A multicenter, community-based study of doxazosin in the treatment of concomitant hypertension and symptomatic benign prostatic hyperplasia: the hypertension and BPH intervention trial (HABIT)

Abstract

As men age, the incidence of both benign prostatic hyperplasia (BPH) and hypertension increases. Concomitant occurrence of these conditions also increases with age, and the 2 are frequently encountered together in primary care practice. In addition, many patients with hypertension require >1 antihypertensive agent to adequately control blood pressure. In a multicenter, community-based, 8-week, uncontrolled, open-label study, we evaluated doxazosin, a selective alpha 1aadrenergic-receptor antagonist, in 491 patients with concomitant symptomatic BPH (American Urological Association [AUA] symptom score ≥ 12) and hypertension, some previously untreated and some with inadequately controlled hypertension (systolic blood pressure 120–179 mm Hg or diastolic blood pressure [DBP] 80–109 mm Hg) despite taking 1 or 2 antihypertensive agents. Patients were allocated to 1 of 4 groups at baseline according to their diastolic blood pressure (control was considered DBP < 90 mm Hg) and whether they had received antihypertensive medication before the study. Thus the 4 groups were treated/well-controlled, treated/poorly controlled, untreated/hypertensive, and untreated/normotensive. In all patient groups, doxazosin therapy significantly improved AUA total symptom and bothersomeness scores and BPH-specific indices of health status and interference with activities ( P < 0.001). Significant improvements in BPH symptoms were observed with doxazosin, regardless of whether initial symptoms were moderate or severe ( P < 0.001). Clinically important blood pressure lowering occurred only in the patient groups in which blood pressure had been elevated at baseline. Patients whose blood pressure was poorly controlled at baseline, either without or with treatment (predominantly with angiotensin-converting enzyme inhibitors or calcium channel blockers), achieved adequate blood pressure control (reduction to < 140/90 mm Hg) with the addition of doxazosin. Similar improvements in blood pressure and BPH symptoms were seen in both older (≥ 65 years) and younger (45 to 64 years) patients, and doxazosin was well tolerated by both groups. The most frequent treatmentrelated adverse event was dizziness (13.0% of patients); however, patients classified the dizziness as mild in 75% of reports, and severe dizziness was reported by only 2 patients (0.4%). Doxazosin is an effective antihypertensive agent when used in combination with agents from other antihypertensive classes in patients with poorly controlled hypertension and BPH, and is also successful as monotherapy for controlling both BPH and hypertension in patients with mild to moderate hypertension.