Age-related changes in heart rate variability and spectral parameters of blood pressure variability in the range of 20–90 years

Abstract

The aim of this study was to describe the age and sex characteristics of heart rate variability (HR), systolic and diastolic blood pressure (sBP and dBP), as well as baroreflex sensitivity (BRS).

Methods: Spiroarteriocardiorhythmography recored all reported indicators for each person. The study included 1559 people (1119 women and 440 men) aged 20-90 yrs. The age interval was divided into 10 ranges of 7 yrs each.

Results. Most of the measured variables changed with age. Women had a linear decrease in HR with an increase in BP, but this pattern was not found in men. In both sexes, HR variability had a U-shaped dynamics, i.e., a decrease followed by an increase in SDNN. This reflected the balance of autonomic regulation and total spectrum power, with a minimum at 55–76 yrs. After 62 yrs, an increase in SDNN was observed in the oldest age groups that was associated with vagal activity RMSSD, pNN50, and HF band power. This increase was followed by a decrease in the stress index and the contribution to the HR spectrum of the VLF range. For men aged 34–55 years, the relative contribution of LF to the HR variability spectrum was greater, but in women the contribution of HF was greater. There were corresponding gender effects on values of the LF/HF ratio.

The dependence on age of spectral indicators of BP variability was equal in men and women. In the absence of age-dependent changes of the total power of the variability spectra of both sBP and dBP, a redistribution of the relative power of different ranges was found. There was a linear increase in the contribution of the VLF range, and a decrease after 55 yrs in the contribution of the LF range to the variability spectra of sBP and dBP.

According to the amplitude indicators of baroreflex, the minimum values were recorded for both sexes in the range of 62-69 yrs.

Conclusion. The results indicate a decrease with age after 55 years in the relative contribution of sympathetic influences to regulation of the cardiovascular system that was associated with an increase in the representation of neurogenic vagal and humoral components. The values of the measured indicators in different sexes and ages can be applied in practice as a basis for their normalization.