Time-weighted vs. conventional quantification of 24-h average systolic and diastolic ambulatory blood pressures
Time-weighted vs. conventional quantification of 24-h average systolic and diastolic ambulatory blood pressures
复制标题
DOI：
10.1097/hjh.0b013e328334f220
复制
发表时间：
2010-03-01
影响因子：
4.9
通讯作者：
Parati, Gianfranco
中科院分区：
文献类型：
--
作者：
Octavio, Jose A.;Contreras, Jesus;Parati, Gianfranco
背景 基于所有血压读数的平均值计算平均 24 小时动态血压 (BP)、SBP 和 DBP 的传统方法忽略了白天测量次数通常多于夜间的事实，这种不平衡可能导致高估 24 小时平均血压。我们研究的目的是量化这种可能的偏差并探索其决定因素。方法将 450 名未经治疗的个体分为三组（每组 150 人），采用三种不同的日间/夜间动态血压测量计划：I 组，每小时 4 次（白天）/2 次（夜间）读数；I 组，每小时 4 次（白天）/2 次（夜间）读数；第二组，每小时四次（白天）/三次（夜间）读数；第三组，24 小时内每 30 分钟测量一次血压读数。计算每小时和 24 小时平均值。将所有 SBP 和 DBP 值的常规 24 小时平均值与每小时 SBP 和 DBP 平均值的平均值进行比较（时间加权量化）。计算各组24小时常规血压与24小时时间加权血压的差异，并与夜间血压下降程度和昼夜读数次数比值相关。 结果 三组中24小时常规血压与24小时时间加权血压高度相关（r > 0.99），24小时常规收缩压和舒张压显着高于对照组（P < 0.01）。 I 组和 II 组中对应的 24 小时时间加权值，但 III 组中没有（Bland-Altman 分析）。在第 I 组和第 II 组中，偏差大小与读数次数的日/夜比以及夜间血压下降有关（P < 0.01），但在第 III 组中则不然。 结论 白天每小时读数次数较多，导致传统 24 小时平均血压高估，特别是对于保留夜间血压下降的个体。这可以通过在 24 小时内安排相同数量的每小时读数或通过执行 24 小时血压的时间加权量化来避免。这些不同方法的临床意义值得进一步研究。 J Hypertens 28:459-464 (c) 2010 Wolters Kluwer Health 垂直杆 Lippincott Williams & Wilkins。
Background Conventional calculation of mean 24-h ambulatory blood pressure (BP), SBP and DBP based on the average of all BP readings disregards the fact that a larger number of measurements is usually scheduled during the daytime than at night, an imbalance possibly leading to an overestimation of 24-h average BP. The aim of our study was to quantify this possible bias and to explore its determinants.Methods Four hundred and fifty untreated individuals were subdivided into three groups (150 individuals each) with three different ambulatory blood pressure measurement schedules for day/night: group I, four (day)/two (night) readings/h; group II, four (day)/three (night) readings/h; and group III, with BP readings every 30 min throughout 24 h. Hourly and 24-h averages were computed. The conventional 24-h averages of all SBP and DBP values were compared with the averages of hourly SBP and DBP mean values (time-weighted quantification). The difference between 24-h conventional and 24-h time-weighted BP was computed in each group and related to the degree of nocturnal BP dip and to the ratio between the number of readings of day and night.Result In the three groups, 24-h conventional and 24-h time-weighted BP values were highly correlated (r > 0.99), 24-h conventional SBP and DBP being significantly higher (P < 0.01) than the corresponding 24-h time-weighted values in groups I and II but not in group III (Bland-Altman analysis). The bias magnitude was related to the day/night ratio in number of readings and to nocturnal BP dip in groups I and II (P < 0.01) but not in group III.Conclusion The higher number of readings/h during daytime leads to an overestimation of conventional 24-h average BP, particularly in individuals with preserved nocturnal BP dipping. This can be avoided either by scheduling the same number of readings/h throughout 24 h or by performing a time-weighted quantification of 24-h BP. The clinical implications of these different approaches deserve further investigation. J Hypertens 28:459-464 (c) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.