complication. Although Roux-en-Y gastric bypass (RYGB) is preferred for severe obesity with GERD, it is less suitable for Japanese patients who have a higher risk of gastric cancer due to the remnant stomach which is difficult to observe with esophago-gastro-duodenoscopy. To address de novo and exacerbation GERD after LSG, we conducted LSG with Toupet fundoplication (T-sleeve) for Japanese patients with severe obesity. In our first T-sleeve case, the patient demonstrated sufficient weight loss and improved GERD following surgery. Hence, we suggest that T-sleeve is a feasible option for Japanese patients with obesity and concurrent GERD.

Laparoscopic sleeve gastrectomy followed by laparoscopic adrenalectomy for patients with obesity and primary aldosteronism: Report of two patients

INTRODUCTION AND IMPORTANCE

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension. Surgical treatment of unilateral PA usually resolves excessive aldosterone secretion. Obesity is an independent factor for postoperative persistent hypertension for patients with unilateral PA. Laparoscopic sleeve gastrectomy has become popular due to its efficacy in resolving obesity. A specific strategy might to be needed for patients with unilateral PA and obesity.

CASE PRESENTATION

Two males with PA and obesity (Body Mass Index: BMIs of 35.9 and 39.0, respectively) were referred for evaluation. Both patients had hypertension caused by PA and obesity. We performed laparoscopic sleeve gastrectomy (LSG) prior to adrenalectomy to avoid persistent postoperative hypertension and perioperative obesity related comorbidities. LSG could lead to decreasing of BMIs to 27.7 and 32.1. Comorbidities associated with obesity were also resolved in both patients. Laparoscopic adrenalectomy was then safely performed in these two patients with PA.

CLINICAL DISCUSSIONS

Patients with PA developing resistant hypertension were estimated to be 20 % of those who underwent adrenalectomy. Decreased BMI can be an independent preoperative determinant for successful outcome after adrenalectomy regarding hypertension. We need to review with special care the preoperative BMI and the nature of hypertension before performing surgery on patients with unilateral PA.

CONCLUSIONS

A successful strategy was used to treat two obese patients with unilateral PA who underwent laparoscopic adrenalectomy after LSG to minimize complications associated with obesity-related comorbidities.

Treatments for Staple Line Leakage after Laparoscopic Sleeve Gastrectomy

The number of laparoscopic sleeve gastrectomies (LSGs) performed in patients with obesity who are eligible for bariatric and metabolic surgery is currently much lower in Japan than in other countries. Considering the large number of potential patients with obesity and type 2 diabetes and the unique Japanese national health insurance system that guarantees fair healthcare delivery, there is room to increase the number of LSGs in Japan in the near future. However, strict health insurance regulations may limit access to mandatory devices needed to treat postoperative complications, such as staple line leakage, which can cause severe morbidity and even mortality. Therefore, understanding the pathogenesis and treatment options for this complication is crucial. This article examined the current situation in Japan and its impact on staple line leakage management, including the role of endoscopic treatment in reducing reoperation. The authors suggest increasing education and collaboration between healthcare professionals to optimize management and improve patient outcomes.

Preoperative Serum Cortisol Level Is Predictive of Weight Loss After Laparoscopic Sleeve Gastrectomy in Men with Severe Obesity but Not Women

BACKGROUND

Bariatric surgery is an effective treatment for severe obesity and its associated medical problems. Preoperative factors that predict postoperative weight loss remain to be fully characterized, however.

METHODS

Anthropometric and laboratory data were collected retrospectively for severely obese patients who underwent laparoscopic sleeve gastrectomy (LSG) between April 2016 and July 2019 at our hospital. Preoperative factors that predicted weight loss at 1 year after LSG were investigated.

RESULTS

A total of 122 subjects (45 men and 77 women) underwent LSG. The mean ± SD age and body mass index at surgery were 44.4 ± 10.4 years and 40.7 ± 6.7 kg/m². The percent total weight loss (%TWL) was 27.0 ± 8.6 among all subjects, 26.4 ± 8.0 among men, and 27.4 ± 8.9 among women, with no significant difference between the sexes. The %TWL showed a significant inverse correlation with serum cortisol level in men and with age and the visceral/subcutaneous fat area ratio in women. Multivariable regression analysis revealed the presence of type 2 diabetes and the serum cortisol concentration to be negatively associated with %TWL among all subjects and men, respectively. Receiver operating characteristic curve analysis identified an optimal cutoff of 10 µg/dL for prediction of a %TWL of ≥ 25 in men by serum cortisol level.

