Bottini P B, Carr A A, Rhoades R B, Prisant L M
Department of Medicine, School of Medicine, Medical College of Georgia, Augusta 30912-3150.
Arch Intern Med. 1992 Jan;152(1):139-44.
Blood pressure is a cardiovascular measurement with dynamic characteristics that can be influenced by a number of internal and external factors. The preferred blood pressure determination method would be one that reduces variability between measurements and that reflects the true blood pressure level. In this article, we present the variability of, and agreement between, the blood pressures collected by two indirect methods on the same patients during a hypertensive research project. Data obtained on patients in a typical clinical setting are also provided. Twenty-four-hour diastolic pressures obtained by the automated method demonstrated no regression to a lower mean, while blood pressures obtained casually in the office exhibited such regression. The 95% confidence interval of repeated measures for casual office blood pressure on a patient in a research setting (35/17 mm Hg) or in typical clinic practice (26/19 mm Hg) were similar, while the range of the mean 24-hour automated blood pressure monitoring (21/11 mm Hg) was smaller and demonstrated less variability. The magnitudes of the differences in blood pressures obtained on separate occasions in the same subjects were significantly lower with automated vs casual blood pressure determination methods (7.9/4.6 vs 13.7/7.4 mm Hg for both systolic and diastolic pressures). The agreement (95% confidence interval) between blood pressures obtained by the two methods (19/12 mm Hg) was found to be similar to the repeatability of automated blood pressure monitoring alone, and superior to that for data recorded casually in the office (35/17 mm Hg). Thus, the variability in mean 24-hour automated blood pressures is less than that for casual office blood pressures. The clinician should understand that the variability of blood pressures measured on an individual may be much greater than that reported for populations of hypertensive patients, and must be considered when applying epidemiologic group data to a specific patient. Moreover, any methodology of indirect blood pressure measurement that may reduce the variability and improve repeatability of casual office blood pressures deserves further consideration.
血压是一种具有动态特征的心血管测量指标，会受到多种内部和外部因素的影响。理想的血压测定方法应能减少测量之间的变异性，并反映真实的血压水平。在本文中，我们展示了在一项高血压研究项目中，两种间接方法在同一患者身上采集的血压的变异性及一致性。同时还提供了在典型临床环境中患者的数据。通过自动方法获得的24小时舒张压未显示出向较低均值的回归，而在办公室随意测量的血压则呈现出这种回归。在研究环境中，对患者随意测量的办公室血压重复测量的95%置信区间（35/17毫米汞柱）与典型临床实践中的（26/19毫米汞柱）相似，而24小时自动血压监测均值的范围（21/11毫米汞柱）更小，变异性也更小。与随意测量血压的方法相比，自动测量血压时，同一受试者在不同时间测得的血压差异幅度显著更低（收缩压和舒张压均为7.9/4.6对13.7/7.4毫米汞柱）。发现两种方法测得的血压之间的一致性（95%置信区间）（19/12毫米汞柱）与仅自动血压监测的可重复性相似，且优于在办公室随意记录的数据（35/17毫米汞柱）。因此，24小时自动血压均值的变异性小于办公室随意测量血压的变异性。临床医生应明白，个体测量的血压变异性可能远大于高血压患者群体报告的变异性，在将流行病学群体数据应用于特定患者时必须予以考虑。此外，任何可能降低变异性并提高办公室随意测量血压可重复性的间接血压测量方法都值得进一步研究。
