A Randomized Crossover Study of the Additive Effect of Lercanidipine and Indapamide in Patients with the Mild to Moderate Hypertension

Background and Objectives：There is evidence available from randomized control trials about the additive effects of combination regimens that are mainly based on diuretics and β-blockers or ACE inhibitors. Yet there are some arguments about the effect of the combination of calcium channel blockers (CCBs) and diuretics. We aimed to study the blood pressure-lowering effects of lercanidipine, indapamide or a combination therapy on the home blood pressure (HBP) and the 24-hour ambulatory blood pressure (ABP), and we wanted to examine the agreement with using these two methods. Subjects and Methods：70 patients participated in this randomized open crossover design study. The treatments in each phase were 10 mg lercanidipine (L) and 1 mg indapamide (I), separately and also in combination (L+I). Each patient had their HBP checked twice during each phase and the 24h ABP was checked in two of the 3 phases. We also measured the agreement between the HBP and ABP by using a Bland-Altman plot. Results：58 patients (mean age: 49±9 (31-71) years; 37 males and 21 females) completed the study. The blood pressure was significantly reduced during all the active treatments compared with the baseline (L: 160.2±12/100.3±9 mmHg, I; 130.5±9.3/86.0±8.1 mmHg, 129.2±12.9/83.9±11.1 mmHg, L+I:124.9±10.9/81.3±8.5 mmHg, p<.000) and the BP for the combination therapy was also signifi-cantly less than those BPs for both the other monotherapies (L+I vs. L: p<.002, L+I vs. I: p<.01) by measurin