[Circadian pressure variability and pressure peaks during treatment of mild to moderate essential hypertension with felodipine].

It is not yet known how blood pressure variability contributes to the vascular changes associated with hypertension, but 2 possibly relevant factors are mean blood pressure levels over time and pressure peaks. It has been observed that patients in whom the variability in 24-hour blood pressure is low have a lower prevalence and severity of target organ damage. We carried out a whole-day continuous intraarterial blood pressure recording (Oxford method) in 12 essential hypertensive patients after a 2-week placebo period and after a 4-week felodipine treatment, administered in an extended release formulation, 10 mg once daily at 7 am. Felodipine significantly lowered systolic and diastolic blood pressure values throughout the 24 hours (p less than 0.005 to 0.001). Also, hourly variabilities of systolic and diastolic blood pressure during whole-day monitoring were significantly reduced (p less than 0.05 to 0.001), evaluated on the basis of the hourly means of standard deviation of systolic and diastolic blood pressure. In addition, felodipine significantly lowered the values of blood pressure reached during both dynamic exercise (bicycle ergometer, p less than 0.001) and isometric exercise (handgrip, p less than 0.001).