1/f-Modelling of blood pressure and heart rate spectra: Relations to ageing

In this study a validation of the hypothesis that blood pressure (BP) and heart rate (HR) spectra are related to the frequency f according to the K/f^α relation (briefly 1/f) was provided from the analysis of 24-h BP recordings. Frequency bands where the 1/f modelling correctly apply have been identified. Then the 1/f-models and the total power σ² were computed in young and old subjects to quantify the effect of ageing on the BP and HR spectra. Significant differences between the groups were found indicating that physiological changes related to the age not only influence the overall variability but also the 1/f components of the BP and HR spectra.