Atorvastatin reduces sympathetic activity and increases baroreceptor reflex sensitivity in patients with hypercholesterolaemia and systemic arterial hypertension

Abstract

Background: Increased sympathetic activity might be related to pathogenesis of hypertension as well as to end organ damage. Animal studies suggest that statins decrease sympathetic activity and increase baroreceptor reflex sensitivity (BRS).

Aim: To examine whether atorvastatin decreases muscle sympathetic nerve activity (MSNA) and BRS in hypercholesterolaemic and hypertensive patients.

Methods: Ten patients with essential hypertension and untreated hypercholesterolaemia (aged 43 +/- 12 years) and eight healthy subjects (aged 37 +/- 7 years) were enrolled in the study. In both groups the recordings of microneurography, ECG, blood pressure and BRS were performed twice, before and after 8 weeks during which the patients (but not controls) were treated with atorvastatin.

Results: Compared with controls, the patients had higher MSNA values (36.0 +/- 6.6 vs. 29.8 +/- 3.7 bursts/minute), mean BP levels (145.1 +/- 10 vs. 124.1 +/- 11.1 mmHg) and total cholesterol concentration (252.6 +/- 22.6 vs. 179.8 +/- 20.7 mg/dl) baseline values. Statin therapy resulted in a decrease of total cholesterol (252.6 +/- 22.0 vs. 173.8 +/- 26.2 mg/dl, p < 0.05) and MSNA (36.0 +/- 6.6 vs. 28.6 +/- 4.8 bursts/min, p < 0.05), whereas BRS values were increased (12.6 +/- 5.6 vs. 18.1 +/- 5.9 ms/mmHg, p < 0.05). Post-treatment BRS was inversely related to post-treatment MSNA (r = -0.73, p < 0.05). In the controls there were no changes in MSNA (29.8 +/- 3.7 vs. 28.9 +/- 2.9 bursts/min), BRS (11.9 +/- 5.0 vs. 13.1 +/- 4.8 ms/mmHg), total cholesterol, BP and heart rate between the first and the second measurement.

Conclusion: Atorvastatin reduces MSNA and increases BRS in hypertensive and hypercholesterolaemic patients. Decrease in sympathetic activity may be the result of improvement of baroreceptor function by atorvastatin.