Association of changes in appendicular skeletal muscle mass with weight loss and visceral fat reduction after laparoscopic sleeve gastrectomy

Laparoscopic sleeve gastrectomy (LSG) drastically affects body composition. However, studies focusing on the association between the changes in the pre-and postoperative muscle mass and postoperative results are limited. We evaluated the association between changes in the muscle mass and weight loss and fat reduction.

This retrospective study included 29 consecutive patients who underwent both LSG and a bioelectrical impedance analysis (BIA) consecutively. We investigated changes in the body composition on the BIA and visceral fat area (VFA) on computed tomography and correlational changes in muscle mass with weight loss and fat reduction.

The total weight loss (%TWL) 12 months after surgery was 30.9%. The VFAs pre- and postoperatively were 224 and 71.0 cm², respectively. The fat mass (FM), percentage of FM, appendicular skeletal muscle mass (ASM), and skeletal muscle mass index (SMI) decreased from pre- to postoperatively (54.8 vs. 32.2 kg; 49.0 vs. 41.2%, 26.7 vs. 23.9 kg, 9.24 vs. 8.27, respectively), whereas the percentage of ASM (%ASM) increased (22.1 vs. 28.0%). The rate of change in %ASM positively correlated with weight loss and fat reduction (%TWL, rs = 0.65; %VFA loss, rs = 0.62).

The rate of change in %ASM was positively correlated with weight loss and fat reduction.