Differential impact of angiotensin receptor blockers and calcium channel blockers on arterial stiffness.

AIM

Arterial stiffness, assessed by ambulatory arterial stiffness index (AASI), is an independent predictor of cardiovascular disease (CVD) mortality in hypertensives. However, it is unclear whether certain antihypertensive drugs are conducive to the reduction in CVD morbidity and mortality through their beneficial effect on arterial stiffness. Therefore, we compared the effect of angiotensin receptor blockers (ARBs) and calcium channel blockers (CCBs) on AASI in a hypertensive population.

METHODS

We studied 188 individuals with newly-diagnosed essential hypertension without organ damage or CVD. AASI was calculated from twenty-four-hour ambulatory blood pressure monitoring (ABPM) readings at baseline and after twelve weeks of antihypertensive treatment. Therapy was initiated with a low-dose of CCB (group A) or ARB (group B). After six weeks, subjects with poor office blood pressure (BP) control were further randomized to high-dose monotherapy (CCB in group C or ARB in group D) or low-dose combination therapy (CCB plus ARB, group E).

RESULTS

Groups A and B showed similar reductions in systolic and diastolic BP (r=-0.12, P=0.92 and r=-0.07, P=0.58 in group A and r=-0.06, P=0.67 and r=-0.04, P=0.73 in group B, respectively). However, only subjects in group B achieved significant AASI decrease (P<0.001). Similarly, subjects in groups C, D and E also displayed a comparable BP reduction, but only those in group E attained significant AASI decrease (P=0.001).

CONCLUSION

ARB treatment, either as low-dose monotherapy or in combination with a CCB in hypertensives who do not achieve BP control with monotherapy, has a beneficial effect on arterial stiffness. As arterial stiffness is an important modifiable risk factor, our findings highlight the value of ARBs beyond their BP lowering properties.