CONCLUSIONS

Serum cortisol concentration was identified as a predictor for postoperative weight loss in men. Our results may thus help inform the decision to perform LSG or more effective surgical procedures in men with severe obesity.

Factors Associated with Relapse of Type 2 Diabetes Mellitus after Laparoscopic Sleeve Gastrectomy in Japanese Subjects: A Subgroup Analysis of J-SMART Study

INTRODUCTION

Laparoscopic sleeve gastrectomy (LSG) for morbidly obese patients often results in remission of type 2 diabetes (T2DM), but diabetes relapses in some of those patients. The frequency of T2DM relapse in Asians and the factors involved have not been adequately investigated.

METHODS

The J-SMART study was conducted on 322 Japanese subjects with body mass index (BMI) ≥32 kg/m2 who underwent LSG at 10 accredited centers in Japan between 2011 and 2014. Of these, 82 T2DM subjects with diabetes in complete or partial remission at 1 year after LSG and followed postoperatively for 5 years were included in the subgroup analysis and classified into two groups: diabetes remission-maintained and diabetes relapse.

RESULTS

The mean age of all included subjects was 49.2 years, median BMI was 41.5 kg/m2, and median HbA1c was 6.7%. Compared with the diabetes remission-maintained group, the diabetes relapse group at 5 years after LSG had significantly higher preoperative HbA1c, number of antidiabetic medications, and high-density lipoprotein cholesterol level; and lower BMI and homeostasis model assessment-beta cell function (HOMA-β). As many as 83.0% of the subjects were able to achieve HbA1c <7% at 5 years after LSG, but 26.8% of the subjects had diabetes relapse. Preoperative HbA1c significantly contributed to diabetes relapse (odds ratio 1.54, p = 0.049). In addition, the diabetes relapse group tended to have lower percentage total weight loss (%TWL) at 1 year after LSG and higher percentage weight regain (%WR) from postoperative nadir weight, compared with the diabetes remission-maintained group. The hazard ratio for diabetes relapse was 3.14-fold higher in subjects with %TWL ≥20% and %WR ≥25%, and 5.46-fold higher in those with %TWL <20% and %WR ≥25%, compared with %TWL ≥20% and %WR <25%.

CONCLUSION

While LSG provides a high remission rate for T2DM, relapse is not uncommon. Preoperative HbA1c, poor weight loss, and excess weight regain after LSG contribute to diabetes relapse, suggesting the importance of treatment strategies focusing on these factors.

Ten Years of Change in Bariatric/Metabolic Surgery in the Asia-Pacific Region with COVID-19 Pandemic: IFSO-APC National Reports 2021

Background

On November 25, 2021, the IFSO-Asia–Pacific Chapter (IFSO-APC) Virtual Meeting 2021 was held online, and the representatives from the Asia–Pacific region presented 10 years of change in bariatric/metabolic surgery and the influence of COVID-19 in the special session of “IFSO-APC National Reports 2010–2020”. We herein report the summarized data.

Methods

National bariatric/metabolic surgery data, which included the data of 2010 and 2020, were collected from the representatives using a questionnaire that consisted of 10 general questions. At the congress, the data were calculated and summarized.

Results

Thirteen of the 14 national societies responded to the survey. From 2010 to recent years, the populations of individuals with obesity (BMI ≥ 30 kg/m²) and individuals with diabetes both significantly increased. Eight countries and regions expanded the lower limit of criteria for bariatric surgery by 2–5 kg/m² (BMI), and 5 countries newly established criteria for metabolic surgery in the last ten years. Sixty-nine percent of the countries currently run public health insurance systems, which doubled from 2010. The number of bariatric surgeons and institutions increased more than threefold from 2010. In 2010, 2019, and 2020, surgeons in IFSO-APC societies performed 18,280, 66,010, and 49,553 bariatric/metabolic surgeries, respectively. Due to the COVID pandemic, restriction policies significantly reduced access to surgery in South and Southeast Asian countries. The biggest changes included increased numbers of bariatric surgeons and institutions, operation numbers, public insurance coverage, raising awareness, and national registry systems.

Conclusion

For the last 10 years, bariatric/metabolic surgery has rapidly grown in the Asia–Pacific region.

Changes of Short-Chain Fatty Acids and Their Receptors in an Obese Rat Model After Sleeve Gastrectomy

BACKGROUND

Short-chain fatty acids (SCFAs) and gut microbiota have health-related effects and are associated with a wide range of disorders. However, the changes of SCFAs and their receptors after sleeve gastrectomy (SG) remain unclear. This study aimed to examine changes of SCFAs and their receptors after SG in an obese rat model.

