Effective treatment improves the body composition of patients with esophageal motility disorders.

Although treatment for esophageal motility disorder improves dysphagia and increases body weight, the effect of the treatment on body composition is unclear. This study aimed to assess the change in body composition between before and after treatment, the preoperative predictors of muscle increase, and the association between muscle increase and quality of life. Sixty-one patients (achalasia, n = 55; spastic esophageal disorder n = 6) who underwent per-oral endoscopic myotomy were analyzed in a single-arm prospective observational study. Appendicular skeletal muscle mass was measured with dual X-ray absorptiometry before and 3 months after per-oral endoscopic myotomy. For subgroup analysis, patients with postoperative appendicular skeletal muscle mass increase were defined as the muscle-increase group and the rest as the non-muscle-increase group. Preoperative factors related to the muscle-increase group were clarified via multivariate analysis. Further, the improvement after per-oral endoscopic myotomy in health-related quality-of-life score (Short Form-36) was compared between the muscle-increase and non-muscle-increase groups. Appendicular skeletal muscle mass increased significantly 3 months after per-oral endoscopic myotomy (P = 0.0002). The patients who underwent effective treatment (postoperative Eckardt score < 3) showed a significant improvement in appendicular skeletal muscle mass compared to those who did not (P = 0.04). In the stepwise logistic regression analysis, the preoperative Eckardt score (odds ratio: 1.95, 95% confidence interval 1.30-3.26, P = 0.0005) and preoperative serum prealbumin (odds ratio: 0.83, 95% confidence interval 0.70-0.97, P = 0.02) were identified as independent factors related to postoperative muscle increase. The improvements in the Short Form-36 domains of General Health (P = 0.0007) and Vitality (P = 0.003) were significantly higher in the muscle-increase group. The findings show that effective treatment improved the body composition of patients with esophageal motility disorder and that the Eckardt score and serum prealbumin may aid the prediction of increased appendicular skeletal muscle mass after treatment, resulting in a better quality of life.