Body Fat Distribution as a Risk Factor for Cerebrovascular Disease: An MRI-Based Body Fat Quantification Study

Abstract

Background: While adiposity is a well-established risk factor for cardiovascular disease, the association between adiposity and cerebrovascular disease is not entirely understood. For example, common methods to quantify body fat volume such as body mass index, waist circumference and waist-to-hip ratio are not suitable to identify the complex distribution patterns of body fat and its relation to cerebrovascular pathology. In view of a better understanding of the association between fat distribution and cerebrovascular disorders, the aim of the study was to perform measurements of body fat distribution patterns and body fat volumes in correlation to arteriosclerosis of the brain-feeding arteries and white matter lesion load (WMLL). Methods: In this study we performed a magnetic resonance imaging (MRI)-based volumetric differential analysis of subcutaneous and visceral body fat distribution in 25 patients with MRI-proven hyperacute ischemic stroke. For the measurement of adipose tissue volume and tissue distribution automatic labeling analysis software was used. A correlation analysis of MRI volumetric measurements of subcutaneous and visceral body fat, atherosclerotic plaque load of the brain-feeding arteries measured by computed tomography angiography, and WMLL measured by MRI volumetry of the whole brain was performed. Results: The normalized total abdominal adipose tissue and the normalized subcutaneous abdominal adipose tissue showed no significant correlation with either WMLL or total plaque volume. In contrast, the normalized visceral adipose tissue showed a significant correlation with WMLL volume. Visceral adipose tissue as a percentage of total adipose tissue showed a significant correlation with WMLL. In particular, the percentage of visceral adipose tissue rather than total body fat volume strongly correlated with atherosclerosis and ischemic cerebral lesions. Furthermore, the volume of both soft and calcified plaques correlated significantly with WMLL. Conclusions: Our results contribute to existing studies about the association of different patterns of fat distribution with atherosclerosis of the brain-feeding arteries, in particular highlighting the importance of visceral adiposity as a risk factor for cerebrovascular disease. The percentage of visceral adipose tissue in total adipose tissue has the potential of a sensitive parameter and might become a relevant new epidemiological marker, showing highly significant correlations with well-established markers of cerebrovascular disease. In conclusion, the percentage of visceral adipose tissue by itself has to be regarded as a risk factor for both small vessel cerebrovascular disease and cerebral atherosclerosis of the large-to-medium-sized arteries.

Risk Factors Assessed in Adolescence and the Later Risk of Stroke in Men: A 33-Year Follow-Up Study

“…Similarly, those in the lowest compared to the highest 10% of aerobic fitness were found to have a 70% increased risk of ischemic stroke, while the risk was more than doubled for hemorrhagic stroke. Several previous studies have linked BMI and visceral adiposity, and aerobic fitness, to clinical manifestations of atherosclerotic disease, but predominantly in older populations and for the outcomes of cardiovascular disease and death [21,22,23,24]. The results of the present study indicate that classic risk factors for atherosclerotic disease assessed already in adolescence contribute substantially to an increased risk of stroke.…”

Visceral Fat Is an Independent Predictor of Cerebral Microbleeds in Neurologically Healthy People

“…Nagura et al [26] reported that extreme accumulation of visceral fat as measured by abdominal CT was more likely associated with lacunar infarcts. Other CT-based studies have suggested that visceral fat accumulation was related to the presence of white matter hyperintensities and silent lacunar infarction on brain MRI [9,10,27] . However, whether this association was mediated by adiposity-related risk factors for cerebral small vessel diseases, such as hypertension or dia- Recent studies have demonstrated that VAT accumulation was positively associated with cardiovascular diseases [10,28,29] and that VAT produces large amount of interleukin-6 and by doing so promotes the secretion of C-reactive protein, inflammatory markers, and adipocytokines [14,30] .…”

“…On the other hand, peripheral subcutaneous fat may be protective in nature with respect to cardiovascular diseases [31] . Therefore, the percentage of VAT in total adipose tissue has recently been proposed as having the potential as a sensitive parameter showing highly significant correlations with the markers of cardiovascular disease [10] . The strength of our study was that we used abdominal CT for measuring abdominal fat distribution in subjects who underwent brain MRI; therefore, we could demonstrate that VAT/SAT ratio has potential as a new epidemiological predictor of CMB in neurologically healthy people.…”

“…These obesity-related clinical risks are known to be mediated by different regional fat distribution such as visceral and subcutaneous adiposity [8] . According to recent papers, visceral adipose tissue (VAT) is associated with the presence of various markers of cerebral small vessel disease including white matter disease volume and silent lacunar infarct [9,10] . When viewed from this perspective, little is known about the association of central adiposity and the presence of CMBs.…”

Visceral adipose tissue inflammation is associated with age-related brain changes and ischemic brain damage in aged mice

“…These studies indicate that visceral adiposity induces structural and functional changes in the brain. Furthermore, brain imaging studies in individuals with or without stroke history suggest that visceral adiposity can be a risk factor for cerebrovascular diseases, because visceral fat accumulation and an increased ratio of visceral adipose tissue to total adipose tissue strongly correlate with white matter lesions and ischemic lesions (Karcher et al, 2013;Nagura et al, 2004;Yamashiro et al, 2014). In addition to being a risk factor, visceral adiposity may have an influence on brain damage following acute ischemic insult, especially in the aged brain.…”