Defining the antihypertensive properties of the angiotensin receptor blocker telmisartan by a practice-based clinical trial

Abstract

Traditional randomized controlled clinical trials are designed to define the specific properties of individual antihypertensive drugs, but do not provide full information about their use in clinical practice. To evaluate the safety and efficacy of an angiotensin receptor blocker in controlling blood pressure (BP) in the community setting, this practice-based open-label study was performed by 703 practitioners in 2642 hypertensives patients. Patients were untreated at the time of study entry with BP ≥140/90 mmHg (N-1957) or were treated but uncontrolled on current monotherapy (N=−685). After stopping any previous treatment, patients received telmisartan 40 mg daily for 2 weeks; the dose was increased to 80 mg if BP remained ≥130/85 mmHg. Participants were then followed for a 4 week maintenance period. The BP fell by 18.9/12.3 mmHg in the untreated groupand by 13.1/7.9 mmHg in the previously treated but uncontrolled group. Patients not responding adequately to the 40 mg telmisartan dose had an initial BP reduction of 7.3/4.5 mmHg; titration to 80 mg gave an additional 7.5/5.0 mmHg reduction and controlled BP (<140/90 mmHg) in 44% of these patients. Overall, control occurred in 56% of white patients; 52% of black patients (who responded very well to dose up-titration); 60% of patients <65 years; and 46% in patients ≥65 (who, despite protocol requirements, were the patients least likely to get the higher dose). Thus, in contrast with randomized controlled trials using parallel group designs, this practice-based trial clearly demonstrates the value of titrating an ARB to maximal dose in patients with inadequate BP responses to the initial dose and emphasizes the benefit of structured treatment protocols in the practice setting.