Bariatric surgery leads to more rapid and greater weight loss (WL) compared to medical weight loss (MWL), but differences in body composition changes for these methods of WL remain unclear. Due to the known health risks associated with central adiposity, we sought to understand if changes in regional distribution of fat mass (FM) and lean mass (LM) differ by surgical vs. medical WL. This 1:1:1 randomized trial among 15 persons with type 2 diabetes and BMI 30-39.9 kg/m2 compared changes in body composition (measured by dual energy x-ray absorptiometry) at the time of 10% WL (or nine months after intervention) for patients receiving MWL, adjustable gastric banding (AGB), or Roux-en-Y gastric bypass (RYGB). We used non-parametric tests to evaluate differences across all arms and to compare AGB to RYGB. We present results for the 12 participants who received the study intervention and completed follow-up. All participants were women, and 75% were African American. Time to 10% weight loss was shorter for AGB and RYGB. Total FM losses were similar across arms. While differences across arms were not statistically significant, the AGB arm tended to have greater total LM and peripheral FM losses.

In conclusion, at similar overall WL, AGB may lead to preferential loss of peripheral FM and total LM. The change in total FM and truncal FM were similar across all three groups. Larger studies are needed to confirm these findings.

  MWL AGB RYGB PALL PAGB vs. RYGB 
N   
Age (Years, Mean) 46 54.3 51.5   
Mean BMI, Kg/m2      
Baseline 37.1 35.5 35   
Final 35 32 31.6   
Weight, Kg 
Baseline 104.7 96.3 94.4   
Final 98.2 86.9 85.4   
% Change -6.1 -9.8 -10.0 0.038 1.0 
Time to 10% Weight Loss, months 7.47 2.77 2.51 0.038 0.77 
Body Composition Outcomes 
Total Fat Mass, Kg      
Baseline 50.0 43.0 44.5   
Final 45.5 37.7 38.9   
% Change -8.5 -12.0 -12.9 0.67 1.0 
Truncal Fat Mass, Kg      
Baseline 24.4 24.7 24.2   
Final 21.7 22.0 20.4   
% Change -11.0 -10.9 -16.3 0.67 0. 77 
Peripheral Fat Mass, Kg      
Baseline 24.2 17.0 19.2   
Final 22.6 14.4 17.3   
% Change -5.0 -15.0 -8.7 0.67 0.56 
Lean Mass, Kg      
Baseline 53.2 51.5 46.9   
Final 50.4 44.9 43.3   
% Change -5.2 -12.4 -7.3 0.07 0.15 
  MWL AGB RYGB PALL PAGB vs. RYGB 
N   
Age (Years, Mean) 46 54.3 51.5   
Mean BMI, Kg/m2      
Baseline 37.1 35.5 35   
Final 35 32 31.6   
Weight, Kg 
Baseline 104.7 96.3 94.4   
Final 98.2 86.9 85.4   
% Change -6.1 -9.8 -10.0 0.038 1.0 
Time to 10% Weight Loss, months 7.47 2.77 2.51 0.038 0.77 
Body Composition Outcomes 
Total Fat Mass, Kg      
Baseline 50.0 43.0 44.5   
Final 45.5 37.7 38.9   
% Change -8.5 -12.0 -12.9 0.67 1.0 
Truncal Fat Mass, Kg      
Baseline 24.4 24.7 24.2   
Final 21.7 22.0 20.4   
% Change -11.0 -10.9 -16.3 0.67 0. 77 
Peripheral Fat Mass, Kg      
Baseline 24.2 17.0 19.2   
Final 22.6 14.4 17.3   
% Change -5.0 -15.0 -8.7 0.67 0.56 
Lean Mass, Kg      
Baseline 53.2 51.5 46.9   
Final 50.4 44.9 43.3   
% Change -5.2 -12.4 -7.3 0.07 0.15 

Abbreviations: MWL: medical weight loss, AGB: adjustable gastric band, RYGB: Roux-en-Y gastric bypass, BMI: body mass index

PALL for comparison across groups using Kruskal-Wallis test

PAGB vs RYGB represents comparison of AGB to RYGB group using Wilcoxon-Mann-Whitney test

Disclosure

S. Varma: None. T. Brown: Advisory Panel; Self; Merck & Co., Inc.. J. Clark: None. N. Maruthur: None. M. Schweitzer: Consultant; Self; Ethicon US, LLC.. T. Magnuson: None. C. Lee: None.

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