Comparison of Heart Rate Variability in Thai Older Adults with Hypertension, Pre-Hypertension, and Normotension

Table 3

Correlation of the HRV index with BP parameters of the study population.

	SBP		DBP		PP		MAP
	r	value	R	value	r	value	r	value
Time domain
SDNN (ms)	−0.49	<0.01	−0.35	<0.01	−0.42	<0.01	−0.24	0.05
RMSSD (ms)	−0.25	0.05	−0.22	0.08	−0.19	0.13	−0.23	0.07
pNN50 (%)	−0.36	<0.01	−0.29	0.02	−0.29	0.02	−0.27	0.03
Frequency domain
LF power (ms^2)	−0.44	<0.01	−0.20	0.12	−0.46	<0.01	−0.10	0.45
HF power (ms^2)	−0.43	<0.01	−0.29	0.02∗	−0.38	<0.01	−0.23	0.07
LF/HF ratio	−0.05	0.72	0.08	0.51	−0.11	0.37	0.10	0.42

Analysis was performed using Pearson’s correlation analysis. , . BP, blood pressure; SBP, systolic blood pressure; DBP, diastolic blood pressure; PP, pulse pressure; MAP, mean arterial pressure; SDNN, standard deviation of NN intervals; RMSSD, root mean square of successive RR interval differences; pNN50, percentage of successive RR intervals that differ by more than 50 ms; LF power, low frequency; HF power, high frequency; LF/HF, ratio of LF-to-HF power.