PTSD and the Gut Microbiome

     My father earned two Purple Hearts and a Bronze Star Medal in the Vietnam War. 50 years later, he passed away from a cancer he contracted as a result of the Agent Orange utilized during the war. Like many veterans upon their return home, my father’s life became governed by the terrors of post-traumatic stress disorder (PTSD). PTSD flashbacks disturbed my father’s sleep for the rest of his life, leaving him in a constant state of disequilibrium. A study conducted by Martindale et al., (2020), corroborated my father's experience. Researchers investigated the relationship between the effects of PTSD and sleep outcomes in veterans – they found that PTSD severity was significantly associated with poorer sleep quality (p < .001), restedness (p = .018) and shorter sleep duration (p = .015) (Martindale et al., 2020). Martindale et al., (2020) provides evidence which suggests that veterans would significantly benefit from routine screening of sleep problems and increased emphasis on sleep hygiene. 

    After reading Dr. Vitaterna’s study on the effects of a prebiotic diet on sleep disruption, my first thoughts were of my father. Vitaterna et al. (2022) sought to discover an intervention that improved resilience to insufficient sleep, and this intervention came in the form of a prebiotic diet specifically containing galactooligosaccharides (GOS) and polydextrose (PDX). Rats administered the prebiotic diet demonstrated an increase in sleep during the sleep disruption protocol, wherein the rats were catapulted into a state of disequilibrium through a slow rotating bar at the bottom of their cage that spun for 20 hours a day. Furthermore, this prebiotic diet improved recovery sleep following the sleep disruption protocol. Dr. Vitaterna and her colleagues discovered that a prebiotic diet leads to significant increases in sleep during both the sleep restriction and recovery experimental protocols (Vitaterna et al., 2022) – is it possible that a sort of prebiotic treatment could aid veterans in sleeping more peacefully? As a society, we are governed by a myriad of factors that muddle the sleep/wake cycle. Martindale et al., (2020) elucidate that veterans are particularly vulnerable to disruptions of this precious cycle. This study contributes to a growing body of research identifying a link between the gut microbiome and the regulation of sleep. Thus, this relationship suggests potential for unique therapeutic interventions via the gut microbiome to mitigate disruption of the sleep/wake cycle.

    While there is evidence supporting a link between the gut microbiome and the regulation of sleep, there is a limited body of research that examines the relationship between those whose sleep is most disrupted (PTSD sufferers) and the gut microbiota. A literature review conducted by Halverson and Alagiakrishnan (2020) sought to provide a thorough analysis of the literature on the effect of gut microbiota on mental health and neurocognitive disorders. In this literature review, the authors cite a study wherein human individuals who scored higher on the Clinician Administered Posttraumatic Stress Disorder Scale had lower levels of the gut microbes Actinobacteria, Lentisphaerae and Verrucomicrobia. Halverson and Alagiakrishnan (2020) state that this inverse relationship between increased levels of PTSD and decreased levels of the aforementioned gut bacterias lead to increased vulnerability for PTSD symptoms on account of the decreased anti-inflammatory and immunoregulatory effects these microbiomes possess. 

    Two factors that may contribute to our limited understanding of the relationship between PTSD and the gut microbiome have been elucidated: PTSD severity impacts sleep, and the addition of a prebiotic into the gut microbiome may assist in mitigating disruption to the sleep/wake cycle. Instinctively, every human knows the healing powers of sleep – my father existed in a constant state of disequilibrium because he was deprived of the fundamental necessity to human functioning that is rest. Is it possible that a prebiotic diet could have returned my father to equilibrium and perhaps restored his quality of life? 

References: 

Bowers, S. J., Summa, K. C., Thompson, R. S., González, A., Vargas, F., Olker, C., Jiang, P., Lowry, C. A., Dorrestein, P. C., Knight, R., Wright, K. P., Fleshner, M., Turek, F. W., & Vitaterna, M. H. (2022). A prebiotic diet alters the fecal microbiome and improves sleep in response to sleep disruption in rats. Frontiers in Neuroscience, 16. https://doi.org/10.3389/fnins.2022.889211

Halverson, T., & Alagiakrishnan, K. (2020). Gut microbes in neurocognitive and mental health disorders. Annals of Medicine, 52(8), 423–443. https://doi.org/10.1080/07853890.2020.1808239

Martindale, S. L., Konst, M. J., Bateman, J. R., Arena, A., & Rowland, J. A. (2020). The role of PTSD and TBI in post-deployment sleep outcomes. Military Psychology, 32(2), 212–221. https://doi.org/10.1080/08995605.2020.1724595