Background characteristics and postoperative outcomes of insufficient weight loss after laparoscopic sleeve gastrectomy in Japanese patients

AIM: Laparoscopic sleeve gastrectomy (LSG) is becoming popular in Japan, but insufficient weight loss is often observed in patients after LSG. We investigated the effect of LSG on obesity‐related comorbidities and identified the background characteristics of Japanese patients with insufficient weight loss after LSG. METHODS: In this multi‐institutional retrospective study at 10 certified bariatric institutions, 322 Japanese patients who underwent LSG with a follow‐up period of more than 2 years were analyzed. Anthropometry, obesity‐related comorbidities and psychosocial background data were collected. Weight loss was expressed as 2‐year percent total weight loss (%TWL). RESULTS: Mean age, body weight, body mass index (BMI) and glycated hemoglobin were 46.9 years, 119.2 kg, 43.7 kg/m(2) and 7.1%, respectively. Prevalence of mental disorders was 26.3%. Mean BMI declined to 30.3 kg/m(2) at 2 years and %TWL was 29.9%. Improvements in the markers and prevalence of obesity‐related comorbidities were observed. Remission rates of diabetes, dyslipidemia and hypertension were 75.6%, 59.7% and 41.8%, respectively. %TWL at the respective cut‐off level of diabetes remission was 20.8%. Lower remission rates of diabetes in patients with %TWL <20%, and less calorie restriction and higher prevalence of mental disorders (46.9%) in patients with %TWL <15% were observed. Frequencies of %TWL <15% and <20% were 6.5% and 18.5%, respectively. CONCLUSION: %TWL 20% was a candidate cut‐off point of insufficient weight loss for diabetes remission after LSG, and mental disorders might be relevant to intractable obesity in Japanese patients.