Differential effects of aliskiren/amlodipine combination and high-dose amlodipine monotherapy on endothelial function in elderly hypertensive patients.

BACKGROUND

The aim of this study was to compare the effects of direct renin inhibitor, aliskiren, and amlodipine combination therapy with those of high-dose amlodipine monotherapy on endothelial function in elderly hypertensive patients.

METHODS

Participants included 105 patients (mean age 77 years) who had receive 5mg amlodipine for 4 weeks. Patients were allocated to the aliskiren/amlodipine group (AL/AM) or the high-dose amlodipine (AM) group. The AL/AM group received 150mg aliskiren in addition to 5mg amlodipine for 8 weeks; then the dose of aliskiren was doubled to 300mg for another 8 weeks. The AM group received 10mg amlodipine for 16 weeks. Of the 105 patients, 87 who underwent measurements of brachial flow-mediated vasodilation (FMD) and nitroglycerin-mediated vasodilation (NMD) before and after the study were included in the analysis.

RESULTS

Blood pressure-lowering effects were similar in the 2 groups. Plasma renin activity significantly decreased in the AL/AM group (P < 0.001) but increased in the AM group (P < 0.001). Improvement of FMD was found in the AL/AM group (2.6% to 3.7%, P = 0.001) but not in the AM group, while NMD did not change in either group. The changes in 24-hour systolic blood pressure (r = -0.60, P < 0.001) and diastolic blood pressure (r = -0.46, P = 0.004) were significantly correlated with improvement of FMD in the AL/AM group but not in the AM group.

CONCLUSION

Addition of aliskiren improved endothelial function in elderly hypertensive patients treated with amlodipine.

CLINICAL TRIAL REGISTRY NUMBER: UMIN000010163.