Underestimation of 24-hour hypotensive efficacy of nifedipine GITS versus enalapril: ambulatory recording as an adjunct to clinical blood pressure measurement.

摘要

AIMS: Short-acting calcium entry blockers should be used primarily in slow-release form. Furthermore, studies of the antihypertensive efficacy of drugs can be negatively influenced by between 15% and 30% of the enrolled patients not being hypertensive according to ambulatory blood pressure (BP) measurement. Thus, a randomized double-blind multicenter parallel-group study was conducted to compare the effect of nifedipine GITS (gastrointestinal therapeutic system) with enalapril. METHODS AND RESULTS: After a 2-week placebo run-in period, 186 patients with a sitting diastolic BP > or = 95 mmHg were enrolled for an 8-week treatment period. They received 30-60 mg nifedipine GITS or 5-10 mg enalapril. Diastolic BP fell comparably from 99 to 87 mmHg (p < 0.01) in the nifedipine GITS group, and from 100 to 88 mmHg (p < 0.01) in the enalapril group. The increase in BP 2 h before waking, however, was suppressed significantly more by nifedipine. Furthermore, this study highlighted the existence of "whitecoat" hypertension in a number of patients, especially when clinical BP was used to identify hypertension. Of the patients who had been identified as hypertensive before randomization by standardized BP measurement, 53 (28.5%) were identified as non-hypertensives by 24-h BP monitoring. This led to an underestimation of the efficacy of the antihypertensive therapy. CONCLUSION: Nifedipine GITS as well as enalapril are comparably effective antihypertensive drugs.