Issue 178 Item 11 Doxazosin Improves Insulin Resistance in Hypertensive Patients

Jun 23, 2004
1,389 views

Doxazosin, an alpha-adrenergic blocking agent, appears to have a beneficial effect on adipose endocrine activity and may improve insulin resistance and dyslipidaemia in obese hypertensive patients. Adipose tissue is now recognized as a site of endocrine activity that secretes tumor necrosis factor alpha, leptin, and other factors that may be associated with insulin resistance. The ability of an antihypertensive drug to influence insulin resistance is an important consideration when treating hypertensive patients with type 2 diabetes.

Hajime Ueshiba, MD, with the Toho University School of Medicine, Tokyo, Japan, and colleagues determined the effect of doxazosin on insulin resistance in 19 hypertensive obese patients, with blood pressure (BP) >160/90 mmHg and mean body mass index of 26.7 ± 1.9 kg/m2.

Patients received doxazosin 4 mg/day for 12 months. Systolic BP decreased from 169 ± 10.8 mmHg to 147 ± 11.9 mmHg (p < 0.0001) and diastolic BP decreased from 102 ± 8.1 mmHg to 87 ± 5.0 mmHg (p < 0.0001).

In addition, insulin resistance (p = 0.022) and fasting immunoreactive insulin (p = 0.046) were significantly lower at study end compared to baseline as was total cholesterol. Circulating TNF-alpha and leptin levels decreased significantly within 3 months of treatment, whereas leptin was independently associated with insulin resistance when adjusted for BMI.

"The use of doxazosin for treatment of hypertension will result in less interference with glucose metabolism while having the benefit of potentially improving dyslipidemia and decreasing cardiovascular risk," the researchers conclude. The mechanism underlying the effect of alpha-adrenoreceptor inhibition on insulin resistance is unknown, but it may result from systemic arteriole relaxation, which increases blood flow and tissue responses to glucose.

"Improvement in insulin sensitivity and decreased VLDL production are the most likely underlying mechanisms responsible for the influence of doxazosin on lipid metabolism," they note.

Horm Metab Res 2003;35:9:532-536

================================

Did YOU KNOW:
Breast-Feeding Does Not Affect Childhood Obesity
Data from two new studies do not support the theory that breast-feeding protects children from obesity.
Recent reports have suggested that breast-feeding may lower the risk of adiposity in childhood and adolescence, researchers note in the October 18th issue of the British Medical Journal, but the evidence is not consistent.