Effects of Doxazosin and irbesartan on blood pressure and metabolic control in patients with type 2 diabetes and hypertension

The objective of this trial was to compare the metabolic effects of long-term treatment with doxazosin to those of irbesartan in patients with type 2 diabetes and hypertension. We evaluated 96 hypertensive diabetic patients who were randomized to 12 months of double-blind treatment with doxazosin 4 mg/d or irbesartan 300 mg/d. At the end of the study, systolic and diastolic blood pressure (SBP and DBP) were significantly reduced from 152 to 140 mm Hg and from 97 to 87 mm Hg, respectively, with doxazosin (P < 0.01). SBP and DBP were reduced from 150 to 134 mm Hg and from 94 to 83 mm Hg, respectively, with irbesartan (P < 0.01). Irbesartan had significantly better antihypertensive efficacy than doxazosin (P < 0.05). Doxazosin had the greatest effect on glucose metabolism and lipid parameters, with significant (P <= 0.05) reductions observed at study end compared with baseline in glycosylated hemoglobin, fasting plasma glucose, fasting plasma insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and Homeostasis Model Assessment Index. In conclusion, both doxazosin and irbesartan reduced BP during long-term treatment, but not to recommended levels, and doxazosin had the more beneficial effect on glucose metabolism and lipid profile.