Free
The Somatic Connection  |   October 2017
Physiologic Effects of Posttraumatic Stress Disorder in Veterans
Author Notes
  • Western University of Health Science College of Osteopathic Medicine of the Pacific-Northwest, Lebanon, Oregon 
Article Information
The Somatic Connection   |   October 2017
Physiologic Effects of Posttraumatic Stress Disorder in Veterans
The Journal of the American Osteopathic Association, October 2017, Vol. 117, 665-666. doi:10.7556/jaoa.2017.125
The Journal of the American Osteopathic Association, October 2017, Vol. 117, 665-666. doi:10.7556/jaoa.2017.125
Park J, Marvar PJ, Liao P, et al. Baroreflex dysfunction and augmented sympathetic nerve responses during mental stress in veterans with post-traumatic stress disorder. J Physiol. 2017;595(14):4893-4908. doi:10.1113/JP274269 
Historically, osteopathic manipulative treatment (OMT) techniques that address key areas of autonomic nervous system dysfunction have been thought to be helpful in controlling stress reactions in humans. Techniques such as the occiptoatlantal release, rib raising articulatory, and thoracic pump techniques have been shown to lower human secretory immunoglobulin A (IgA) level. Secretory IgA has been shown to have an inverse relationship between stress and level of mucosal secretory IgA.1 Heart rate variability has been shown to decrease when human participants are stressed but has been shown to improve with OMT techniques that address the cervical spine.2 
People who serve in the United States Armed Forces are often exposed to harrowing conditions that have unanticipated lasting effects on many facets of their lives. A 2008 publication3 reported that 11% to 20% of service members with posttraumatic stress disorder (PTSD) experience multiple effects on their physiologic state. One of those effects may be poor cardiovascular health.4 Researchers5 at Emory University and the Atlanta VA Medical Center proposed a link between PTSD and an overactive sympathetic nervous system, as well as impaired baroreflex sensitivity (BRS), which may account for the high rates of hypertension and cardiovascular disease in veterans with PTSD. 
In this study, 14 veterans with PTSD without comorbidities were matched with 14 similar controls without PTSD. Electrocardiography results were obtained and muscle sympathetic nerve activity (MSNA) of the peroneal nerve and continuous blood pressure were measured at baseline and again while the veterans were exposed to 2 distinct types of mental stress: combat-related (through virtual reality combat exposure [VRCE]) and non–combat-related (through solving an arithmetic problem). A cold pressor test was also administered to evaluate a scientifically established cause of systemic sympathetic activation. Baroreflex sensitivity was evaluated at rest and during VRCE via pharmacologic manipulation using a bolus intravenous infusion of sodium nitroprusside followed by a bolus infusion of phenylephrine hydrochloride 60 seconds later, which is known as the “modified Oxford technique.” Blood samples were also taken to assess C-reactive protein, IL-2, and IL-6, which are known inflammatory biomarkers. 
Veterans with PTSD had an overactive sympathetic nervous system and blunted BRS. Although the baseline values were similar between the 2 groups, the veterans with PTSD had significantly elevated MSNA (P<.001) and heart rate (P=.003) responses during VRCE. Similarly, there was a significant difference between MSNA (P<.001) and diastolic blood pressure response (P=.011) during mental arithmetic in veterans with PTSD vs those without PTSD but not during the cold pressor test. Veterans with PTSD also exhibited a blunted sympathetic BRS (P=.026) and cardiovagal BRS (P=.008) at rest, as well as elevated levels of C-reactive protein (P=.047) compared with controls. Limitations included small sample size, predominance of African American men in the sample, and the presence of subthreshold PTSD in the control group. 
Specific OMT techniques, such as OA decompression and rib raising, may affect the autonomic nervous system by lowering sympathetic nervous system activity. Because this investigation revealed that veterans with PTSD have heightened sympathetic responses, the potential exists for OMT to improve the cardiac health of veterans.6 Further studies are needed to investigate the benefits of OMT techniques in inhibiting sympathetic outflow. 
References
Saggio G, Docimo S, Pilc J, Norton J, Gilliar W. Impact of osteopathic manipulative treatment on secretory immunoglobulin A levels in a stressed population. J Am Osteopath Assoc. 2011;111(3):143-147. [PubMed]
Giles PD, Hensel KL, Pacchia DF, Smith ML. Suboccipital decompression enhances heart rate variability indices of cardiac control in healthy subjects. J Altern Complement Med. 2013;19(2):92-96. doi: 10.1089/acm.2011.0031 [CrossRef] [PubMed]
Tanielian T, Jaycox LH, eds. Invisible Wounds of War: Psychological and Cognitive Injuries, Their Consequences, and Services to Assist Recovery. Santa Monica, CA: RAND Corp; 2008. https://www.rand.org/content/dam/rand/pubs/monographs/2008/RAND_MG720.pdf. Accessed August 28, 2017.
Coughlin SS. Post-traumatic stress disorder and cardiovascular disease. Open Cardiovasc Med J. 2011;5:164-170. doi: 10.2174/1874192401105010164 [CrossRef] [PubMed]
Young CN, Fisher JP, Fadel PJ. The ups and downs of assessing baroreflex function. J Physiol. 2008;586(5):1209-1211. doi: 10.1113/jphysiol.2007.149484 [CrossRef] [PubMed]
Joyner MJ, Charkoudian N, Wallin BG. Sympathetic nervous system and blood pressure in humans: individualized patterns of regulation and their implications. Hypertension. 2010;56(1):10-16. doi: 10.1161/hypertensionaha.109.140186 [CrossRef] [PubMed]