Oxford Centre for Clinical Magnetic Resonance Research, Department of Cardiovascular Medicine, University of Oxford, Oxford, UK.
Obesity (Silver Spring). 2010 Dec;18(12):2311-6. doi: 10.1038/oby.2010.64. Epub 2010 Apr 1.
Obesity is an escalating global health problem associated with both an increased risk of death and an increased risk of cardiovascular events. Our goal was to use magnetic resonance imaging (MRI) to determine the effect of obesity and weight loss, in the absence of the traditional cardiovascular risk factors, on aortic pulse wave velocity (PWV) a reliable, reproducible, and accurate clinical measure of aortic stiffness linked to increased mortality. Fifty obese (BMI 38.3 ± 6.8 kg/m(2)) and eighteen normal-weight controls (BMI 22.0 ± 1.7 kg/m(2)) with no identifiable cardiovascular risk factors underwent vascular MRI to assess PWV between the ascending aorta at the level of the pulmonary artery and the abdominal aorta (AA). Twenty-eight subjects underwent repeat imaging after a 1-year period of weight loss. Both groups were well matched for age, systolic blood pressure, fasting glucose, and total cholesterol. Obesity was associated with a 14% increase in PWV (P = 0.021), and with elevated C-reactive protein (CRP) (P < 0.01) and leptin levels (P < 0.001) factors known to cause increase arterial stiffness. Weight loss (average 50% excess weight) was associated with a 14% improvement in PWV (P = 0.03), and with reductions in serum leptin levels (P < 0.01). Obesity, in the absence of the traditional cardiovascular risk factors, is associated with increased aortic PWV, a noninvasive clinical measure of aortic stiffness independently predictive of cardiovascular mortality. Significant weight loss results in improvements in aortic PWV. This may provide a potential link between both obesity and increased mortality, and the reduction in mortality that occurs with weight loss.
肥胖是一个日益严重的全球健康问题，与死亡风险增加和心血管事件风险增加都有关。我们的目的是使用磁共振成像（MRI）来确定肥胖和减肥的影响，在没有传统心血管危险因素的情况下，对主动脉脉搏波速度（PWV）的影响，这是一种可靠、可重复、准确的临床测量方法，与主动脉僵硬有关，与死亡率增加有关。五十名肥胖者（BMI 38.3 ± 6.8 kg/m²）和十八名正常体重对照组（BMI 22.0 ± 1.7 kg/m²），没有可识别的心血管危险因素，接受了血管 MRI 检查，以评估升主动脉在肺动脉水平和腹主动脉（AA）之间的 PWV。28 名受试者在 1 年减肥期后接受了重复成像。两组在年龄、收缩压、空腹血糖和总胆固醇方面都很好地匹配。肥胖与 PWV 增加 14%相关（P = 0.021），与 CRP（P < 0.01）和瘦素水平升高（P < 0.001）相关，这些因素已知会导致动脉僵硬增加。减肥（平均超重 50%）与 PWV 改善 14%相关（P = 0.03），与血清瘦素水平降低相关（P < 0.01）。在没有传统心血管危险因素的情况下，肥胖与增加的主动脉 PWV 相关，这是一种非侵入性的临床测量方法，可独立预测心血管死亡率。显著的体重减轻可改善主动脉 PWV。这可能为肥胖和死亡率增加之间以及减肥带来的死亡率降低之间提供潜在联系。
