Changes in bone mineral density and bone metabolism after sleeve gastrectomy: a systematic review and meta-analysis

Background: Roux-en-Y gastric bypass surgery adversely affects bone health. The evidence is less well-described for sleeve gastrectomy (SG). Objectives: To better characterize bone metabolism changes after SG. Setting: Systematic review and meta-analysis. Methods: MEDLINE and EMBASE were searched through March 2019 for eligible studies assessing adults with obesity aged 18 years or older that underwent SG. Bone mineral density (BMD), serum calcium, serum phosphate, serum 25-hydroxyvitamin D, serum parathyroid hormone, or serum alkaline phosphatase were reported at baseline and after SG; and a follow-up duration was at least 6 months. Preoperative and postoperative mean of each outcome of interest and corresponding standard deviations were extracted from each study and the mean difference (MD) was calculated. Pooled MD was then calculated by combining MDs of each study using random-effects model. Results: A total of 22 studies with 1905 patients with obesity that underwent SG were included. There were significant decreases in total hip BMD (pooled MD of - .06 g/cm(2); 95% confidence interval -.09 to - .03; I-2 = 0%) and femoral neck BMD (pooled MD of - .05 g/cm(2); 95% confidence interval - .09 to - .02; I-2 = 0%) after SG. No significant change in lumbar spine BMD was observed. There were significant increases in serum calcium, serum 25-hydroxyvitamin D, and serum phosphate. Serum parathyroid hormone was significantly decreased. Serum alkaline phosphatase was not significantly altered after SG. Conclusions: The present study found a decreased BMD among patients with obesity after SG. (C) 2019 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.