Selected factors affecting the rate of reduction of body weight components during the first six months after bariatric surgery: cohort study

Purpose: To determine whether the rate of slimming following bariatric surgery depends on the sex, type of bariatric surgery, time elapsed from surgery and body weight components.Materials and methods: The material comprises the results of three series of anthropometric measurements in 91 obese patients (before bariatric surgery, after about 3 months and after about 6 months from bariatric surgery). Inclusion criteria: all patients of Polish origin who were admitted to hospital from July 1, 2017 to January 31, 2019 for the purpose of surgical treatment of obesity, and who expressed written consent for surgery and participation in the study. Measurements included: body weight components assessed by electric bioimpedance metod. Results: Reduction of all features was higher after SG than GB (p<0.0001), higher in the first quartile than in the secondo quartile after surgery (p<0.0001) and higher for fat mass than for other components of body weight (p<0.0001). Sex of patients, type of bariatric surgery, time elapsed from operation and type of body weight component constitute interactive modifiers of the reduction rate.Conclusion: After bariatric surgery the reduction of fat mass is quicker in men than in women. SG and RYGB lead to higher reduction of fat mass GB. Only after SG among all three analyzed operative procedures the rate of body weight components reduction does not decrease in the second quartile after surgery. The above information should be taken into account when creating an algorithm for handling a patient after bariatric surgery.