Article

Visceral Fat Is Associated with Lower Brain Volume in Healthy Middle-Aged Adults

Department of Neurology, Boston University School of Medicine, MA, USA.
Annals of Neurology (Impact Factor: 9.98). 08/2010; 68(2):136-44. DOI: 10.1002/ana.22062
Source: PubMed

ABSTRACT

Midlife obesity has been associated with an increased risk of dementia. The underlying mechanisms are poorly understood. Our aim was to examine the cross-sectional association of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and computed tomography (CT)-based measurements of subcutaneous (SAT) and visceral (VAT) adipose tissue with various magnetic resonance imaging (MRI) markers of brain aging in middle-aged community adults.
Participants from the Framingham Offspring cohort were eligible if in addition to having measurements of BMI, WC, WHR, SAT, and VAT, they had undergone a volumetric brain MRI scan with measurements of total brain volume (TCBV), temporal horn volume (THV), white matter hyperintensity volume (WMHV), and MRI-defined brain infarcts (BI). All analyses were adjusted for age, sex, and time interval between abdominal CT and brain MRI.
In a sample of 733 community participants (mean age, 60 years; 53% women), we observed an inverse association of BMI (estimate by standard deviation unit +/- standard error = -0.27 +/- 0.12; p = 0.02), WC (-0.30 +/- 0.12; p = 0.01), WHR (-0.37 +/- 0.12; p = 0.02), SAT (-0.23 +/- 0.11; p = 0.04), and VAT (-0.36 +/- 0.12; p = 0.002) with TCBV, independent of vascular risk factors. The association between VAT and TCBV was the strongest and most robust, and was also independent of BMI (-0.35 +/- 0.15; p = 0.02) and insulin resistance (-0.32 +/- 0.13; p = 0.01). When adjusting for C-reactive protein levels, the associations were attenuated (-0.17 +/- 0.13; p = 0.17 for VAT). No consistently significant association was observed between the anthropometric or CT-based abdominal fat measurements and THV, WMHV, or BI.
In middle-aged community participants, we observed a significant inverse association of anthropometric and CT-based measurements of abdominal, especially visceral, fat with total brain volume.

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    • "Previous studies focused on middle aged participants or were conducted in relatively small study populations. For example, Debette et al. showed that total brain volume is inversely associated with CT-measured visceral adiposity (Debette et al., 2010) and with waist-to-hip ratio (Debette et al., 2011). Kurth et al. investigated the effect of waist circumference and BMI on the gray matter volume in 115 healthy, unmedicated subjects without hypertension, type II diabetes or lipid disorder (Kurth et al., 2013). "
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    • "Raschpichler et al. (2013) demonstrated in young adults reduced GM volume exclusively in cerebellar areas with increased VAT. In comparison to BMI, Debette et al. (2010) found, in a middle-aged group, the strongest negative association between VAT and total brain volume. In old subjects, higher VAT was associated with reduced hippocampal volume and enlarged ventricles compared to lower VAT (Isaac et al., 2011). "
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