Effects of doxazosin on orthostatic blood pressure in hypertensive patients with and without diabetes mellitus

Abstract

Alpha 1-blockers are thought to cause the orthostatic hypotension frequently observed in patients with hypertension. We studied the degree to which doxazosin reduced the blood pressure in hypertensive patients with diabetes mellitus (HDM [+]) and without diabetes mellitus (HDM [−]), when they were placed in a standing position. Seven HDM (−) patients and eight HDM(+) patients were included in this study. After diagnosis, a blood pressure—monitoring system for ambulatory patients was attached to each patient. Blood pressure was measured, first with patients in a supine position and again 2 and 4 minutes after standing. The same procedure was performed on each patient after 12 weeks of doxazosin treatment. The mean dose of doxazosin was 2.1 ± 1.5 mg for HDM(−) patients and 2.4 ± 2.5 mg for HDM(+) patients. Treatment with doxazosin resulted in a significant sitting blood pressure reduction as measured by the ordinary cuff method. Doxazosin caused no statistically significant orthostatic systolic blood pressure reduction at 2 minutes after standing for HDM(−) patients (15 ± 5 mm Hg [control] vs 16 ± 4 mm Hg [treatment]) and for HDM(+) patients (7 ± 15 mm Hg [control] vs 8 ± 14 [treatment]), respectively). We concluded doxazosin did not have a statistically significant effect on the orthostatic blood pressure reduction for both HDM(−) patients and HDM(+) patients with respect to the doses used.