Chronobiology Laboratory, Department of Physiology, Faculty of Biology, University of Murcia, Spain.
Chronobiol Int. 2012 Jul;29(6):747-56. doi: 10.3109/07420528.2012.679328.
Although the circadian blood pressure (BP) pattern has been extensively studied, the determinants of this rhythm are not fully understood. Peripheral vasodilatation is a regulatory mechanism for BP maintenance. However, it remains to be established whether the increase of nocturnal distal skin temperature associated with heat loss could also reflect the dipping status. For the first time, this paper investigates the relationship between BP and skin wrist temperature (WT), to evaluate whether the WT circadian rhythm can serve as screening procedure to detect dipping/non-dipping BP patterns. In addition, the authors compare the relationship between WT and other variables previously described as determinants of the BP pattern, such as physical activity and body position. Measurements of WT, motor activity, and body position for 5 d, plus ambulatory BP for 24-h during that span, were obtained from 28 diurnally active normotensive volunteers. WT was negatively correlated, whereas activity and body position were positively correlated, with systolic and diastolic BPs. However, these relationships were stronger during the rest than activity phase. In addition, a 78.6% concordance was detected between the observed dips in BP and the predicted BP pattern calculated based on the WT rhythm. Thus, these results suggest that the increase in WT produced by heat loss during the rest phase through peripheral skin blood vessels is the result of blood vessel vasodilatation reflexes in response to a shift from a standing to a supine position, together with shift in the circadian sympathetic/parasympathetic balance (nocturnal parasympathetic activation). In conclusion, WT could be considered as a potential new screening procedure to implement the diagnosis of non-dipping BP pattern.
尽管已经广泛研究了昼夜血压（BP）模式，但这种节律的决定因素尚未完全了解。外周血管舒张是维持血压的调节机制。然而，与热量损失相关的夜间远端皮肤温度增加是否也能反映出下倾状态，仍有待确定。本文首次研究了 BP 与手腕皮肤温度（WT）之间的关系，以评估 WT 昼夜节律是否可以作为检测下倾/不下倾 BP 模式的筛选程序。此外，作者比较了 WT 与其他先前描述的 BP 模式决定因素之间的关系，例如体力活动和身体姿势。在 5 天内测量 WT、运动活动和身体姿势，以及在此期间的 24 小时动态血压，共有 28 名日间活跃的正常血压志愿者参与。WT 与收缩压和舒张压呈负相关，而活动和身体姿势与收缩压和舒张压呈正相关。然而，这些关系在休息期比活动期更强。此外，在观察到的 BP 下倾与根据 WT 节律计算的预测 BP 模式之间，检测到了 78.6%的一致性。因此，这些结果表明，在休息期间通过外周皮肤血管产生的 WT 增加是血管舒张反射的结果，这种反射是由于从站立到仰卧姿势的转变，以及昼夜交感神经/副交感神经平衡的转变（夜间副交感神经激活）。总之，WT 可以被认为是一种潜在的新的筛选程序，用于实施非下倾 BP 模式的诊断。
