Hypertension：降压治疗对24h肱动脉压和中心动脉压昼夜节律的影响

临床上传统的血压测量多采用肱动脉血压。目前对无创测量中心动脉压的关注度也在不断增加，原因是中心动脉压更准确反映靶器官的灌注压力，有研究显示与肱动脉压相比，中心动脉压可更好的预测靶器官损害和临床预后。
人的血压存在一个自然的昼夜节律，表现为晚上血压下降，在睡醒之前血压急剧增高。昼夜节律紊乱如孤立的夜间血压升高或者夜间血压下降减小，清晨血压升高加大，导致心血管疾病风险增加。目前没有关于中心动脉压昼夜变化情况以及中心动脉压与肱动脉压昼夜变化的时间关系的研究。英国伦敦的William等研究人员通过ASSERTIVE研究（AliSkiren Study of profound antihypERtensive efficacy in hyperTensIVEpatients）的一个亚组研究，即AmCAP 研究（Ambulatory Brachial and Central AorticPressure measurement ）对受试者同时进行昼夜24h肱动脉压和中心动脉压测量并行分析。
研究共有171例受试对象。研究人员通过一个安装在类似手表的装置带子上的血压计测量受试者的24h肱动脉血压和中心动脉压。所有受试者被随机分配至阿利吉仑 300mg qd或替米沙坦 80mg qd两组中接受降压治疗12周。分别记录基线和研究结束时的门诊肱动脉压和中心动脉压。
研究发现肱动脉压和中心动脉压均表现出典型的昼夜模式，其中夜间血压较低。但是与肱动脉压比较，中心动脉压夜间降低较少，脉压放大减小（均P<0.0001 ）。
这些效应不受血压降低影响，在经日间夜间血压和心率校正后依然存在这种趋势（P=0.02）。
该研究显示肱动脉压和中心动脉压有不同的昼夜节律，且不受降压治疗影响，其中夜间的中心动脉压相对较高。这一数据显示夜间中心动脉压或对预后有重要作用，应进一步观察研究。

与降压治疗相关的拓展阅读：

• Lancet：不同体重人群的利尿剂降压治疗存在差异
• Neurology：卒中后降压治疗依从性高低决定心血管事件风险
• ASBMR年会：老年人降压治疗时骨折风险高
• [ESH2012]尽早降压治疗可预防心血管事件
• [ESH2012]降压治疗急需解决的几个问题 更多信息请点击：有关降压治疗更多资讯

Novel Description of the 24-Hour Circadian Rhythms of Brachial Versus Central Aortic Blood Pressure and the Impact of Blood Pressure Treatment in a Randomized Controlled Clinical Trial: The Ambulatory Central Aortic Pressure (AmCAP) Study.
Abstract
Elevated brachial blood pressure (BP) is associated with increased cardiovascular risk and predicts morbidity and mortality in humans. Recently, 24-hour ambulatory BP monitoring and assessment of central aortic BP have been introduced to improve BP phenotyping. The Ambulatory Central Aortic Pressure (AmCAP) study combines these approaches and describes, for the first time, the diurnal patterns of simultaneously measured 24-hour ambulatory brachial and central pressures in a prespecified substudy embedded within a clinical trial of BP lowering in patients with hypertension. Twenty-four-hour ambulatory brachial and central pressure measurements were acquired using a tonometer mounted into the articulating strap of a wristwatch-like device (BPro) in 171 participants with hypertension recruited into the ASSERTIVE (AliSkiren Study of profound antihypERtensive efficacy in hyperTensIVE patients) trial. Participants were randomly assigned to BP lowering with either aliskiren 300 mg QD or telmisartan 80 mg QD for 12 weeks. Ambulatory brachial and central BP was measured in all participants both at baseline and at study end. Brachial and central BP both demonstrated typical diurnal patterns with lower pressures at night. However, night time was associated with smaller reductions in central relative to brachial pressure and decreased pulse pressure amplification (P<0.0001 for both). These effects were not modulated after BP lowering and were maintained after adjustment for day and night-time BP and heart rate (P=0.02). This study demonstrates that brachial and central pressure show different diurnal patterns, which are not modulated by BP-lowering therapy, with relatively higher night-time central pressures. These novel data indicate that night-time central BP may provide prognostic importance and warrants further investigation.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00865020.