Abstract
BACKGROUND: Obesity is a major global health concern associated with increased morbidity and mortality. Sleeve gastrectomy is an effective bariatric surgery; however, the impact of resected gastric volume (RGV) on postoperative weight loss remains controversial. AIM: To evaluate the effect of RGV on weight loss and body mass index (BMI) changes in patients undergoing sleeve gastrectomy. METHODS: This retrospective study included 49 patients. Preoperative and postoperative body weight and BMI (at 6 months and 12 months after surgery) were recorded. RGV was calculated using the ellipsoid formula based on the specimen's length, width, and thickness measurements. Statistical analyses included parametric tests, repeated-measures one-way analysis of variance, Bonferroni post-hoc tests, and Pearson correlation analysis. RESULTS: Both body weight and BMI significantly decreased over time (weight: F = 951.34, P < 0.01, η(2) = 0.95; BMI: F = 345.97, P < 0.01, η(2) = 0.88). A positive and statistically significant correlation was found between preoperative body weight and RGV (r = 0.285, P < 0.05). However, no significant associations were identified between RGV and weight or BMI at 6 months and 12 months. CONCLUSION: RGV correlated with preoperative weight but not with postoperative outcomes, indicating that weight loss after sleeve gastrectomy is a multifactorial process and influenced by hormonal, metabolic, and lifestyle factors.