title: Effects of amlodipine and candesartan on arterial stiffness estimated by cardio-ankle vascular index in patients with essential hypertension: A 24-week study.
abstract: BACKGROUND
  Aortic stiffness assessed by brachio-ankle pulse wave velocity (baPWV) can be used to predict cardiovascular events. However, baPWV is dependent on blood pressure. Antihypertensive drugs have been reported to reduce baPWV; but it is difficult to determine if this effect is associated with lowered blood pressure or reduced arterial stiffness.
  
  
  OBJECTIVE
  The primary end point of this study was to assess whether antihypertensive drugs reduce arterial stiffness as estimated by cardio-ankle vascular index (CAVI). The secondary end point was to compare the effects of 2 widely used drugs, the calcium-channel blocker amlodipine and the angiotensin II receptor blocker candesartan, on arterial stiffness.
  
  
  METHODS
  Between October 2005 and September 2006, consecutive Japanese outpatients with essential hypertension (EHT) (defined as using antihypertensive drugs at screening, systolic blood pressure [SBP] > 140 mm Hg, or diastolic BP [DBP] >90 mm Hg) were assigned to treatment for 24 weeks with either amlodipine (5-10 mg/d) or candesartan (8-12 mg/d). Arterial stiffness was evaluated with CAVI before and after 24 weeks of treatment. Relative change in arterial stiffness from baseline was also compared. The evaluator was blinded to treatment.
  
  
  RESULTS
  Twenty patients (11 men, 9 women; mean [SD] age, 62 [10] years) were included in the study. There were no significant differences in clinical characteristics between the 2 groups. At baseline, mean (SD) CAVI was not significantly different in the amlodipine group compared with the candesartan group (8.93 [0.93] vs 8.46 [1.34], respectively). During the 24-week treatment period, mean SBP and DBP decreased significantly in both the amlodipine (14/10 mm Hg; P = 0.006 and P = 0.005) and the candesartan groups (13/11 mm Hg; P = 0.033 and P = 0.005). Amlodipine was associated with a significant change in CAVI from baseline (8.93 [0.93] vs 8.60 [1.50]; P = 0.017), whereas candesartan was not (8.46 [1.34] vs 8.81 [1.20]). The percentage change in CAVI was significantly different in the amlodipine group compared with the candesartan group (-7.14 [8.83] vs 5.85 [16.0], respectively; P = 0.038). After 24 weeks of treatment, the CAVI of the amlodipine group was still numerically larger than baseline CAVI of the candesartan group, although the difference was not statistically significant. Furthermore, there was no significant difference in absolute CAVI between the 2 groups after 24 weeks, but the relative change from baseline was significant in favor of amlodipine. Logistic regression analysis revealed that amlodipine improved CAVI independent of its antihypertensive effect.
  
  
  CONCLUSIONS
  These data suggest that amlodipine and candesartan had different effects on aortic stiffness estimated by CAVI, despite similar effects on brachial blood pressure after 24 weeks of treatment in these Japanese patients with EHT.
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Mie
authors.initials: M
authors.lastname: Kurata
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Okura
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Sanae
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Irita
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Daijiro
authors.initials: D
authors.lastname: Enomoto
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Johtoku
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Miyoshi
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Mitsuko
authors.initials: M
authors.lastname: Koresawa
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Tomikazu
authors.initials: T
authors.lastname: Fukuoka
authors.affiliation: Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
authors.forename: Jitsuo
authors.initials: J
authors.lastname: Higaki
keywords: amlodipne; arterial stiffness; candesartan; cardio-ankle vascular index