Visceral adiposity and arterial stiffness: echocardiographic epicardial fat thickness reflects, better than waist circumference, carotid arterial stiffness in a large population of hypertensives

Relationship between obesity and cardiovascular (CV) disease depends not only on the amount of body fat, but also on its distribution. For example, individuals with increased fat accumulation in the abdominal region have atherogenic lipid profiles and are at increased CV risk. The loss of elasticity in medium and large arteries is an early manifestation of atherosclerosis. The aim of this study was to evaluate whether echocardiographic epicardial adipose tissue, an index of cardiac adiposity, is related to carotid stiffness and carotid intima-media thickness (IMT), indexes of subclinical atherosclerosis, better than waist circumference in hypertensive patients. We studied 459 patients with Grade I and II essential hypertension who were referred to our outpatient clinic over a period from May 2007 to March 2008. The population was first sorted by waist circumference and then by epicardial fat <= 7 or > 7 mm. We measured epicardial fat thickness, waist circumference, carotid artery stiffness, and carotid IMT in all patients. Patients divided according to waist circumference showed no statistical differences in carotid artery stiffness between the two groups. Subjects with epicardial fat > 7 mm were older, had higher systolic, diastolic, and pulse pressure, increased left ventricular mass index, carotid IMT, diastolic parameters, and stiffness parameters compared with those with epicardial fat <= 7 mm (P < 0.001). A positive correlation was found between epicardial fat and age, pulse pressure, stiffness parameters, carotid IMT, systolic blood pressure, and duration of hypertension, and a negative correlation was found with diastolic parameters. Age, carotid IMT, and stiffness parameters were independently related to epicardial fat. Our findings indicate that epicardial fat reflects carotid artery stiffness in hypertension-induced organ damage.