Impaired baroreflex function and arterial compliance in primary aldosteronism

The purpose of this study was to evaluate if changes in vascular properties were related to baroreflex function in patients with primary aldosteronism . Twenty-three patients with primary aldosteronism, 22 essential hypertensi ve patients and 16 normal controls were studied. Continuous finger blood pr essure (BP) was recorded by Portapres device during supine rest and active stand up. Compliance was estimated from the time constant of pressure decay during diastole. Baroreflex sensitivity was calculated by autoregressive c ross-spectral analysis of systolic BP and interbeat interval. The result wa s that baroreflex gain and compliance were lower in primary aldosteronism p atients in the supine position (P 0.002 and P < 0.05 respectively). Aldoste rone plasma levels (R-2 = 0.31, P = 0.01), age, systolic and diastolic BP, high and low frequency components of diastolic BP variability were independ ently related to compliance in primary aldosteronism. In conclusion primary aldosteronism is associated with an impaired baroreflex function related i n part to a reduced arterial compliance. Despite a reduction of BP values a nd aldosterone levels, surgical or pharmacological treatment did not signif icantly change compliance values.