Work

Longitudinal analysis of body compositions following Roux-en-Y gastric bypass

Year: 2026

Type: article

Abstract: BACKGROUND: Roux-en-Y gastric bypass (RYGB) is associated with substantial weight loss and improved obesity-related comorbidities. However, outcomes on body composition, particularly skeletal muscle (SM), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) remain inconsistent due to limitations in measurement techniques. OBJECTIVE: Evaluate longitudinal changes in SM, VAT, and SAT volumes (cm3) following RYGB using Data Analysis Facilitation Suite (DAFS), an automated computed tomography (CT) analysis software. METHODS: In this prospective pilot study, nine female patients underwent low-dose abdominal and pelvic CT imaging at baseline, 3-, and 6-months post-RYGB. Volumetric analysis from the ninth thoracic veterbra (T9) to the sacrum was performed using DAFS. Changes in SM, VAT, and SAT were assessed using paired t-tests. RESULTS: Participants (mean ± SD; age 35 ± 9 years, BMI 48 ± 10 kg/m²) experienced substantial weight loss (14 ± 5% at 3 months, 25 ± 7% at 6 months; p < 0.001). SAT and VAT volumes decreased significantly by 21% and 27% at 3 months, and by 31% and 47% at 6 months, respectively (all p < 0.001). In contrast, SM volume showed a significant decline of 14% at month 3 (p < 0.001) and then plateaued thereafter. CONCLUSION: The changes over time differ substantially among SM, VAT and SAT after Roux-en-Y gastric bypass, reflecting the distinct physiological responses and metabolic improvement of different tissue types. Larger and longer clinical studies are needed to validate these findings.

Source: Langenbeck s Archives of Surgery

DOI: 10.1007/s00423-026-03994-8