Changes in Bone Marrow Adipose Tissue One Year After Roux-en-Y Gastric Bypass: A Prospective Cohort Study

J Bone Miner Res. 2019 Oct;34(10):1815-1823. doi: 10.1002/jbmr.3814. Epub 2019 Aug 7.

Abstract

Bone marrow adipose tissue (BMAT) has been postulated to mediate skeletal fragility in type 2 diabetes (T2D) and obesity. Roux-en-Y gastric bypass (RYGB) induces a substantial weight loss and resolution of comorbidities. However, the procedure induces increased bone turnover and fracture rates. No previous study has evaluated biopsy-measured BMAT fraction preoperatively and after RYGB. In this study, we aimed to investigate BMAT fraction of the hip in participants with and without T2D preoperatively and 1 year after RYGB and explore factors associated with BMAT change. Patients with morbid obesity scheduled for RYGB were examined preoperatively and 1 year after RYGB. Forty-four participants were included and preoperative examinations were possible in 35. Of these, 33 (94%) met for follow-up, 2 were excluded, and BMAT estimation was not possible in 1. Eighteen (60%) of the participants were females and 11 (37%) had T2D. Preoperative BMAT fraction was positively associated with glycosylated hemoglobin and negatively associated with areal bone mineral density (aBMD). After RYGB, BMAT fraction decreased from 40.4 ± 1.7% to 35.6 ± 12.8%, p = 0.042, or with mean percent change of 10.7% of preoperative BMAT fraction. Change in BMAT fraction was positively associated with change in body mass index (BMI) and total body fat. In females, we observed a mean percent reduction of 22.4 ± 19.6%, whereas in males BMAT increased with a mean percent of 6.8 ± 37.5%, p = 0.009. For males, changes in estradiol were associated with BMAT change; this was not observed for females. In participants with and without T2D, the mean percent BMAT reduction was 5.8 ± 36.9% and 13.5 ± 28.0%, respectively, p = 0.52. We conclude that a high BMAT seems to be associated with lower aBMD and poorer glycemic control in obese subjects. After RYGB, we observed a significant decrease in BMAT. The reduction in BMAT did not differ between participants with and without T2D, but appeared sex specific. © 2019 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc.

Keywords: BONE MARROW ADIPOSE TISSUE; BONE MARROW FAT; BONE MINERAL DENSITY; MORBID OBESITY; ROUX-EN-Y GASTRIC BYPASS; WEIGHT LOSS.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue* / metabolism
  • Adipose Tissue* / pathology
  • Adult
  • Bone Marrow* / metabolism
  • Bone Marrow* / pathology
  • Diabetes Complications* / metabolism
  • Diabetes Complications* / pathology
  • Diabetes Complications* / surgery
  • Diabetes Mellitus, Type 2* / metabolism
  • Diabetes Mellitus, Type 2* / pathology
  • Diabetes Mellitus, Type 2* / surgery
  • Female
  • Follow-Up Studies
  • Gastric Bypass*
  • Hip Fractures* / metabolism
  • Hip Fractures* / pathology
  • Humans
  • Male
  • Middle Aged
  • Norway
  • Obesity, Morbid* / metabolism
  • Obesity, Morbid* / pathology
  • Obesity, Morbid* / surgery
  • Prospective Studies
  • Time Factors