Research Paper Volume 11, Issue 19 pp 8573—8586
High body mass index, brain metabolism and connectivity: an unfavorable effect in elderly females
- 1 Vita-Salute San Raffaele University, Milan, Italy
- 2 In vivo Human Molecular and Structural Neuroimaging Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
- 3 Metabolism Research Center and Endocrinology and Metabolism Division, IRCCS Policlinico San Donato, Milan, Italy
- 4 Nuclear Medicine Unit, IRCCS San Raffaele Hospital, Milan, Italy
- 5 Università degli Studi di Milano, Milan, Italy
Received: March 17, 2019 Accepted: September 27, 2019 Published: October 9, 2019
https://doi.org/10.18632/aging.102347How to Cite
Copyright © 2019 Sala et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
There are reported gender differences in brain connectivity associated with obesity. In the elderlies, the neural endophenotypes of obesity are yet to be elucidated. We aim at exploring the brain metabolic and connectivity correlates to different BMI levels in elderly individuals, taking into account gender as variable of interest.
We evaluated the association between BMI, brain metabolism and connectivity, in elderly females and males, by retrospectively collecting a large cohort of healthy elderly subjects (N=222; age=74.03±5.88 [61.2-85.9] years; M/F=115/107; BMI=27.00±4.02 [19.21-38.79] kg/m2). Subjects underwent positron emission tomography with [18F]FDG. We found that, in females, high BMI was associated with increased brain metabolism in the orbitofrontal cortex (R=0.44; p<0.001). A significant BMI-by-gender interaction was present (F=7.024, p=0.009). We also revealed an altered connectivity seeding from these orbitofrontal regions, namely expressing as a decreased connectivity in crucial control/decision making circuits, and as an abnormally elevated connectivity in reward circuits, only in females. Our findings support a link between high BMI and altered brain metabolism and neural connectivity, only in elderly females. These findings indicate a strong gender effect of high BMI and obesity that brings to considerations for medical practice and health policy.