Feasibility of 24-h central blood pressure monitoring: experience from multinational clinical trial assessing the efficacy of perindopril/indapamide/amlodipine.

OBJECTIVES: Brachial blood pressure (BP) is a predictor of cardiovascular events. Evidence suggests that central BP (CBP) provides additional information for cardiovascular risk assessment. Methods to assess 24-h CBP are now available. Our objective was to assess the feasibility of 24-h CBP monitoring in clinical trials and its ability for drug evaluation. METHODS: Data are issued from an international phase 3 randomized clinical trial comparing the efficacy of perindopril/indapamide/amlodipine vs. perindopril/indapamide (Per/Ind), in uncontrolled hypertensive patients treated with Per/Ind. 24-h ambulatory BP monitoring (ABPM) was performed at baseline and after 1-month treatment using the Mobil-O-Graph device which provide brachial BP and CBP and arterial parameters. RESULTS: From the 345 patients included in the ABPM substudy, 276 had two valid ABPM (M0 and M1) for brachial BP assessment (80%). After applying device/software built-in and expert quality control criteria on these recordings, 210 (76%) had valid data at M0 and M1 for the assessment of CBP. After 1 month, superior ambulatory central SBP reductions were observed in the perindopril/indapamide/amlodipine (n = 101) vs. Per/Ind group (n = 109) for 24-h/daytime/night-time periods (-4.5 mmHg, P = 0.002/-5.0, P < 0001/-4.1 mmHg, P = 0.016, respectively). Similar trends were observed for pulse wave velocity and other central parameters. CONCLUSION: Recording 24-h central ABPM and its derived arterial parameters needs a strict expert quality control and must consider a loss of up to 39% of the population included in the ABPM substudy. This method can be used to assess drug effect.