Long-term effects of laparoscopic sleeve gastrectomy and Roux-Y-gastric bypass on body composition and bone mass density

Abstract

Abstract Objective Currently, the two most common bariatric procedures are laparoscopic sleeve gastrectomy (LSG) and laparoscopic gastric bypass (LRYGB). Long-term data comparing the two interventions in terms of their effect on body composition and bone mass density (BMD) is scarce. The aim of this study was to assess body composition and BMD at least five years after sleeve gastrectomy (LSG) and gastric bypass (LRYGB). Methods Bariatric patients at least five years post-surgery (LSG or LRYGB) were recruited and body composition and BMD was measured by means of DEXA. Data from body composition before surgery was included in the analysis. Blood samples were taken for determination of plasma calcium, parathyroid hormone (PTH), Vitamin D3, alkaline phosphatase and C-terminal telopeptide (CTX), and individual risk for osteoporotic fracture assessed by The Fracture Risk Assessment Tool (FRAX) score was calculated. After surgery, all patients received multivitamins, vitamin D3, and zinc. In addition, LRYGB-patients were prescribed calcium. Results A total of 142 patients were included, 72 LSG and 70 LRYGB, before surgery: median BMI 43.1 kg/m2, median age 45.5 years, 62.7% females. Follow-up after a median of 6.7 years. For LRYGB, percentage total weight loss (%TWL) at follow up was 26.3%, and for LSG 24.1%, (p = 0.243). LRYGB lead to a slightly lower fat percentage in body composition. At follow-up, 45% of both groups had a T-score at the femoral neck below -1, indicating osteopenia. No clinically relevant difference between the groups in BMD was found. Conclusion At 6.7 years post-surgery, no difference in body composition and BMD between LRYGB and LSG was found. Deficiencies and bone loss remain an issue after both interventions and should be monitored.