Role of the autonomic nervous system in young, middle-aged, and older individuals with essential hypertension and sleep-related changes in neurocardiac regulation

Figures

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  Figure 1. Influence of age and hypertension on HRV parameters in young, middle-aged, and older participants. For each group of samples (CON, HTN), each bar represents the average means of the parameters within the corresponding age range. 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, CON control group, HTN hypertension group. Data are presented as mean ± SEM, two-way ANOVA. *p < 0.05 HTN vs. CON. (A) p < 0.05 main effect of age, vs. 30–39; (B) p < 0.05 main effect of age, vs. 40–59. HTN vs. CON p < 0.05 main effect of HTN.

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  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.

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  Figure 3. Effects of age and hypertension on arterial pressure variability/BRS parameters in young, middle-aged, and older men. Each bar in the graph represents the average values of the parameters within the respective age range for each group (HTN vs. CON). ln natural logarithm, BP blood pressure, BLF LF of arterial pressure variability, BrrLF/BrrHF magnitude of mean arterial pressure—R–R interval transfer function, BrrA/BrrD slope of mean arterial pressure—R–R interval linear regression, AW wakefulness, nREM nonrapid eye movement sleep, CON control group, HTN hypertension group. Data are presented in terms of the mean ± SEM values. (A) p < 0.05 main effect of age, vs. 30–39; (B) p < 0.05 main effect of age, vs. 40–59. a p < 0.05 vs. 30–39, least-significant difference post hoc test. *p < 0.05 vs. control of the same age group, independent-samples t test.

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  Figure 4. Two-dimensional scatter plots depicting the correlations between arterial pressure variability/BRS parameters and age. *p < 0.05. rCON correlation coefficient of the control group, rHTN correlation coefficient of the hypertension group, ln natural logarithm, BP blood pressure, BLF LF of arterial pressure variability, BrrLF/BrrHF magnitude of mean arterial pressure—R–R interval transfer function, BrrA/BrrD slope of mean arterial pressure—R–R interval linear regression, AW wakefulness, nREM nonrapid eye movement sleep.