Effect of telmisartan addition to amlodipine on ankle edema development in treating hypertensive patients

The objective of this research was to evaluate the effect of telmisartan addition to amlodipine, on peripheral edema in hypertensive patients.Seventy-five outpatients were randomized to amlodipine (A) 10 mg or telmisartan (T) 80 mg, or amlodipine 10 mg plus telmisartan 80 mg, for 6 weeks, in three crossover periods.Blood pressure, ankle foot volume (AFV) and pretibial subcutaneous tissue pressure (PSTP) were evaluated, as were plasma norepinephrine and plasma active renin (PAR).Amlodipine-telmisartan combination induced greater SBP/DBP reduction (-28.1/21.7 mmHg, p < 0.0001 vs baseline) compared with monotherapy with both amlodipine and telmisartan. Amlodipine monotherapy increased AFV by 26.7\%, and PSTP by 83.2\% (both p < 0.01). Adding telmisartan to amlodipine produced a significantly lesser increase in both AFV (+7.9\%, p < 0.01 vs amlodipine) and PSTP (+23.8\%, p < 0.01 vs amlodipine). Plasma norepinephrine levels were increased by amlodipine (+134.3 pg/ml, p < 0.01); such an increase was attenuated by the addition of telmisartan (+55 pg/ml, p < 0.05 vs amlodipine). PAR was slightly increased by amlodipine (+21.5 pg/ml, p < 0.05) and more by telmisartan alone (+62.5 pg/ml) and telmisartan-amlodipine combination (+71.3 pg/ml; both p < 0.01).The addition of telmisartan to amlodipine significantly attenuated amlodipine-induced edema formation. The reduction of amlodipine-induced reflex-sympathetic activation by telmisartan might have contributed to such an effect.