Elliott H L
Department of Medicine and Therapeutics, Western Infirmary, Glasgow, UK.
J Hypertens Suppl. 1994 Jul;12(5):S29-33.
DEFINITION OF TROUGH: PEAK RATIO: Applied to an antihypertensive drug, the term trough: peak ratio provides an index of how well the antihypertensive effect is sustained over the dose interval. This ratio is usually expressed as a percentage and is determined from the ratio of the blood pressure reduction at trough, i.e. at the end of the dose interval and before the next dose is administered, relative to the blood pressure reduction at the time of the peak drug effect. According to guidelines issued by the United States Food and Drug Administration, 50% is the minimum requirement for an acceptable trough: peak ratio.
Unfortunately, the Food and Drug Administration has not produced guidelines describing the methodology, required to define the trough: peak ratio, apart from the requirement that account be taken of placebo effects. However, although the timing of the trough measurement is defined, the response to an antihypertensive drug is influenced by intra- and interindividual variability, and to measure the peak response it is necessary to take multiple blood pressure measurements throughout the dose interval. This will take account not only of diurnal variations in an individual subject's blood pressure but also of interindividual variability in the timing and magnitude of the peak response to treatment.
Assuming it is appropriately measured, the trough: peak ratio is a useful index of the consistency of the antihypertensive response throughout the dose interval and of the optimal dose frequency.
谷值：峰值比的定义：应用于抗高血压药物时，谷值：峰值比这一术语提供了一个指标，用于衡量在给药间隔期间抗高血压效果的维持程度。该比值通常以百分比表示，由谷值时（即给药间隔结束且下次给药前）的血压降低值与药物效应峰值时的血压降低值之比确定。根据美国食品药品监督管理局发布的指南，可接受的谷值：峰值比的最低要求为50%。
遗憾的是，除了要求考虑安慰剂效应外，食品药品监督管理局尚未制定描述定义谷值：峰值比所需方法的指南。然而，尽管谷值测量的时间已确定，但抗高血压药物的反应受个体内和个体间变异性的影响，为了测量峰值反应，有必要在整个给药间隔内多次测量血压。这不仅会考虑个体受试者血压的昼夜变化，还会考虑个体间对治疗峰值反应的时间和幅度的变异性。
假设测量方法得当，谷值：峰值比是衡量整个给药间隔内抗高血压反应一致性以及最佳给药频率的有用指标。
