Acute effects of device-guided slow breathing on sympathetic nerve activity and baroreflex sensitivity in posttraumatic stress disorder
Author: Ida T Fonkoue1 2, Paul J Marvar3, Seth D Norrholm4 5, Melanie L Kankam1 2, Yunxiao Li6, Dana DaCosta1 2, Barbara O Rothbaum5, Jeanie Park1 2
Affiliation:
1 Division of Renal Medicine, Department of Medicine, Emory University School of Medicine , Atlanta, Georgia.
2 Research Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia.
3 Department of Pharmacology and Physiology, Institute for Neuroscience, George Washington University , Washington, District of Columbia.
4 Mental Health Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia.
5 Psychiatry and Behavioral Sciences, Emory University , Atlanta, Georgia.
6 Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University , Atlanta, Georgia.
Conference/Journal: Am J Physiol Heart Circ Physiol
Date published: 2018 Jul 1
Other:
Volume ID: 315 , Issue ID: 1 , Pages: H141-H149 , Special Notes: doi: 10.1152/ajpheart.00098.2018. , Word Count: 343
Patients with posttraumatic stress disorder (PTSD) have elevated sympathetic nervous system reactivity and impaired sympathetic and cardiovagal baroreflex sensitivity (BRS). Device-guided slow breathing (DGB) has been shown to lower blood pressure (BP) and sympathetic activity in other patient populations. We hypothesized that DGB acutely lowers BP, heart rate (HR), and improves BRS in PTSD. In 23 prehypertensive veterans with PTSD, we measured continuous BP, ECG, and muscle sympathetic nerve activity (MSNA) at rest and during 15 min of DGB at 5 breaths/min ( n = 13) or identical sham device breathing at normal rates of 14 breaths/min (sham; n = 10). Sympathetic and cardiovagal BRS was quantified using pharmacological manipulation of BP via the modified Oxford technique at baseline and during the last 5 min of DGB or sham. There was a significant reduction in systolic BP (by -9 ± 2 mmHg, P < 0.001), diastolic BP (by -3 ± 1 mmHg, P = 0.019), mean arterial pressure (by -4 ± 1 mmHg, P = 0.002), and MSNA burst frequency (by -7.8 ± 2.1 bursts/min, P = 0.004) with DGB but no significant change in HR ( P > 0.05). Within the sham group, there was no significant change in diastolic BP, mean arterial pressure, HR, or MSNA burst frequency, but there was a small but significant decrease in systolic BP ( P = 0.034) and MSNA burst incidence ( P = 0.033). Sympathetic BRS increased significantly in the DGB group (-1.08 ± 0.25 to -2.29 ± 0.24 bursts·100 heart beats-1·mmHg-1, P = 0.014) but decreased in the sham group (-1.58 ± 0.34 to -0.82 ± 0.28 bursts·100 heart beats-1·mmHg-1, P = 0.025) (time × device, P = 0.001). There was no significant difference in the change in cardiovagal BRS between the groups (time × device, P = 0.496). DGB acutely lowers BP and MSNA and improves sympathetic but not cardiovagal BRS in prehypertensive veterans with PTSD. NEW & NOTEWORTHY Posttraumatic stress disorder is characterized by augmented sympathetic reactivity, impaired baroreflex sensitivity, and an increased risk for developing hypertension and cardiovascular disease. This is the first study to examine the potential beneficial effects of device-guided slow breathing on hemodynamics, sympathetic activity, and arterial baroreflex sensitivity in prehypertensive veterans with posttraumatic stress disorder.
KEYWORDS: baroreflex; device-guided slow breathing; posttraumatic stress disorder; prehypertension; sympathetic nervous system.
PMID: 29652544 PMCID: PMC6087774 DOI: 10.1152/ajpheart.00098.2018
BACK
