Effect of the rs10767664 Variant of the Brain-Derived Neurotrophic Factor Gene on Weight Change and Cardiovascular Risk Factors in Morbidly Obese Patients after Biliopancreatic Diversion Surgery

Abstract

Background: The effect of the rs10767664 variant of the brain-derived neurotrophic factor gene on weight loss after bariatric surgery has not been evaluated. We decided to investigate the role of the rs10767664 variant on outcomes after biliopancreatic diversion surgery. Materials and Methods: A sample of 90 patients with morbid obesity without diabetes mellitus was operated. Biochemical and anthropometric evaluation were realized at basal visit and at each visit during 3 years (at 1, 2 and 3 years). Results: Initial percentage excess weight loss, body mass index, weight, waist circumference, fat mass, blood pressure, low-density lipoprotein cholesterol, total cholesterol, triglyceride levels, insulin and homeostasis model assessment for insulin resistance (HOMA-IR) improved. No differences in these changes were detected between the two genotypes (wild-type group AA vs. mutant group AT plus TT) in a dominant model. The improvement of insulin levels was lower in T-allele carriers than non-T-allele carriers (-2.8 ± 0.7 vs. -7.1 ± 0.9 UI/dl; p = 0.02). The decrease of fasting glucose (-13.4 ± 7.4 vs. -24.2 ± 5.2 mg/dl; p = 0.01) and HOMA-IR (-1.1 ± 0.3 vs. -0.5 ± 0.4 units; p = 0.02) were lower in T-allele carriers than non-T-allele carriers. Conclusion: Our data showed an association between the rs10767664 variant and metabolic response after weight loss. Non-T-allele carriers have a better improvement in glucose, insulin and HOMA-IR levels than T-allele carriers.