The association between sympatho-vagal balance and central blood pressures.

Purpose: High central blood pressure is more predictive of cardiovascular disease (CVD) versus high peripheral blood pressure. Measures of central pressures (CPs) include, central systolic blood pressure (CSBP) and central diastolic blood pressure. Measures of central pressures augmentation (CPsA) include augmentation pressure (AP) and the augmentation index @ 75 beats·min-1 (AIx@75). Increased sympathetic tone (ST) is also associated with CVD. The low to high frequency ratio (LF/HF) is often used to determine sympatho-vagal balance. Given the association between ST, CPs, CPsA and CVD there is a need to understand the association between these predictors of CVD. The aims of this study were to examine the association between the LF/HF ratio, CPs, and CPsA in men and women collectively and based on gender.

Methods: We measured the LF/HF ratio, CSBP, AP, and AIx@75 in 102 participants (41F/61M). The LF/HF ratio was determined via power spectral density analysis. CSBP, AP, and AIx@75 were determined via applanation tonometry.

Results: The LF/HF ratio was inversely associated with AP (r = -0.26) and AIx @75 (r = -0.29) in the combined group of men and women. The LF/HF ratio was inversely associated with CSBP (r = -0.27), AP (r = -0.28), and AIx@75 (r = -0.32) in men, but not in women.

Conclusion: There is an inverse association between the LF/HF ratio, AP, and AIx@75 in men and women combined. The association between the LF/HF ratio, CSBP, AP, and AIx@75, differs based on gender.