Impact of sleeve gastrectomy on bone outcomes in adolescents vs. adults with obesity

Abstract Background Sleeve gastrectomy (SG) is the most common metabolic and bariatric surgery (MBS) procedure in adolescents and adults. Only few studies have assessed bone outcomes following SG and it is unknown whether skeletal changes differ by age group. Recent studies have identified marrow adipose tissue (MAT) as a novel biomarker for bone quality with studies in adults showing high MAT in those with visceral adiposity and a reciprocal increase in MAT with bone loss. Objective To determine the impact of SG on volumetric BMD (vBMD) and MAT in adolescents and adults with obesity. We hypothesized that SG would lead to a decrease in vBMD and increase in MAT but that these changes would be less pronounced in adolescents compared to adults. Materials and methods The study was IRB-approved and HIPAA-compliant. Written informed consent/assent was obtained. We examined 10 adolescents (mean age 17.8 ± 2.5 years, mean BMI 43.5 ± 5.6 kg/m2) and 10 sex, race, and BMI-matched adults (mean age 49.5 ± 13.6 years, mean BMI 43.7 ± 5.9 kg/m2), before and 12 months after SG. At baseline and 12 months, subjects underwent quantitative CT of the lumbar spine (L1−L2) to assess trabecular vBMD, single voxel proton MR spectroscopy at 3 T (PRESS pulse sequence without water suppression) at L1-L2 to quantify MAT, and MRI of the abdomen to assess visceral (VAT) and subcutaneous adipose tissue (SAT). Results At baseline, adolescents had lower MAT (p = 0.0002) and higher vBMD (p = 0.050) compared to adults. Adolescents and adults lost 27.9 ± 6.5 vs. 25.0 ± 11.2% of body weight (p  Conclusion SG in adolescents and adults with severe obesity is associated with a reduction in lumbar vBMD and an increase in lumbar MAT, although the reduction in adolescents did not reach statistical significance, with no significant differences in these endpoints between groups. Our results suggest detrimental effects of bariatric surgery on bone for patients across the life span.