Kario K, Shimada K
Department of Cardiology, Jichi Medical School, Tochigi, Japan.
Am J Hypertens. 1997 Mar;10(3):261-8. doi: 10.1016/s0895-7061(96)00409-8.
Previous studies have discovered that amlodipine given once daily can reduce blood pressure (BP) throughout the day and night. The effects of amlodipine on day and night BP have not been fully investigated in groups of hypertensives with different diurnal variations. In a prospective study, we performed 24-h ambulatory BP monitoring before and after once-daily use of amlodipine in three groups of asymptomatic elderly hypertensive patients with different nocturnal BP reductions, as follows: 10 extreme dippers with nocturnal reduction of systolic BP > or = 20% of daytime systolic BP, 17 dippers (reduction by > or = 10% to < 20%), and 23 nondippers (reduction by < 10%). At baseline, the office and the awake BP were similar in all three groups, whereas the nighttime BP was significantly higher in the nondippers than in the dippers and in the dippers than in the extreme dippers. After treatment, the office and the daytime BP were both equally reduced in all three groups. On the other hand, the nighttime BP was significantly reduced both in the nondippers and, to a lesser extent, in the dippers. In the extreme dippers, however, no further reductions of nocturnal BP were found. Significant positive correlations were found between baseline BP levels and the BP reduction after amlodipine therapy was begun. No BP reduction > 10 mm Hg was observed when the baseline systolic/diastolic BP was < 120/70 mm Hg. Multiple linear regression analysis disclosed that the nighttime BP reduction afforded by amlodipine was dependent on the baseline nighttime BP levels, but not on the baseline nocturnal fall of BP. Once-daily use of amlodipine reduced BP levels throughout the day and night in hypertensive patients who show minimal or mild nocturnal BP fall, but it had no effects on nocturnal BP in those who show a substantial nighttime BP reduction. Thus, when we controlled using daytime office BP, amlodipine might not further reduce nocturnal BP to the extent that it accelerates the brain ischemia in some hypertensive patients with marked nocturnal BP reduction.
既往研究发现，每日服用一次氨氯地平可全天降低血压（BP）。在不同昼夜血压变化的高血压患者群体中，氨氯地平对昼夜血压的影响尚未得到充分研究。在一项前瞻性研究中，我们对三组夜间血压下降情况不同的无症状老年高血压患者，在每日服用一次氨氯地平前后进行了24小时动态血压监测，具体如下：10例极端杓型血压者，夜间收缩压下降幅度≥日间收缩压的20%；17例杓型血压者（下降幅度≥10%至＜20%）；23例非杓型血压者（下降幅度＜10%）。在基线时，三组患者的诊室血压和清醒时血压相似，而夜间血压在非杓型血压者中显著高于杓型血压者，在杓型血压者中显著高于极端杓型血压者。治疗后，三组患者的诊室血压和日间血压均同等程度降低。另一方面，非杓型血压者的夜间血压显著降低，杓型血压者的夜间血压也有一定程度降低，但降低幅度较小。然而，在极端杓型血压者中，未发现夜间血压进一步降低。在开始氨氯地平治疗后，基线血压水平与血压降低之间存在显著正相关。当基线收缩压/舒张压＜120/70 mmHg时，未观察到血压降低幅度＞10 mmHg。多元线性回归分析显示，氨氯地平引起的夜间血压降低取决于基线夜间血压水平，而非基线夜间血压下降幅度。每日服用一次氨氯地平可降低夜间血压下降幅度最小或轻度下降的高血压患者的全天血压水平，但对夜间血压显著下降的患者的夜间血压无影响。因此，当我们以日间诊室血压作为对照时，氨氯地平可能无法进一步降低夜间血压，以至于在一些夜间血压显著降低的高血压患者中加速脑缺血。
