Figure 2

Two-dimensional scatter plots depicting the correlations between HRV parameters and age. *p < 0.05. rCON correlation coefficient of the control group, rHTN correlation coefficient of the hypertension group, RR R–R intervals, TP total power, LF low frequency, HF high frequency, LF/HF LF to HF ratio, LF% normalized LF, AW wakefulness, nREM nonrapid eye movement sleep.