Age related changes in variability of short-term heart rate and diastolic period

Previous studies have proved that the heart rate variability (HRV) is preferentially expressed in cardiac diastolic period variability (DPV). Does that mean that DPV analysis should act as an alternative approach for characterizing the autonomic regulation? And do they behave in accordance with each other in all subjects with various ages? Our aim was thus to assess the age related changes in: 1) HRV and DPV through frequency domain analysis, and 2) the interactions between HRV and DPV in a nonlinear coupling analysis framework. Totally 60 healthy subjects were enrolled. Results showed that both LF and HF powers of DPV decreased with the increasing of age (both p<;0.001), which behaved generally in the same way with HRV. However, their coupling, especially in terms of short-range correlations (p<;0.01), decreased significantly with aging, which suggests that the interactions between HRV and DPV might provide additional valuable information for characterizing the autonomic regulation in aged individuals.