S747 Effect of Diet on Weight Loss Outcomes in Patients After Bariatric Therapies

Introduction: Sleeve gastrectomy (SG) has emerged to be the most common bariatric intervention for weight loss in last decade. In some reports, vegetarianism has been reported to be associated with lower risk of diabetes, heart disease and all-cause mortality. Whether this dietary influence influences any weight loss outcomes in population remains to be seen. This study aims to compare weight loss profiles between vegetarian diet versus regular non-vegetarian diet patients who underwent SG over a year and evaluate whether there is any difference in outcomes due to dietary patterns. Methods: This is a retrospective study of patients who underwent SG at our institute from 2018-2024. Patients were followed for a period of one year from laparoscopic SG (LSG) for weight loss outcomes. Demographics, dietary patterns, AEs, and weight profiles were collected. The primary outcome was total weight loss (TWL) and %TWL comparisons between patients who took vegetarian diet versus regular non-vegetarian diet. Secondary outcomes included comparison of adverse events (AEs). A Fisher exact test was used to compare the AE rate, and a student t-test was used for weight comparisons. Results: One hundred forty-two vegetarian (group 1) and 1,557 non-vegetarian diet (group 2) patients were included who underwent LSG. Baseline characteristics were similar between groups. Mean preoperative weight (pounds) was 266 ± 91 and 271.68 ± 58.8 in Groups 1 and 2, while body mass index (Kg/m2) was 43.6 ± 8.5 and 44.3 ± 8.18. Total weight loss (TWL) (pounds) between Group 1 and 2 at 6 and 12 months were (52.06 ± 22.2 and 52.24 ± 24.18, P = 0.93) and (60.52 ± 27 and 62.6 ± 30.6, P = 0.46) respectively. %TWL in groups 1 and 2 were (19.26 ± 6.73 and 19.18 ± 7.63, P = 0.90) and (22.65 ± 9.64 and 23.19 ± 9.81, P = 0.56) at 6 and 12 months. The AE rate in the vegetarian group (0%) was lower than the non-vegetarian group (0.32%) but not statistically significant. There was no significant difference in weight loss at 6 months and 1 year. Weight comparisons between preoperative weight and 6- or 12-months weight was statistically significant in either group (P < 0.0001). Conclusion: Dietary behavior does not influence change in outcomes after bariatric therapy with SG. Lower adverse events were seen in vegetarian patients without any significant difference. Further studies of dietary behavior in larger populations with surgical as well as endoscopic bariatric therapies can shed more light into the influence of dietary behavior and weight loss outcomes.