Increasing Body Mass Index in an Elderly Cohort: Effects on the Quantitative MR Parameters of the Brain
09 July 2019
The obesity epidemic, as it has become to be known as, affects millions of people worldwide, particularly in industrialised countries and, increasingly, among the elderly population. Although an elevated BMI is known to be associated with a wide range of health problems, less is known about how an increased BMI may affect the brain in old age.
The purpose of this study was to investigate the relationship between BMI and quantitative water content, T1, T2*, and the semi-quantitative magnetization transfer ratio (MTR) of various structures in the brains of elderly subjects. Forty-two adults (BMI range: 19.1–33.5 kg/m2, age range: 58–80 years) were scanned using an MRI machine with a field strength of 3T.
It was found that T1 was significantly increased (P < 0.05) in the frontal, temporal, and parietal cortices, while the bilateral corona radiata, right superior longitudinal fasciculus, as well as the corpus callosum showed significant changes in the WM regions. T2* was found to be significantly increased in the global WM and left corona radiata. Changes in MTR and the free water content did not reach significance, and no significant correlation between any quantitative parameter and the lipid spectra or CRP could be identified.
By measuring quantitative parameters derived from MRI, the results show that both WM and GM structures were affected by an increased BMI in this elderly cohort. Due to their demonstrated sensitivity, it is anticipated that the presented (semi)quantitative parameters might be used as an early diagnostic tool for the detection of brain changes caused by an increasing BMI.