Kimberly Smith, PhD1, Afroditi Papantoni, BS1, Marga Veldhuizen, PhD2, Timothy Moran, PhD1, Susan Carnell, PhD1, Kimberley E Steele, MD, PhD1. 1The Johns Hopkins University School of Medicine, 2Yale University, The John B Pierce Laboratory, Inc
Background: Changes in taste preferences have been reported following bariatric surgery. To investigate neural mechanisms for such changes and differentiation by surgery type, we measured behavioral and neural responsiveness to varying concentrations of sugar and fat-containing tastants in patients before and 2 weeks after vertical sleeve gastrectomy (VSG) or Roux-en Y gastric bypass (RYGB).
Methods: Prior to surgery, patients were presented with 12 taste stimuli varying in sugar and fat content and asked each patient to rate each stimulus on a visual analog scale and select the stimulus they preferred most. Patients then underwent a functional magnetic resonance imaging (fMRI) brain scan in which they were orally presented with the following stimuli in a randomized order across multiple trials: high fat (cream, 0% added sugar), high sugar (skim milk, 20% added sugar), the patient’s most preferred tastant, and a tasteless solution. Two weeks following bariatric surgery, patients repeated the taste preference test and fMRI.
Results: A total of 34 patients (VSG; N=17 and RYGB; N=17) participated prior to and two weeks following bariatric surgery. The mean pre-surgical BMI for VSG (42.36, SD 4.43) and RYGB (43.52, SD 3.68); 2 weeks mean post surgery BMI VSG (39.77, SD 3.89) and RYGB (40.64, SD 3.90). Initial whole-brain analyses indicate increased blood-oxygen-level dependent (BOLD) responses in the insula and amygdala to the high fat and high sugar solutions, respectively, in RYGB patients relative to VSG patients 2 weeks following surgery. Greater post-surgical decreases in BOLD responses in the insula and striatum to the patients’ pre-surgical most preferred solution were seen in RYGB patients relative to VSG patients.
Conclusion: Our preliminary data suggest that bariatric surgery may decrease preferences for high energy-dense foods by modulating brain reward responses to combined tastes of sugar and fat, and that the extent of changes in taste-responsive neural activation may differ by surgery type (supported by 1K23DK100559).
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 95496
Program Number: P176
Presentation Session: Poster Session (Non CME)
Presentation Type: Poster