Vertical Sleeve Gastrectomy Has Better Weight Evolution and Serum Concentrations of Vitamin D when Compared with Roux-Y Gastric Bypass.

Objective: The objective of this study is to compare the weight evolution and serum concentrations of vitamin D in individuals undergoing Roux-en-Y Gastric Bypass (RYGB) and Sleeve after 1 follow-up year.
Methodology: Descriptive, prospective, and longitudinal study, with 108 individuals divided into 2 groups: RYGB (55 patients) and Sleeve (53), evaluated preoperatively, and at 6 and 12 postoperatively months. Anthropometric data, serum concentrations of 25(OH)D, calcium, and parathyroid hormone were analyzed.
Results: The Sleeve group showed greater reductions in excess weight and excess body mass index (BMI) when compared with the RYGB group at both times (p < 0.001). Besides, after 12 months, those who had undergone the Sleeve procedure also had higher percentages of surgical success (84.4% versus 65.0%, p = 0.038). The prevalence of preoperative inadequacy of 25(HO)D in both groups was 78.7%. After 6 months, there was an increase in serum concentrations of 25(HO)D in both groups (p < 0.001), but without significant differences between the groups (p = 0.154). In the comparison between 6 and 12 months, there was only a reduction for the RYGB group (p = 0.001). Also, when comparing both groups, the means of vitamin D in patients undergoing RYGB were also lower after 12 months (p = 0.003). There was a negative correlation between vitamin D and parathyroid hormone (r = - 0.235 p = 0.030). The mean serum concentrations of calcium were adequate at all times.
Conclusion: Patients undergoing the Sleeve procedure had a better evolution in weight loss and are at a lower risk of vitamin D inadequacy than those undergoing RYGB.