Abstract
Background: Combination antihypertensive therapy with an angiotensin receptor blocker (ARB) and a calcium channel blocker (CCB) or diuretics is common. This subanalysis investigated blood pressure (BP) variability in patients receiving ARB-based combination therapy. Methods: In a prospective, randomized, open-label trial, hypertensive outpatients (≥65 years) who did not achieve their target BP with ARB monotherapy switched to losartan 50 mg/hydrochlorothiazide 12.5 mg (ARB + D) or ARB plus amlodipine 5 mg (ARB + C) for 12 months. Clinic BP and heart rate (HR), measured every 3 months, visit-to-visit variability and seasonal variation were evaluated. Results: No significant between-group differences in average, maximum, or minimum systolic or diastolic BP, or HR, were found. Visit-to-visit BP variability (systolic) was significantly higher in the ARB + D group than in the ARB + C group. When each group was subdivided into two seasonal groups (summer and winter), no significant between-group differences in BP were found. Multivariate regression analyses showed a tendency toward negative correlation between outdoor temperature and urinary albumin:creatinine ratio and estimated glomerular filtration rate at 12 months in the ARB + D group. Conclusion: Combination therapy with an ARB plus a CCB may be preferable to that with an ARB plus diuretics for decreasing BP variability. As for seasonal variability, both treatments can be used safely regardless of season.
Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. The CAMUI Trial was funded by the Waksman Foundation of Japan Inc.
Supplementary material available online
Supplementary Tables 1–3
Notes
* The results of the CAMUI Trial were presented as an abstract at the 22nd European Meeting on Hypertension and Cardiovascular Protection. The study design (Int Heart J 2012;53:244–8) and the results after 1 year (J Hypertens 2013;31:1245–55) have been published.