The Body Keeps The Score: Immune responses to PTSD

Traumatic experiences leave invisible scars that often require psychological intervention for healing. Patients with post-traumatic stress disorder (PTSD) often report feeling unsafe living in their own bodies due to the numbness and frequent flashbacks. Boston’s Dr. Bessel van der Kolk, author and leading expert on traumatic stress, argues that “trauma changes the way people perceive themselves, others, and the world,” and emerging science increasingly supports the idea that these changes manifest in ways beyond PTSD. A growing body of research suggests that trauma’s toll isn’t just psychological — it can be physiological too. Although more is known about stress’s impact on cardiovascular health, its invasive effects on the immune system remain less explored but equally potent.

Dr. van der Kolk’s influential novel “The Body Keeps the Score” explores the extensive ways trauma impacts his patients. He draws on decades of research and experience working with patients, particularly veterans, to illustrate how “trauma changes the way people perceive themselves, others, and the world.” For instance, the autonomic nervous system — responsible for regulating involuntary bodily functions — often becomes hyperactive in trauma survivors, contributing to issues like irritable bowel syndrome, chronic fatigue, and cardiovascular diseases. 

One striking case involves a patient, Marilyn, working through repressed childhood memories triggered by an intimate encounter. After several months, Marilyn began to lose vision, causing her several injuries. After an evaluation from Mass Eye and Ear, she was diagnosed with lupus erythematous of the retina. The condition, largely genetic, occurs when the body mistakenly identifies its own healthy cells as threats, causing devastating cycles of flares and remissions. Dr. van der Kolk noted that Marilyn was the third patient that year with a history of incest and subsequent autoimmune disease. He was struck by the pattern: all three patients exhibited an unusual balance of RA (regulatory T) cells to RO (reactive T) cells, suggesting a link between trauma, immune dysregulation, and chronic disease. Regulatory T cells help suppress excessive immune responses, while reactive T cells attack infected or abnormal cells. Excessive activation of reactive T cells and a decline in regulatory T cells may exacerbate inflammation and trigger autoimmune processes.

“Dr. van der Kolk’s work serves as a powerful reminder that trauma doesn’t just linger in the mind — it imprints itself on the body in profound ways.”

Recent research supports this intersection between PTSD, immune, and endocrine systems. Dr. Seyma Katrinli and colleagues continued this research, focusing on cytokines and inflammatory responses to trauma. In a healthy immune system, cytokines ensure that the body can respond effectively to infections without causing unnecessary inflammation. However, chronic psychological stress can lead to an overproduction of proinflammatory cytokines, such as interleukin–6 (IL–6) and tumor necrosis factor-alpha (TNF–α). This persistent inflammation can damage tissues, disrupt normal immune function, and increase the risk of autoimmune diseases.

For patients like Marilyn, immune dysfunction appears linked to her history of childhood abuse, suggesting trauma sensitizes the body and leaves it vulnerable to physical illness. This interconnectedness underscores the need for integrated treatment approaches, as discussed in “The Body Keeps the Score.” Trauma’s impact is rarely confined to one system; rather, it has a ripple effect, influencing multiple physiological pathways. Interventions like EMDR (Eye Movement Desensitization and Reprocessing), somatic therapies, and mindfulness-based stress reduction not only alleviate psychological symptoms but may also mitigate the correlated physiological consequences of trauma by reducing systemic inflammation and rebalancing the HPA axis.

Dr. van der Kolk’s work serves as a powerful reminder that trauma doesn’t just linger in the mind — it imprints itself on the body in profound ways. “If the memory of trauma is encoded in the viscera…this demands a radical shift in our therapeutic assumptions,” he asserts. The trauma-immune connection is one of many reasons to address the importance of psychological health as a cornerstone of medical care. By understanding how the body “keeps score” of our experiences, we can work toward therapies that address trauma at its roots. Offering survivors not just relief, but the possibility of true recovery can bridge the gap between mental and physical health.