We aimed to evaluate the hypotensive effect and the time to attain the maximal antihypertensive effect (stabilization time) of 8 mg candesartan/6.25 mg hydrochlorothiazide (HCTZ) combination therapy (combination regimen) and therapy with an increased candesartan dose (12 mg; maximum dose regimen) using home blood pressure (BP) measurements. A prospective, multicenter, open-label, randomized, comparative trial was conducted. Essential hypertensive patients who failed to achieve adequate BP control (systolic BP (SBP) ≤135 mm Hg) on 8 mg candesartan alone were randomized to two groups: the combination regimen (n=103) and the maximum dose regimen (n=103). Home morning SBP reduction at 8 weeks after randomization was 11.4±1.3 mm Hg in the combination regimen and 7.8±1.2 mm Hg in the maximum dose regimen. The combination regimen provided additional reduction of 4.0 mm Hg (95% confidence interval (CI): 0.8-7.2 mm Hg, P=0.01) in home morning SBP over the maximum dose regimen at 8 weeks after randomization. The maximal antihypertensive effect and stabilization time for home SBP were 9.4 mm Hg and 37.1 days (P<0.0001), respectively, with the combination regimen. The maximum dose regimen decreased home SBP with a very gentle slope, and estimated maximal effect and estimated stabilization time were not significant (P>0.2). The rate of achieving target BP (home morning SBP <135 mm Hg) was significantly higher with the combination regimen than with the maximum dose regimen (52.4 vs. 30.1%, P=0.002). In conclusion, changing from 8 mg candesartan to combination therapy was more effective in reducing home SBP and achieving goal BP more rapidly than increasing the candesartan dose.
- angiotensin II receptor blockers
- candesartan/hydrochlorothiazide combination
- home blood pressure measurement randomized controlled trial
- stabilization time