Postoperative changes in body composition after gastrectomy.

Nutritional status is one of the most important clinical determinants of outcome after gastrectomy. The aim of this study was to compare changes in the body composition of patients undergoing laparoscopy-assisted gastrectomy (LAG), distal gastrectomy (DG), or total gastrectomy (TG). Total body protein and fat mass were measured by performing a multifrequency bioelectrical impedance analysis using an inBody II machine (Biospace, Tokyo, Japan) in 108 patients (72 men, 36 women) who had undergone LAG (n=24), DG (n=39), or TG (n=45). Changes between the preoperative data and results obtained on postoperative day 14 and 6 months after surgery were then evaluated. The mean preoperative body weight of the subjects was 57.6+/-10.7 kg, the mean body mass index was 22.5+/-3.4 kg/m(2), and the mean fat % was 24%+/-7%. In the immediate postoperative period (14 days), the body weight loss in the LAG group was significantly lower than in the DG and TG groups (2.5+/-0.9 kg vs. 3.5+/-1.8 kg and 4.0+/-1.9 kg, respectively; P < 0.0001). The body composition studies demonstrated a loss of total body protein rather than fat mass. Six months after surgery, body weight was not significantly different from preoperative values in the LAG and DG groups (-1.2+/-3.8 kg and -1.8+/-4.7 kg, respectively), but had decreased by 8.9+/-4.9 kg in the TG group (P=0.0003). A body composition analysis revealed a loss of fat mass in the DG and TG groups. The patients who underwent gastrectomy lost body protein mass during the early postoperative period. The type and extent of surgery has an effect on long-term body mass and composition. Bioelectric impedance analysis can be used to assess body composition and may be useful for nutritional assessment in patients who have undergone gastrectomy.