• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Emerging themes in epidemiology >Exploring diurnal variation using piecewise linear splines: an example using blood pressure
【24h】

Exploring diurnal variation using piecewise linear splines: an example using blood pressure

机译：使用分段线性样条曲线研究昼夜变化：以血压为例

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

BackgroundThere are many examples of physiological processes that follow a circadian cycle and researchers are interested in alternative methods to illustrate and quantify this diurnal variation. Circadian blood pressure (BP) deserves additional attention given uncertainty relating to the prognostic significance of BP variability in relation to cardiovascular disease. However, the majority of studies exploring variability in ambulatory blood pressure monitoring (ABPM) collapse the data into single readings ignoring the temporal nature of the data. Advanced statistical techniques are required to explore complete variation over 24?h. MethodsWe use piecewise linear splines in a mixed-effects model with a constraint to ensure periodicity as a novel application for modelling daily blood pressure. Data from the Mitchelstown Study, a cross-sectional study of Irish adults aged 47–73?years (n?=?2047) was utilized. A subsample (1207) underwent 24-h ABPM. We compared patterns between those with and without evidence of subclinical target organ damage (microalbuminuria). ResultsWe were able to quantify the steepest rise and fall in SBP, which occurred just after waking (2.23?mmHg/30?min) and immediately after falling asleep (?1.93?mmHg/30?min) respectively. The variation about an individual’s trajectory over 24?h was 12.3?mmHg (standard deviation). On average those with microalbuminuria were found to have significantly higher SBP (7.6?mmHg, 95% CI 5.0–10.1) after adjustment for age, sex and BMI. Including an interaction term between each linear spline and microalbuminuria did not improve model fit. ConclusionWe have introduced a practical method for the analysis of ABPM where we can determine the rate of increase or decrease for different periods of the day. This may be particularly useful in examining chronotherapy effects of antihypertensive medication. It offers new measures of short-term BP variability as we can quantify the variation about an individual’s trajectory but also allows examination of the variation in slopes between individuals (random-effects).
机译：背景技术有许多生理节律遵循昼夜节律的例子，研究人员对替代方法来说明和量化这种昼夜变化感兴趣。鉴于与心血管疾病相关的BP变异性对预后意义的不确定性，昼夜血压（BP）值得更多关注。但是，大多数研究动态血压监测（ABPM）变异性的研究都将数据折叠成单个读数，而忽略了数据的时间特性。需要先进的统计技术来探索24小时内的完整变化。方法我们在具有约束条件的混合效应模型中使用分段线性样条，以确保周期性，这是建模日常血压的一种新颖应用。利用来自Mitchelstown研究的数据，该研究是对47-73岁（n = 2047）的爱尔兰成年人进行的横断面研究。子样本（1207）经过24小时ABPM。我们比较了有和没有亚临床靶器官损害（微量蛋白尿）证据的人之间的模式。结果我们能够量化出分别在醒来之后（2.23？mmHg / 30？min）和入睡后立即出现的（1.93？mmHg / 30？min）SBP的最大上升和下降。一个人在24？h内的轨迹变化为12.3？mmHg（标准偏差）。调整了年龄，性别和BMI后，平均有微量白蛋白尿者的SBP（7.6？mmHg，95％CI 5.0-10.1）显着升高。包括每个线性样条和微量白蛋白尿之间的相互作用项不能改善模型拟合。结论我们介绍了一种分析ABPM的实用方法，可以确定一天中不同时期的增加或减少速率。这对于检查降压药物的计时疗法效果可能特别有用。它提供了短期BP变异性的新度量，因为我们可以量化个人轨迹的变化，但也可以检查个人之间的斜率变化（随机效应）。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号