Introduction: Impaired baroreflex function is associated with a shift in autonomic balance towards sympathetic dominance, which may play important role in the development of arterial hypertension and consequent target organ damage.
Aim: To determine the effect of treatment on the cardiovascular autonomic modulation expressed by baroreflex sensitivity (BRS) in hypertensives.
Methods: A total of one hundred fourteen hypertensive patients (58 male/56 female, 65 ± 13 years of age, BMI 30 ± 3.4 kg/m(2)) were enrolled. Control group of 20 subjects with normal blood pressure (BP) (ten male/ten female, 59 ± 8 years of age, body mass index 28.3 ± 2.5 kg/m(2)) without any treatment was also studied. BRS and BRSf were determined by the sequence and spectral method: a 5-min on-invasive beat-to-beat recording of blood pressure and R-R interval with use of Collin CBM-7000 monitor, controlled breathing at a frequency of 0.1 Hz.
Results: Significant negative correlation between spontaneous BRS and BP was present in hypertensives (r = -0.52, p < 0.001). All cohort of hypertensive patients had significantly lower BRS than subjects with normal blood pressure (p < 0.05). The greatest decline in BRS values was in hypertensive patients with metabolic syndrome, who had BRS values <5 ms/mmHg. Hypertensives with hypercholesterolaemia on low dose statin therapy (atrovastatin 20 mg) had higher BRS/BRSf values than statin free patients (p < 0.05). Only BRSf not BRS was significantly increased in hypertensives with beta-blockers.
Conclusion: An inverse correlation between blood pressure and BRS is present in hypertensives. BRS and BRSf is higher in low dose statin-treated patients with essential hypertension.
Keywords: Arterial hypertension; Autonomic nervous system; Baroreflex sensitivity; Metabolic syndrome; Statins.