The Irish Longitudinal Study on Ageing, Trinity College Dublin, University of Dublin, Ireland.
Trinity Centre for Biomedical Engineering, Trinity College Dublin, University of Dublin, Ireland.
J Gerontol A Biol Sci Med Sci. 2021 Apr 30;76(5):885-892. doi: 10.1093/gerona/glaa315.
Orthostasis is a potent physiological stressor which adapts with age. The age-related accumulation of health deficits in multiple physiological systems may impair the physiological response to orthostasis and lead to negative health outcomes such as falls, depression, and cognitive decline. Research to date has focused on changes with orthostasis at prespecified intervals of time, without consideration for whole signal approaches.
One-dimensional statistical parametric mapping identified regions in time of significant association between variables of interest using a general linear model. Frailty index operationalized accumulated health and social deficits using 32-items from a computer-assisted interview. This study examined the association of frailty index on blood pressure, heart rate, and cerebral oxygenation during an orthostatic test in a sample of 2742 adults aged 50 or older from The Irish Longitudinal Study on Ageing.
Frailty index was seen to be negatively associated with cerebral oxygenation changes from baseline over a period of 7 seconds (p = .036). Heart rate and systolic blood pressure were positively and negatively associated with frailty index over periods of 17 seconds (p = .001) and 10 seconds (p = .015), respectively.
Statistical parametric mapping demonstrated these significant regions of cerebral oxygenation during orthostasis provide indirect evidence of impaired autoregulation associated with frailty. Statistical parametric mapping also replicated prior relationships in heart rate and systolic blood pressure associated with a higher frailty index. These findings highlight the utility of 1-dimensional statistical parametric modeling in identifying significant regions of interest in physiological recordings.
直立位是一种强大的生理应激源，会随年龄而适应。多个生理系统中与年龄相关的健康缺陷积累可能会损害对直立位的生理反应，并导致负面健康后果，如跌倒、抑郁和认知能力下降。迄今为止的研究主要集中在特定时间间隔内与直立位相关的变化，而没有考虑整个信号方法。
一维统计参数映射使用广义线性模型确定变量之间有显著关联的时间区域。衰弱指数使用计算机辅助访谈中的 32 个项目来操作累计健康和社会缺陷。本研究在 2742 名年龄在 50 岁或以上的爱尔兰老龄化纵向研究参与者的直立测试中，检查了衰弱指数与血压、心率和脑氧合之间的关联。
衰弱指数与 7 秒内（p =.036）从基线开始的脑氧合变化呈负相关。心率和收缩压与衰弱指数在 17 秒（p =.001）和 10 秒（p =.015）期间呈正相关和负相关。
统计参数映射表明，直立位期间这些显著的脑氧合区域提供了与衰弱相关的自主调节受损的间接证据。统计参数映射还复制了心率和收缩压与较高衰弱指数相关的先前关系。这些发现突出了一维统计参数建模在识别生理记录中显著感兴趣区域的有用性。
