[Effects of nitrendipine on circadian variation of blood pressure in inpatients with renal parenchymal hypertension: assessment by ambulatory blood pressure monitoring].

Objective: To study the effect of once-daily administration of a nitrendipine tablet 10 mg on 24-hour ambulatory blood pressure in inpatients with renal parenchymal hypertension.

Methods: Sixteen patients participated in the present study, and one patient was withdrawn because the baseline office blood pressure was less than 140/90 mmHg. In the baseline period, ambulatory blood pressure was monitored every 30 minutes for 30 hours. After the baseline measurement, nitrendipine 10 mg was orally administered once daily every morning for 7 days. The 30-hour ambulatory blood pressure monitoring was repeated after Day 6.

Results: Fifteen patients (aged 64.9 +/- 15.0 years) completed the study protocol. Baseline office blood pressure was 157.9 +/- 17.5/84.7 +/- 12.5 mmHg (mean +/- SD). Nitrendipine 10 mg tablets significantly reduced both systolic blood pressure (SBP) and diastolic blood pressure (DBP) at least for 11 hours after administration compared with those at baseline. The rate of "Decrease" (reduction in blood pressure > or = 20/10 mmHg and/or achieved blood pressure < 140/90 mmHg at trough point) was 60.0% (9/15). Eleven patients were considered as effective cases at peak point (maximal reduction in blood pressure > or = 20/10 mmHg). The rate of "Decrease" in effective cases at peak point was 72.7% (8/11).

Conclusion: These results suggest that a once-daily administration of nitrendipine 10 mg tablets is effective for the 24-hour control of blood pressure in patients with renal parenchymal hypertension.