No abstract

Sleeve gastrectomy (SG) is effective in treating cardiometabolic complications of obesity but is associated with bone loss. Our aim was to determine the effect of SG on the lumbar spine by biomechanical CT analysis in adolescents/young adults with obesity. We hypothesized that SG would lead to a decrease in strength and bone mineral density (BMD) compared with nonsurgical controls. In a 12‐month prospective nonrandomized study, adolescents/young adults with obesity underwent SG (n = 29, 18.0 ± 2.1 years, 23 female) or were followed without surgery (controls, n = 30, 17.95 ± 3.0 years, 22 female). At baseline and 12 months, participants underwent quantitative computed tomography (QCT) of L1 and L2 for biomechanical assessment and MRI of the abdomen and mid‐thigh for body composition assessment. Twelve‐month changes between groups and within groups were assessed. Analyses were controlled for baseline and 12‐month changes in body mass index (BMI) by multivariable analyses. Regression analysis was performed to evaluate the effect of body composition on bone parameters. Our institutional review board (IRB) approved the study, and informed consent/assent was obtained. Participants in the SG group had a higher baseline BMI than controls (p = 0.01) and lost an average of 34.3 ± 13.6 kg 12 months after surgery, whereas weight was unchanged in controls (p < 0.001). There were significant reductions in abdominal adipose tissue and thigh muscle area in the SG group compared with controls (p < 0.001). Bone strength, bending stiffness, and average and trabecular volumetric BMD decreased in the SG group compared with controls (p < 0.001). After controlling for change in BMI, a 12‐month reduction in cortical BMD was significant in the SG group compared with controls (p = 0.02). Reductions in strength and trabecular BMD were associated with reductions in BMI, visceral adipose tissue, and muscle (p ≤ 0.03). In conclusion, SG in adolescents decreased strength and volumetric BMD of the lumbar spine compared with nonsurgical controls. These changes were associated with decreases in visceral fat and muscle mass. © 2023 American Society for Bone and Mineral Research (ASBMR).

Context Obesity is associated with non-alcoholic fatty liver disease (NAFLD). Sleeve gastrectomy (SG) is an effective means of weight loss and improvement of NAFLD in adults; however, data regarding the efficacy of SG in the early stages of pediatric NAFLD are sparse. Objective To assess the impact of SG on hepatic fat content one year after SG in youth with obesity compared with non-surgical controls with obesity (NS). Design 12-month prospective study in 52 participants [mean age: 18.2 ± 0.36 years] with obesity, comprising 25 subjects who underwent SG [84% female; median BMI 44.6 (42.1, 47.9) kg/m2], and 27 who were NS [70% female; median BMI 42.2 (38.7, 47.0) kg/m2]. Main outcome measures Hepatic fat content by CT (liver/spleen ratio), abdominal fat by MRI Results Mean 12-month decrease in BMI was greater in SG vs. NS (-12.5±0.8 vs. -0.2±0.5 kg/m2, p&lt;0.0001). There was a within-group increase in the L/S ratio in SG (0.13± 0.05, p=0.014) but not NS with a trend for a difference between groups (p=0.055). All SG participants with an L:S ratio &lt;1.0 (threshold for the diagnosis of NAFLD) before surgery had a ratio of &gt;1.0 a year after surgery, consistent with resolution of NAFLD. Within SG, the 12-month change in L/S ratio was negatively associated with 12-month change in visceral fat (ρ=-0.51 p=0.016). Conclusions Hepatic fat content as assessed by non-contrast CT improved after SG over 1-year in youth with obesity with resolution of NAFLD in all subjects. This was associated with decreases in visceral adiposity.