Effectiveness of add-on therapy with amlodipine in hypertensive patients receiving valsartan.

Objective: To describe the real-world effectiveness of amlodipine add-on therapy for hypertensive patients receiving valsartan.

Methods: Retrospective cohort study based on USA electronic medical records. The study population included hypertensive patients who, between January 1998 and December 2005, were receiving valsartan and subsequently initiated add-on therapy with amlodipine. Change in systolic blood pressure (SBP)/diastolic blood pressure (DBP), and attainment of goal SBP/DBP (i.e. < 140/90 mmHg), were examined based on last available reading prior to day 180 following initiation of amlodipine.

Results: Mean (+/- SD) baseline SBP/DBP of study subjects (n=155) was 152.5 (+/- 21.1)/84.0 (+/- 13.5) mmHg. Add-on therapy with amlodipine reduced SBP by 13.3 mmHg (95% CI 9.4-17.1) and DBP by 6.1 mmHg (95% CI 4.2-8.1). Among patients with baseline SBP/DBP > or = 160/100 mmHg (n=69), corresponding reductions were 28.8 mmHg (95% CI 23.4-34.2) and 11.4 mmHg (95% CI 8.4-14.3). Goal SBP/DBP was achieved by 46% (95% CI 37.7-55.6) of subjects; rates of goal attainment were similar for patients with and without diabetes or chronic kidney disease, and those aged > or = 65 years versus younger.

Conclusions: Adding amlodipine to valsartan for treatment of hypertension results in clinically meaningful reductions in blood pressure, on an overall basis and in high-risk subgroups who may benefit the most from blood pressure control.