RESUMO
PURPOSE: Differences in weight loss outcomes after bariatric surgery may be related to individual preoperative characteristics. The aim of this study was to evaluate the potential effect of fatty acid binding protein-2 (rs1799883), leptin receptor (LEP223, rs1137101 and LEP656, rs1805094), and fat mass and obesity-related (rs9939609) genotypes on weight loss 2 years after bariatric surgery in Brazilian patients. MATERIALS AND METHODS: Prospective observational study involving 105 patients (lost to follow-up, 25.7%). In the preoperative period, patients were clinically evaluated and a fasting blood sample for genetic analysis (by real-time DNA amplification technique) was collected. From the patient's medical records, follow-up weight loss (3, 6, 12, 24 months) was obtained. Percentage of excess weight loss (%EWL) was examined by pairwise comparison across the polymorphisms. RESULTS: At baseline, the mean weight was 127.5 (23.3) kg and age 43.1 (10.9) years old. The %EWL was significant over time (p < 0.01). Only the LEP223 genotype showed association (p < 0.01). Up to 6 months after surgery, no differences were observed. At 12 months, a significant difference (p = 0.03) between AA (n = 19) and GG (n = 34) groups was observed, with 76.5% EWL versus 52.0%, respectively. This difference remained at 24 months. Other genotypes did not present any significant association. CONCLUSIONS: There is a different evolution of weight loss in carriers of the LEP223 after bariatric surgery. The AA genotype seems to be associated with a higher weight loss. However, this pattern was evident only at 12 months after surgery.