Eguchi Kazuo, Hoshide Satoshi, Miyashita Hiroshi, Nagasaka Shoichiro, Kario Kazuomi
Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University, Shimotsuke, Japan.
Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University, Shimotsuke, Japan.
Atherosclerosis. 2016 Mar;246:338-43. doi: 10.1016/j.atherosclerosis.2016.01.034. Epub 2016 Jan 26.
Radial augmentation index (rAI), a marker of aortic wave reflection, is usually lower in patients with diabetes (DM) than in non-DM subjects, even though atherosclerotic change is advanced in DM.
We sought to explore why rAI in DM is lower than in non-DM.
We performed radial applanation tonometry in 1787 subjects who had at least one cardiovascular risk factor. The rAI was defined as [late systolic shoulder pressure amplitude (PP2)]/[radial pulse pressure (rPP)]. The late systolic shoulder blood pressure (SBP2) and PP2 of a radial pressure wave were used as estimates of the central SBP and PP (cPP), respectively.
The age (65.8 ± 9.8 vs. 65.8 ± 12.1 yrs) and mean brachial SBP (141 ± 16 vs. 141 ± 17 mmHg) were similar between the DM and non-DM groups. The rAI was significantly lower in the DM group (83.3 ± 14.1 vs. 87.3 ± 15.7%, p < 0.001), but clinic PP (62 ± 14 vs. 59 ± 14 mmHg, p < 0.001) and cPP (51 ± 15 vs. 49 ± 15 mmHg, p = 0.019) were significantly greater in the DM group than in the non-DM group. In multivariable analyses adjusting for covariates, the significant determinants of rAI were the estimated glomerular filtration rate (eGFR) (β = 0.17, p < 0.001) in the DM group, and the log-transformed homeostatic model assessment of insulin resistance (HOMA-IR) (β = -0.15, p < 0.001) in the non-DM group. The same trends were also seen for central SBP and cPP.
The lower rAI in DM associated with higher cPP compared to non-DM suggests proximal conduit-predominant arterial stiffening causing reduced reflection coefficients at systemic reflection sites. As renal function decreases, a cPP increase may overcome the increase of augmentation pressure in the DM group.
作为主动脉波反射标志物的桡动脉增强指数（rAI），在糖尿病（DM）患者中通常低于非糖尿病受试者，尽管DM患者的动脉粥样硬化改变更为严重。
我们试图探究为何DM患者的rAI低于非糖尿病患者。
我们对1787名至少有一项心血管危险因素的受试者进行了桡动脉压平式眼压测量。rAI定义为[收缩晚期肩峰压幅度（PP2）]/[桡动脉脉压（rPP）]。桡动脉压力波的收缩晚期肩峰血压（SBP2）和PP2分别用作中心收缩压（cSBP）和中心脉压（cPP）的估计值。
DM组和非DM组的年龄（65.8±9.8岁对65.8±12.1岁）和平均肱动脉收缩压（141±16mmHg对141±17mmHg）相似。DM组的rAI显著更低（83.3±14.1%对87.3±15.7%，p<0.001），但DM组的临床脉压（62±14mmHg对59±14mmHg，p<0.001）和cPP（51±15mmHg对49±15mmHg，p=0.019）显著高于非DM组。在对协变量进行校正的多变量分析中，DM组中rAI的显著决定因素是估计的肾小球滤过率（eGFR）（β=0.17，p<0.001），非DM组中是胰岛素抵抗稳态模型评估的对数转换值（HOMA-IR）（β=-0.15，p<0.001）。中心收缩压和cPP也呈现相同趋势。
与非DM患者相比，DM患者中较低的rAI与较高的cPP相关，提示近端管道为主的动脉僵硬度增加导致全身反射部位的反射系数降低。随着肾功能下降，cPP升高可能会抵消DM组中增强压的升高。
