Elevated resting blood pressure augments autonomic imbalance in posttraumatic stress disorder
Document Type
Journal Article
Publication Date
12-1-2018
Journal
American Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume
315
Issue
6
DOI
10.1152/ajpregu.00173.2018
Keywords
Baroreflex; Heart rate variability; Mental stress; Muscle sympathetic nerve activity; Parasympathetic nervous system; Traumatic stress disorder
Abstract
© 2018, American Physiological Society. All rights reserved. Posttraumatic stress disorder (PTSD) is characterized by increased sympathetic nervous system (SNS) activity, blunted parasympathetic nervous system (PNS) activity, and impaired baroreflex sensitivity (BRS), which contribute to accelerated cardiovascular disease. Patients with PTSD also have chronic stress-related elevations in resting blood pressure (BP), often in the prehypertensive range; yet, it is unclear if elevated resting blood pressure (ERBP) augments these autonomic derange-ments in PTSD. We hypothesized that compared with normotensive PTSD (N-PTSD), those with ERBP (E-PTSD) have further increased SNS, decreased PNS activity, and impaired BRS at rest and exaggerated SNS reactivity, PNS withdrawal, and pressor responses during stress. In 16 E-PTSD and 17 matched N-PTSD, we measured continuous BP, ECG, muscle sympathetic nerve activity (MSNA), and heart rate variability (HRV) markers reflecting cardiac PNS activity [stan-dard deviation of R-R intervals (SDNN), root mean square of differences in successive R-R intervals (RMSSD), and high frequency power (HF)] during 5 min of rest and 3 min of mental arithmetic. Resting MSNA (P = 0.943), sympathetic BRS (P = 0.189), and cardiovagal BRS (P = 0.332) were similar between groups. However, baseline SDNN (56 ± 6 vs. 78 ± 8 ms, P = 0.019), RMSSD (39 ± 6 vs. 63 ± 9 ms, P = 0.018), and HF (378 ± 103 vs. 693 ± 92 ms 2 , P = 0.015) were lower in E-PTSD versus N-PTSD. During mental stress, the systolic blood pressure response (P = 0.011) was augmented in E-PTSD. Although MSNA reactivity was not different (P > 0.05), the E-PTSD group had an exaggerated reduction in HRV during mental stress (P < 0.05). PTSD with ERBP have attenuated resting cardiac PNS activity, coupled with exaggerated BP reactivity and PNS withdrawal during stress.
APA Citation
Fonkoue, I., Norrholm, S., Marvar, P., Li, Y., Kankam, M., Rothbaum, B., & Park, J. (2018). Elevated resting blood pressure augments autonomic imbalance in posttraumatic stress disorder. American Journal of Physiology - Regulatory Integrative and Comparative Physiology, 315 (6). http://dx.doi.org/10.1152/ajpregu.00173.2018