Doxazosin in Hypertension: Results of a General Practice Study in 4809 Patients

Abstract

SUMMARY The safety and efficacy of the selective α1‐adrenoceptor antagonist doxazosin were evaluated in a 10‐week open, non‐comparative multicentre trial in 4809 hypertensive patients (sitting diastolic blood pressure 95–114 mmHg) in general practice. Multiple coronary risk factors were present in the study population (mean age 58.4 years, 1486 patients ≥65 years) on entry: mean blood pressure was 173/103 mmHg, 21% were cigarette smokers, and baseline blood cholesterol (mean 6.84 mmol/l) exceeded 6.5 mmol/l in 56% and 5.2 mmol/l in 88% of patients. In all, 4385 patients (91%) completed the study, including 89% of those ≥65 years. Blood pressure was controlled (diastolic BP ≤90 mmHg or a reduction ≥10 mmHg) in 81% of patients with a mean reduction of 21/15 mmHg and a mean final daily dose of 2.9 mg doxazosin. Adverse events were reported in 827 patients (17%), were severe in 72 (1.5%), and led to withdrawal in 269 patients (5.7%). Dizziness and related symptoms (6%; severe 1.1%), headache (3.8%) and fatigue (2.6%) were most frequent; dizziness led to study withdrawal in 1.3% of patients. Fainting or syncope occurred in 13 patients (0.3%). Differences in adverse event frequency between younger (<65) and older patients were small (dizziness: younger 5.1%, older 8.1%). Troublesome postural hypotension was uncommon as a clinical problem. Modest but statistically significant reductions occurred in blood total (4.09%) and LDL (5.13%) cholesterol. These results are in accord with those of controlled studies, and help confirm the suitability of doxazosin as part of a multiple risk factor approach to the management of hypertension.