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: 11.91). 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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    • "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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    • "years) that utilized objective measures of both visceral fat and brain structure (MRI), higher visceral fat was associated with poorer verbal memory and attention as well as lower hippocampal volume (Isaac et al., 2011). These findings were supported by data from Debette and colleagues who found inverse associations between total brain volume and multiple measures of adiposity including BMI, waist circumference, waist-to-hip ratio, and objectively measured visceral adipose tissue with the strongest association visceral adipose tissue (Debette et al., 2010). Furthermore , in a longitudinal study examining the impact of objectively measured central adiposity on risk of dementia, Whitmer and colleagues found that higher central adiposity in midlife predicted dementia diagnosis 36 years later independent of diabetes and cardiovascular comorbidities (Whitmer et al., 2008). "
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