Department of Experimental Medicine, Section of Medical Physiopathology and Endocrinology, Sapienza University of Rome, Rome, Italy.
Int J Cardiol. 2013 Sep 1;167(5):2244-9. doi: 10.1016/j.ijcard.2012.06.011. Epub 2012 Jun 20.
The correlation between obesity and severity of obstructive sleep apnea (OSA) is controversial. Although fat excess is a predisposing factor for the development of OSA, it has not been determined whether fat distribution rather than obesity per se is associated with OSA severity. Epicardial fat thickness (EFT) is an independent index of visceral adiposity and cardiometabolic risk. We investigated the relation between fat distribution and cardiometabolic risk factors, including EFT and common carotid intima-media thickness (cIMT), with the severity of OSA in obese patients.
One hundred and fifteen obese patients (56 males, 59 females) with polysomnographic evidence of OSA (≥ 5 apnea/hypopnea events per hour) of various degrees, without significant differences in grade of obesity as defined by body mass index (BMI), were evaluated. The following parameters were measured: BMI, body composition by dual energy X-ray absorptiometry, EFT, right ventricular end-diastolic diameter (RVEDD) and cIMT by ultrasound, and parameters of metabolic syndrome (waist circumference, arterial blood pressure, fasting glucose, HDL-cholesterol and triglycerides).
EFT, RVEDD, cIMT and trunk/leg fat mass ratio showed a positive correlation with OSA severity in univariate analysis (r=0.536, p<0.001; r=0.480, p<0.001; r=0.345, p<0.001; r=0.330, p<0.001, respectively). However, multiple linear regression analysis showed that EFT was the most significant independent correlate of the severity of OSA (R(2)=0.376, p=0.022).
The present study suggests that, in obese patients, EFT may be included among the clinical parameters associating with OSA severity. The association of EFT with OSA, both cardiovascular risk factors, is independent of obesity as defined by classical measures.
肥胖与阻塞性睡眠呼吸暂停（OSA）严重程度之间的相关性存在争议。虽然脂肪过多是 OSA 发展的一个诱发因素，但尚不确定是脂肪分布而不是肥胖本身与 OSA 严重程度相关。心外膜脂肪厚度（EFT）是内脏肥胖和心血管代谢风险的独立指标。我们研究了脂肪分布与心血管代谢危险因素（包括 EFT 和颈总动脉内膜-中层厚度（cIMT））与肥胖患者 OSA 严重程度之间的关系。
对 115 例肥胖患者（56 名男性，59 名女性）进行了多导睡眠图检查，结果显示 OSA 程度不同（每小时≥5 次呼吸暂停/低通气事件），肥胖程度无明显差异，定义为体重指数（BMI）。测量了以下参数：BMI、双能 X 射线吸收仪测定的身体成分、EFT、右心室舒张末期直径（RVEDD）和超声测量的 cIMT，以及代谢综合征的参数（腰围、血压、空腹血糖、高密度脂蛋白胆固醇和甘油三酯）。
在单因素分析中，EFT、RVEDD、cIMT 和躯干/腿部脂肪质量比与 OSA 严重程度呈正相关（r=0.536，p<0.001；r=0.480，p<0.001；r=0.345，p<0.001；r=0.330，p<0.001）。然而，多元线性回归分析显示，EFT 是 OSA 严重程度的最显著独立相关因素（R(2)=0.376，p=0.022）。
本研究表明，在肥胖患者中，EFT 可能是与 OSA 严重程度相关的临床参数之一。EFT 与 OSA 的关联，这两个都是心血管危险因素，与经典测量定义的肥胖无关。