METHODS

Thirty obese Sprague-Dawley rats eating a high-energy diet for 6 weeks were divided into three groups: sham-operated (SO) control, pair-fed (PF) control, and SG group. Six weeks after the surgery, metabolic parameters, SCFA levels in the blood and stool, mRNA and protein expression of SCFA receptors in the ileum and epididymal fat, and gut microbiota were examined.

RESULTS

Metabolic parameters in the SG group were significantly improved compared with the SO group. Acetic acid levels in the blood and stool were significantly higher in the SG group than the PF group. The butyric acid level in the stool was also significantly higher in the SG group than in the PF group. In the ileum and epididymal fat, mRNA and protein expression of GPR41 was significantly higher in the SG group than in the other two groups, and mRNA and protein expression of GPR43 was significantly higher in the SG group than in the PF group. Increases in the genera Enterococcus, Lactobacillus, Lactococcus, and Clostridium were observed in the stool after SG.

CONCLUSIONS

SG may activate SCFA pathways through a change in gut microbiota.

Improvements of lung volumes and respiratory symptoms after weight loss through laparoscopic sleeve gastrectomy

PURPOSE

This study evaluated the improvement of respiratory function and airway volumes using spirometry and computed tomography (CT) in severely obese Japanese patients undergoing laparoscopic sleeve gastrectomy (LSG). We also evaluated the quality of life (QOL) of enrolled patients using questionnaires.

METHODS

A total of 71 patients who underwent LSG at Iwate Medical University Hospital between October 2013 and September 2020 were enrolled. The changes and relationships between respiratory parameters including CT volumetry and weight-loss effects were evaluated. Improvements to QOL and bronchial asthma (BA) were also assessed before LSG and 1 year after LSG.

RESULTS

The mean excess weight loss percentage (%EWL) and total weight loss percentage (%TWL) were measured at 55.1% and 26.1%, respectively. The attack frequency of BA significantly decreased (6.1/month vs. 1.5/month; P < 0.001), and the disease severity decreased according to severity classification (P = 0.032). Almost spirometric parameters, lung volume (LV) (4905.0 mL vs. 5490.3 mL; P < 0.001), and airway volume (AV) (108.6 mL vs. 119.3 mL; P = 0.022) significantly improved. The change of functional residual capacity (FRC) was correlated with both %EWL (ρ = 0.69, P < 0.001) and %TWL (ρ = 0.62, P < 0.001). The increase of LV (ρ = 0.79, P < 0.001) and AV (ρ = 0.69, P < 0.001) were correlated with the increase of FRC. Scores of QOL questionnaires dramatically became better owing to improvements in dyspnea.

CONCLUSION

Weight loss effects and the reduction of body fat mass correlated significantly with increase in LV and AV. Improvements of respiratory functions after LSG contributes to QOL and BA symptoms.

Long-term Impact of Laparoscopic Sleeve Gastrectomy on Drug Costs of Japanese Patients with Obesity and Type 2 Diabetes Mellitus

PURPOSE

Laparoscopic sleeve gastrectomy (LSG) is the most common type of bariatric surgery in Japan, and it is the only such procedure covered by national health insurance. The long-term cost of bariatric surgery in Japan has not yet been analyzed. We aimed to evaluate the long-term impact of LSG on the drug treatment costs of patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We retrospectively analyzed data from 230 patients who had undergone LSG at our institution for their obesity and T2DM between 2007 and 2018. The clinicopathological data included age, sex, body mass index (BMI), as well as preoperative and postoperative medications for T2DM, hypertension, and dyslipidemia. We then calculated the drug treatment costs for T2DM, hypertension, and dyslipidemia before and after LSG; and we evaluated the remission rates of these obesity-related diseases.

RESULTS

The median preoperative body weight and BMI of the 230 patients who underwent LSG were 115 kg and 40.6 kg/m², respectively. Preoperative drug treatment costs per month per patient for T2DM, hypertension, and dyslipidemia were ¥3795 (¥0-40285), ¥3269 (¥0-14577), and ¥1428 (¥0-19464). Post-operation, the median drug treatment costs for all these diseases became nil. The remission rates of T2DM, hypertension, and dyslipidemia 5 years after LSG were 82.8%, 50%, and 43.8%, respectively. In Japan, the cost of an LSG operation corresponds to 4.75 years of median drug costs to treat T2DM and hypertension.

CONCLUSION

In the long term, LSG in Japan is effective both physically and cost-wise for patients with obesity and T2DM.

