Department of Digestive Surgery, CHU Félix Guyon, Saint Denis, Saint-Étienne, France.
Physiologie Clinique et de l'Exercice, CHU Saint-Étienne, Saint-Étienne, France.
Front Endocrinol (Lausanne). 2023 May 26;14:1148068. doi: 10.3389/fendo.2023.1148068. eCollection 2023.
BACKGROUND/OBJECTIVES: Obesity is a complex health issue in which the brain plays a role yet to be determined, especially in the elderly. Indeed, in the ageing population, the balance between fat and lean mass is different; thus, the co-influence between the brain and obesity may differ between the elderly and younger subjects. Our main goal is thus to explore the relationship between the brain and obesity using two different approaches to measure obesity: body mass index (BMI) and an index centred on fat mass, the body fat index (BFI).
SUBJECTS/METHODS: Among the 1,011 subjects of the PROOF population, 273 subjects aged 75 years underwent 3D magnetic resonance imaging as well as dual-energy X-ray absorptiometry to assess fat mass. Voxel-based morphometry was used to explore the local differences in brain volume with obesity.
Higher BMI and BFI were associated with higher grey matter (GM) volume in the left cerebellum. Higher BMI and BFI were mainly associated with higher white matter volume in the left and right cerebellum and near the right medial orbital gyrus. Higher BMI was also associated with higher GM volume in the brainstem, whereas higher BFI was associated with higher GM volume in the left middle temporal gyrus. No decrease in white matter was associated with BMI or BFI.
In the elderly, the relationship between the brain and obesity does not depend on the marker of obesity. Supra-tentorial brain structures seem to be slightly associated with obesity, whereas the cerebellum seems to be one of the key structures related to obesity.
背景/目的：肥胖是一个复杂的健康问题，其中大脑的作用尚未确定，尤其是在老年人中。事实上，在老年人群中，脂肪量和瘦体量之间的平衡是不同的；因此，大脑和肥胖之间的共同影响可能在老年人和年轻人之间有所不同。我们的主要目标是使用两种不同的肥胖测量方法（体重指数（BMI）和以脂肪量为中心的指数，即体脂指数（BFI））来探讨大脑和肥胖之间的关系。
受试者/方法：在 PROOF 人群的 1011 名受试者中，有 273 名年龄为 75 岁的受试者接受了 3D 磁共振成像和双能 X 射线吸收法检查，以评估脂肪量。体素基于形态计量学用于探索肥胖与大脑体积局部差异。
较高的 BMI 和 BFI 与左侧小脑灰质（GM）体积增加有关。较高的 BMI 和 BFI 主要与左右小脑和靠近右侧内侧眶额回的白质体积增加有关。较高的 BMI 还与脑干 GM 体积增加有关，而较高的 BFI 与左侧颞中回 GM 体积增加有关。没有发现与 BMI 或 BFI 相关的白质减少。
在老年人中，大脑和肥胖之间的关系不依赖于肥胖的标志物。大脑的皮质下结构似乎与肥胖略有相关，而小脑似乎是与肥胖相关的关键结构之一。
