Introduction: The objective of this study was to compare the effect on ankle edema of adding valsartan (V) or olmesartan (O) to amlodipine (A) in the treatment of hypertension.
Methods: After a 4-week placebo period, 74 adult outpatients with essential hypertension (diastolic blood pressure [DBP] >90 and <110 mmHg, and systolic blood pressure [SBP] >140 mmHg) were treated with A 10 mg once daily for 4 weeks. Thereafter, nonresponder patients (DBP >90 mmHg and/or SBP >140 mmHg; n=51) were randomized to receive additional V 160 mg once daily or O 20 mg once daily for 8 weeks in two crossover periods, each separated by a 4-week placebo period. Clinic blood pressure (BP), heart rate, and ankle/foot volume (AFV) were evaluated and blood samples were drawn to evaluate plasma norepinephrine (NE) levels.
Results: Both V/A and O/A induced a greater SBP/DBP reduction than A monotherapy (-26.4/-20.8 mmHg and -24.4/-19.1 mmHg, respectively; all P<0.001 vs. baseline and P<0.01 vs. A). A monotherapy increased AFV by 24%, P<0.001 vs. baseline, while the addition of either V or A reduced such increases. However, with V/A the AFV increase (+9.7%, P<0.05 vs. baseline, P<0.01 vs. A) was lower than with O/A (+16.7%, P<0.01 vs. baseline, P<0.05 vs. A); the difference between the two combinations was significant. Plasma NE levels were significantly increased by A (+44.6%) and values did not change with the addition of V (+35.2%) or O (+33.7%). Plasma active renin (PAR) was unchanged by A but increased by V/A (+214.4%, P<0.05 vs. baseline) and further by O/A (+325.6%, P<0.01 vs. baseline; difference between the 2 combinations: P<0.05). An inverse correlation was found between the AFV decrease and PAR increase (r=-0.31, P<0.05).
Conclusion: Adding V or O to A reduced ankle edema, but this effect was more pronounced with V. The greater degree of renin-angiotensin system activation observed with Ocould be related to such a difference.