Initial entry via the left upper quadrant with an optical trocar in laparoscopic bariatric surgery

INTRODUCTION

Laparoscopic bariatric surgery (BS) is not readily performed in Japan. To facilitate safe initial access to the abdominal cavity, we insert an optical viewing trocar at a unique site in the left upper quadrant (LUQ). Herein, we describe the technique, its advantages, and outcomes.

MATERIALS AND SURGICAL TECHNIQUE

Briefly, the optical trocar is inserted just below the left subcostal margin, 8 cm from the midline. On insertion, layers of the abdominal wall are visualized on the monitor. Depending on the angle of insertion, five, seven, or eight layers are seen.

DISCUSSION

In assessing our initial entry technique, used in 21 obese patients undergoing laparoscopic sleeve gastrectomy, we found median insertion time to be 25 seconds. There were no related complications. In nearly all (20/21) patients, the abdominal wall was visualized as seven layers: subcutaneous fat, anterior rectus sheath, rectus abdominis muscle, posterior rectus sheath, transverse abdominis muscle, transversalis fascia, and peritoneum. Understanding the layers of the abdominal wall visualized during optical trocar insertion in the LUQ will provide for safe and rapid initial entry in patients undergoing laparoscopic BS and can further the widespread acceptance of laparoscopic BS.

Laparoscopic sleeve gastrectomy for morbid obesity improves gut microbiota balance, increases colonic mucosal-associated invariant T cells and decreases circulating regulatory T cells

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) for morbid obesity may improve gut microbiota balance and decrease chronic inflammation. This study examines the changes in gut microbiota and immune environment, including mucosal-associated invariant T cells (MAIT cells) and regulatory T cells (Treg cells) caused by LSG.

METHODS

Ten morbidly obese patients underwent LSG at our institution between December 2018 and March 2020. Flow cytometry for Th1/Th2/Th17 cells, Treg cells and MAIT cells in peripheral blood and colonic mucosa and 16S rRNA analysis of gut microbiota were performed preoperatively and then 12 months postoperatively.

RESULTS

Twelve months after LSG, the median percent total weight loss was 30.3% and the median percent excess weight loss was 66.9%. According to laboratory data, adiponectin increased, leptin decreased, and chronic inflammation improved after LSG. In the gut microbiota, Bacteroidetes and Fusobacteria increased after LSG, and indices of alpha diversity increased after LSG. In colonic mucosa, the frequency of MAIT cells increased after LSG. In peripheral blood, the frequency of Th1 cells and effector Treg cells decreased after LSG.

CONCLUSIONS

After LSG for morbid obesity, improvement in chronic inflammation in obesity is suggested by change in the constituent bacterial species, increase in the diversity of gut microbiota, increase in MAIT cells in the colonic mucosa, and decrease in effector Treg cells in the peripheral blood.

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.

Gastric Wall Thickness and Linear Staple Height in Sleeve Gastrectomy in Japanese Patients with Obesity

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is a standard procedure due to its low complication rates and favorable outcomes. However, limited data are available regarding the optimal size of linear staplers in relation to gastric wall thickness (GWT).

METHODS

Between August 2016 and December 2020, we performed LSG in 70 patients with an average age, body weight, and body mass index of 42 years, 107 kg, and 40 kg/m², respectively. We measured the GWT at the antrum, body, and fundus using resected specimens. We used an endo-linear stapler, and the closed staple height (CSH) was 1.75 mm.

RESULTS

We found that the average GWT at the antrum was significantly thicker than the GWT at the body and fundus. There was a statistically significant relationship between body weight and the GWT at the antrum and body and obstructive sleep apnea and the GWT at the body. The average CSH/GWT ratios were 0.55, 0.62, and 0.90 at the antrum, body, and fundus, respectively. However, in 20 patients (29%), the CSH/GWT ratio at the fundus area was ≥ 1.0, and only preoperative body weight was a significant predictor for a CSH/GWT ratio of ≥ 1.0.

CONCLUSION

A light body weight may be related to a CSH/GWT ratio of ≥ 1.0 at the fundus.

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.

Predictors of early withdrawal from follow-up visits after laparoscopic sleeve gastrectomy in a Japanese institution

PURPOSE

Postoperative weight loss is related to postoperative adherence to follow-up after bariatric/metabolic surgery, but many patients stop attending follow-up visits early. The aim of this study was to clarify predictors of early withdrawal from follow-up after laparoscopic sleeve gastrectomy (LSG) in a Japanese institution.

METHODS

One hundred and fifty-three patients who underwent LSG were retrospectively included in this study. Multivariate analysis was performed to evaluate independent predictors of withdrawal from follow-up visits within 12 months after LSG among significant or nearly significant factors in the univariate analyses. The discrimination power of significant factors was estimated using area under the receiver operating characteristic curve (AUC).

