Is Fat Mass Cross-Sectionally Associated with Cortical Aβ Load in the Human Brain?

The objective of this study was to examine the relationship of fat mass (FM) with brain amyloid (Aβ) load in older adults.

Data from the Multidomain Alzheimer's Preventive Trial (MAPT) for Positron emission tomography and dual-energy X-ray absorptiometry (DXA) were used. Linear regressions controlling for appendicular muscle, age, education, clinical dementia rating scale and Apolipoprotein-E were performed to explore the relationships between FM, trunk FM and Aβ-load.

Thirty-nine participants (75.7 ± 4.2 years old) with an average BMI of 27.5 ± 4.0 kg/m2 were analyzed in this study. There were significant and positive associations of both total and trunk FM with Aβ load [0.01 (0.002-0.02) and 0.02 (0.001-0.04), respectively]; however, when adding ApoE-ε4 as a confounder, associations were no longer significant.

This study has found associations between FM as measured by DXA and cerebral Aβ load, suggesting that excessive FM might be involved in AD pathology.