Assessment of antihypertensive treatment by ambulatory blood pressure

Advantages of ambulatory blood pressure monitoring. Ambulatory blood pressure monitoring is now used widely to assess the efficacy of antihypertensive drugs in daily life conditions. These 24-h measurements have a number of advantages compared to conventional sphygmomanometric readings. Although a small placebo effect is observed in the first few hours after placebo administration, 24-h average blood pressure is substantially devoid of any placebo effect. Moreover, ambulatory blood pressure is not affected by the alerting reaction usually observed during the doctor's visit. When the 24-h average value is considered, ambulatory blood pressure is more reproducible than clinic blood pressure. Finally ambulatory blood pressure is prognostically more important than clinic blood pressure, since the end-organ damage associated with hypertension is more closely related to 24-h than to clinic blood pressure. Ambulatory blood pressure monitoring is therefore particularly useful when testing the efficacy of new antihypertensive agents on 24-h blood pressure. Testing the combination of verapamil and trandolapril. In a recent study we evaluated the efficacy of a fixed combination of verapamil and trandolapril using both clinic and ambulatory blood pressure measurements. Ambulatory blood pressure monitoring showed that the effect of the combination of verapamil and trandolapril was greater than the effect of either of the two drugs administered alone. However, the clinic blood pressure measurements failed to show any systematically greater effect with the combination versus monotherapy. This further indicates that ambulatory blood pressure is superior to conventional blood pressure in the assessment of antihypertensive drugs.