Interpretation of laboratory results after gastric bypass surgery: the effects of weight loss and time on 30 blood tests in a 5-year follow-up program

Background: Long-term follow-up with blood tests is essential for bariatric surgery to be a successful treatment for obesity and related co-morbidities. Adverse effects, deficiencies, and metabolic improvements need to be controlled. Objective: We investigated the effects of time and weight loss on laboratory results in each postoperative phase after laparoscopic Roux-en-Y gastric bypass (LRYGB). Setting: Bariatric center of excellence, general hospital, Netherlands. Methods: We retrospectively evaluated results of 30 blood tests, preoperatively and at 6 months, 1 year, 2 years, and 5 years after LRYGB. The 2019 Dutch bariatric chart was used to define weight loss responses as outstanding (>p[percentile curve]+1 SD), average (p+1 SD to p-1 SD), and poor (

Automated summary

Long-term follow-up and blood tests are crucial for successful bariatric surgery in treating obesity. The study found that time and weight loss have effects on laboratory results after surgery.