Premium
BMI and Body Fat Mass Are Differentially Associated with fMRI Food‐cue Reactivity in Individuals with Obesity
Author(s) -
Quarles William R,
Kahathuduwa Chanaka Nadeeshan,
Davis Tyler,
O'Boyle Michael,
Binks Martin
Publication year - 2017
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.31.1_supplement.797.10
Subject(s) - body mass index , medicine , obesity , orbitofrontal cortex , magnetic resonance imaging , functional magnetic resonance imaging , audiology , psychology , radiology , cognition , psychiatry , prefrontal cortex
Background Body Mass Index (BMI) is commonly used to categorize obesity in fMRI research. However, BMI fails to fully account for variability of body composition among individuals (e.g. body fat mass; BFM). Given that adipose tissue produces several hormones received by the brain to affect ingestive behavior, it is important to understand how BMI and BFM may be differentially associated with food‐cue reactivity in the brain. Objective To examine the association between both BMI and BFM with brain functional magnetic resonance imaging (fMRI) food‐cue reactivity (FCR). Methods Baseline data of 32 subjects (age 19–65 yrs.; BMI 30–39.9kg/m 2 ) was used from a larger study. BMI was calculated from measured height and weight and BFM was measured using bio‐electrical impedance. During the fMRI scan, subjects were shown 240 images (120 food and 120 objects) in an event‐related paradigm. Using the median BMI and BFM as the cut score, subjects were categorized into 2 groups (high and low), for both BMI and BFM. FMRI analyses were conducted on 3 levels in FSL to compare FCR: high BMI vs. low BMI and high BFM vs. low BFM. Results FMRI analysis revealed increased FCR in the high BMI compared to low BMI group in the bi‐lateral insular cortices. Increased FCR was seen in high BFM compared to low BFM group in the bilateral precuneus, left angular gyrus, left supramarginal gyrus, right orbitofrontal cortex, right nucleus accumbens, and the right temporal pole. Conclusion FCR was greater in both high BMI and high BFM groups compared with low BMI and low BFM groups. However the brain regions involved were different in each. These differences in FCR between BMI and BFM suggest a lack of concordance among these methods for delineating degree of obesity that may influence interpretation of fMRI FCR data. Given that BFM is more closely aligned physiologically with ingestion, it may be prudent to use BFM, not BMI, in fMRI FCR studies of obesity and ingestive behavior. Support or Funding Information Funding: Nestle Health Science.