Weight loss before bariatric surgery and its impact on poor versus excellent outcomes at 2 years

To identify preoperative factors that influence the outcomes of gastric bypass surgery, in terms of excess weight loss at 24 months.

This retrospective study included two groups of patients who underwent laparoscopic gastric bypass surgery. Group A (poor outcomes) had ≤ 50%EWL or BMI ≥ 30 kg/m²; group B (excellent outcomes) had ≥ 80%EWL at 24 months. A comparative analysis of demography, anthropometry, comorbidities, and metabolic status was performed. A linear regression model was used to evaluate %EWL association; the number of preoperative and postoperative consultations were also compared.

A total of 202 patients completed follow-up; 71 (35.1%) and 78 (38%) had poor and excellent outcomes (%EWL 44.1 ± 9.4% vs. 92 ± 10.9%), respectively. Mean age was 40.4 ± 8.9 years. Patients with poor outcomes had higher weight and BMI, lesser preoperative %EWL, higher dyslipidemia and diabetes rates with longer periods of evolution, and increased HbA1c% levels. In the linear regression analysis, preoperative %EWL and initial and preoperative BMI were statistically significant determinants of %EWL at 24 months Diabetes remission was 46.2% (group A) vs. 66.6% (group B). Group A had higher non-attendance rates after surgery.

The factors independently associated with greater %EWL at 24 months between groups were higher preoperative %EWL, and lower initial and preoperative BMI.