Patient characteristics.

Outpatient nutritional counseling by a registered dietitian is often performed to prevent weight loss, but evidence supporting this practice is insufficient. In this study, we aimed to clarify the effectiveness of four-time outpatient nutritional counseling in weight-loss prevention compared with conventional intervention limited to one-time nutritional counseling. This study was designed as a retrospective cohort study. The target population was postoperative patients with stage IA and IB gastric cancer. Groups that received one-time and four-time nutritional counseling included patients who underwent gastrectomy from May 2014 to April 2017 and May 2017 to December 2019, respectively. The one-time group received counseling at discharge; the four-time group received counseling at discharge, at the first outpatient visit, and at 3 and 6 months postoperatively. There were 58 patients in the one-time group and 27 patients in the four-time group, with a significant difference in length of hospital stay (p = 0.042). Thirty-six patients (62.1%) in the one-time nutritional counseling group and 12 (44.4%) in the four-time group had a weight loss of 5% or more from hospital discharge to 6 months postoperatively. The adjusted risk ratio for the effectiveness of four counseling sessions compared with one session was 0.69 (95% confidence interval 0.35–1.34). In subgroup analysis, the effect of nutritional guidance was greater for patients with body mass index ≥23 kg/m2, but this depended on the outcome and number of cases, and there was no essential difference between the groups. In postoperative patients with stage IA and stage IB gastric cancer, four sessions of outpatient nutrition counseling may be not superior to one counseling session in preventing weight loss.