Safety and efficacy of sleeve gastrectomy in non-diabetic individuals with class I vs. class II obesity: a matched controlled experiment from Tehran Obesity Treatment Study (TOTS)

Background: This study aimed to evaluate the 3-year outcomes of sleeve gastrectomy in non-diabetic individuals with class I obesity. Methods: A total of 78 participants with class I obesity and 78 participants with class II obesity, matched in terms of age, sex (93.6% female), and the rates of dyslipidemia and hypertension, were included in this prospective cohort study.Follow-up data, including metabolic features, body composition, nutritional characteristics, and surgery complications, were gathered at the baseline and 6, 12, 24, and 36 months post-bariatric surgery. Micronutrient deficiencies and comorbidities (hypertension and dyslipidemia) were evaluated in both groups using conditional logistic regression analysis, and Clavien–Dindo classification was used to compare surgical complications. Results: Baseline characteristics of the participants in both groups were similar (n= 78, mean age: 36.4 ± 8.5). The two groups were also comparable in terms of weight loss, cardiovascular risk factors, and remission of obesity-related comorbidities 3 years following sleeve gastrectomy. Overall values of Δ total weight loss (TWL)%, Δ excess weight loss (EWL)%, and β (95% CI) were − 1.86 (1.19), and − 2.56 (4.5) with a Pvalue of 0.118 and 0.568, respectively. The occurrence of surgical complications and undesirable outcomes were also similar between the two study groups. Conclusion: Bariatric surgery is an effective and safe method to achieve weight loss and alleviate cardiovascular risk factors and obesity-related comorbidities in non-diabetic individuals with class I and class II obesity.