Mancia G, Salvetti A
Cattedra di Medicina Interna, Ospedale S. Gerardo, Monza, Università di Milano.
G Ital Cardiol. 1994 Aug;24(8):1043-8.
The trough-to-peak ratio (T/P) is more and more frequently employed to assess in a simple fashion the duration and the homogeneity of the antihypertensive effect of a drug over a between-dose interval. This paper emphasizes that to provide reliable data T/P should be calculated only when there is a clearcut antihypertensive effect and that other important features are its within-individual reproducibility and an acceptable value (> 50%) in most individual patients. T/P can be assessed by sphygmomanometric measurements obtained at the end of the between-dose interval and at or near the maximal effect of the drug within the dose interval. It is more and more common, however, to assess T/P by ambulatory blood pressure monitoring which, although characterized by a number of limitations (e.g. low reproducibility of blood pressure values within the 24 hours), allows to avoid a parallel placebo group and to simplify the study design. While a high T/P suggests that the dose and the between-dose interval of a drug is capable to provide an adequate therapeutic coverage a low T/P indicates that the therapeutic coverage is insufficient. The posology must then be changed (more frequent and/or greater doses) to avoid an insufficient protection against hypertension.
谷峰比值（T/P）越来越频繁地被用于以一种简单的方式评估药物在给药间隔期内降压效果的持续时间和一致性。本文强调，为了提供可靠的数据，只有在有明确的降压效果时才应计算T/P，并且其他重要特征包括其个体内的可重复性以及在大多数个体患者中可接受的值（>50%）。T/P可以通过在给药间隔期末以及在给药间隔期内药物达到最大效果时或接近最大效果时获得的血压测量值来评估。然而，通过动态血压监测来评估T/P越来越普遍，动态血压监测虽然存在一些局限性（例如24小时内血压值的低可重复性），但可以避免设置平行安慰剂组并简化研究设计。高T/P表明药物的剂量和给药间隔能够提供足够的治疗覆盖，而低T/P则表明治疗覆盖不足。然后必须改变给药方案（更频繁和/或更大剂量）以避免对高血压的保护不足。