RESULTS

Within 12 months after LSG, 25 of the 153 patients withdrew from follow-up visits. The multivariate analysis showed that age was the only significant predictor of withdrawal. The AUC for age was 0.685, and the cut-off value was < 40 years. The younger patients (< 40 years old) had a significantly higher rate of withdrawal compared with the older patients (≥ 40 years) (27.0% vs. 8.9%).

CONCLUSION

Older Japanese patients (≥ 40 years old) may be better candidates for LSG. We consider it significant to continue to emphasize the importance of follow-up visits in younger patients after LSG.

Current status of laparoscopic bariatric/metabolic surgery in Japan: The sixth nationwide survey by the Japan Consortium of Obesity and Metabolic Surgery

INTRODUCTION

Laparoscopic bariatric procedures have been performed in Japan since 2000. Laparoscopic sleeve gastrectomy (LSG) has been fully covered by National Health Insurance since 2014, and it has been increasingly performed recently. The Japan Consortium of Obesity and Metabolic Surgery conducts a nationwide survey on laparoscopic bariatric/metabolic surgery every 2 years.

METHODS

The survey was sent by post or email to 97 Japanese institutions in January 2020.

RESULTS

From 2000 to 2019, a total of 3669 laparoscopic bariatric/metabolic procedures were performed in 64 institutions. The most popular procedure was LSG (n = 2866), followed by LSG with duodenojejunal bypass (LSG-DJB, n = 337) and laparoscopic Roux-en-Y gastric bypass (LRYGB, n = 280). Morbidity and reoperation rates were, respectively, 29.8% and 11.8% for LRYGB, 16.8% and 2.8% for LSG, and 13.6% and 6.6% for LSG-DJB. At 5 years after the procedures, the percentage of excess weight loss was 78% for LRYGB, 66% for LSG, and 80% for LSG-DJB.

CONCLUSION

This nationwide survey clearly showed that laparoscopic bariatric/metabolic surgery has been safely and effectively performed for 20 years in Japan.

Background characteristics and diabetes remission after laparoscopic sleeve gastrectomy in Japanese patients with type 2 diabetes stratified by BMI: subgroup analysis of J-SMART

Aim

The J-SMART study was the first national survey of Japanese patients undergoing laparoscopic sleeve gastrectomy (LSG). We performed a subgroup analysis of J-SMART focusing on the differences in patient background and diabetes remission between patients with BMI 32-34.9 kg/m² and those with higher BMI.

Methods

In this multi-institutional retrospective study at 10 certified bariatric institutions, 203 Japanese with type 2 diabetes (T2D) and BMI of 32 kg/m² or higher were analyzed (mean age: 49.2 years, BMI: 43.8 kg/m², HbA1c: 7.6%). Patients were stratified into five groups according to preoperative BMI.

Results

Background characteristics in BMI 32.0-34.9 group were higher adjusted HbA1c, higher visceral/subcutaneous fat area ratio, higher prevalence of diabetic retinopathy, higher frequency of insulin use and lower serum C-peptide. Although 2-year percent total weight loss (21.7%) and diabetes complete remission (CR) rate (52.4%) were lower in BMI 32.0-34.9 group, diabetes improvement rate was 81.0%, and the decrease in HbA1c and number of antidiabetic drugs were comparable or greater than those with higher BMI. Higher BMI and no insulin use were significant independent predictors of diabetes CR. No significant independent predictor was identified for diabetes improvement.

Conclusion

The patients with 32-34.9 kg/m² were characterized by more severe visceral obesity, T2D and the complications, and lower intrinsic insulin secretion capacity. LSG should be considered as a treatment option for patients with BMI 32-34.9 kg/m², to improve diabetes control.

Current Status and Issues Associated with Bariatric and Metabolic Surgeries in Japan

Among Asian countries, laparotomic and laparoscopic bariatric surgeries were introduced in Japan after its establishment in Taiwan. However, despite high prevalence of potential patients with obesity and diabetes, the wider incorporation of surgery into treatment regimen has been stalling for decades in Japan. While the unique Japanese national health insurance system has guaranteed fair healthcare delivery, it might have worked as a barrier to the development of bariatric and metabolic surgeries (BMS). The present article reviews the status of BMS in Japan and discusses recent issues related to its use. To focus on and identify the major obstacles inhibiting the widespread use of BMS, we have comprehensively covered some major areas including the insurance system, surgical indication, accreditation and training system, original research, and national registry.