Effects of sympatholytic therapy on insulin sensitivity indices in hypertensive postmenopausal women

Cardiovascular risk factors are often ineffectively controlled in hypertensive postmenopausal women, and moreover, some antihypertensive drugs may increase particular risk factors such as insulin resistance. In a multicenter, multinational (Finland, Sweden, Lithuania), double-blind, prospectively randomized study hypertensive obese postmenopausal women without hormone therapy (n = 98) were randomly assigned to receive treatment with either the centrally acting agent moxonidine, 0.6 mg/day, or with the peripherally acting atenolol, 50 mg/day, for 8 weeks. In addition to blood pressure measurements, insulin sensitivity was estimated by the quantitative insulin sensitivity check index (QUICKI) and by the insulin sensitivity index (ISI-Matsuda). Subgroup analysis in insulin-resistant women (fasting P-insulin > or = 10 mU/l) and blood pressure responders (diastolic blood pressure < or = 90 mmHg and/or reduction of blood pressure > or = 10 mmHg) were also carried out. Both atenolol and moxonidine led to a significant reduction in diastolic blood pressure of 9.5 mmHg and 6.2 mmHg, respectively. Among insulin-resistant women, an increase in the insulin sensitivity assessed by ISI was improved with moxonidine treatment (p = 0.025). A decrease in insulin sensitivity assessed by QUICKI was observed with atenolol treatment in women with fasting insulin level < 10 mU/l. In patients, in whom blood pressure was reduced, an improvement in insulin sensitivity (ISI) was associated with moxonidine treatment (p = 0.019), but not with atenolol treatment. The centrally acting sympatholytic agent moxonidine did reduce blood pressure somewhat less than atenolol, but it was associated with an improved metabolic profile in terms of decreased insulin resistance both in insulin-resistant postmenopausal women and in women with a significant blood pressure response.