State Research Institute Centre for Innovative Medicine.
Vilnius University, Faculty of Medicine, Vilnius, Lithuania.
Blood Press Monit. 2021 Jun 1;26(3):207-214. doi: 10.1097/MBP.0000000000000509.
The purpose of our study was to compare three definitions of ambulatory blood pressure (BP) nocturnal period and to assess their agreement in determining nocturnal BP dipping patterns.
We investigated 69 subjects with metabolic syndrome, aged 50-55 years. In all subjects, we assessed 24-h BP monitoring, electrocardiogram and actigraphy profiles. The nocturnal period was defined in three ways: as a fixed narrow nighttime period from 01:00 to 06:00, as a self-reported sleeping period and as a disappearance and onset of physical activity recorded by the actigraph.
Our study revealed a significant discrepancy between the self-reported and actigraphy-based nocturnal periods (P < 0.001). In addition, different definitions of the nighttime yielded significant differences in determining nondipping, extreme dipping and dipping BP patterns, the identification of the latter being affected the most. The actigraphy-based approach best aligned with the fixed-time determination of the nocturnal period: Cohen's kappa coefficient for the nondipping pattern was 0.78 (0.58-1), for the dipping pattern 0.75 (0.59-0.91) and for the extreme dipping pattern 0.81 (0.65-0.97). In comparison to the self-reported determination of the nocturnal period, using the actigraphy-based approach resulted in reclassifying the nocturnal BP pattern in 20.3% of subjects.
The lack of agreement between fixed-time, self-reported and actigraphy-based determinations of the nighttime period affects the identification of the nocturnal BP patterns. In comparison to the self-reported nocturnal period estimation, the actigraphy-based approach results in the reclassification of BP dipping status in every fifth subject.
本研究的目的是比较三种定义的动态血压（BP）夜间时段，并评估它们在确定夜间 BP 下降模式方面的一致性。
我们调查了 69 名年龄在 50-55 岁之间的代谢综合征患者。在所有患者中，我们评估了 24 小时血压监测、心电图和活动记录仪图谱。夜间时段有三种定义方式：从 01:00 到 06:00 的固定夜间时段，自我报告的睡眠时间，以及由活动记录仪记录的体力活动的消失和开始。
我们的研究显示，自我报告和基于活动记录仪的夜间时段之间存在显著差异（P<0.001）。此外，不同的夜间时段定义在确定非杓型、极度杓型和杓型血压模式方面存在显著差异，其中后者的识别受影响最大。基于活动记录仪的方法与固定时间确定夜间时段最为一致：非杓型模式的 Cohen's kappa 系数为 0.78（0.58-1），杓型模式为 0.75（0.59-0.91），极度杓型模式为 0.81（0.65-0.97）。与自我报告的夜间时段确定相比，使用基于活动记录仪的方法导致 20.3%的患者重新分类夜间血压模式。
固定时间、自我报告和基于活动记录仪的夜间时段确定之间缺乏一致性，影响了夜间 BP 模式的识别。与自我报告的夜间时段估计相比，基于活动记录仪的方法导致每五分之一的患者重新分类 BP 下降状态。
