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Posttraumatic Stress Disorder and the Rise of Chronic Diseases

I have worked in a prison for the last seven months. Nearly everyone who I have seen for clinic visits has reported some degree of trauma in their childhood. Studies corroborate this and show that 90% of juveniles committing crimes have a history of childhood trauma. The crucial and poignant message is that past trauma imprisons us in a cycle that impacts us throughout our lives.

Introduction: Childhood Trauma is Common

Our brains rely on the past as a reference point. Much of the brain’s processing is subconscious, as the brain rapidly assesses the environment, cues, and circumstances. That neurons fire 200 times per second is testimony to our decisions being made even before we realize them.

Humans have an innate survival instinct that calls upon the body to protect itself from direct or indirect threats. Stressors include interactions with others, the environment, and even situational stress conjured up by the brain itself. When stressors are ongoing or are moderately severe, they may leave an indelible impression on our brains and bodies – this is trauma. 

Traumatic events in childhood may influence the development of chronic diseases as adults. Unfortunately, physical and sexual abuse in children is common. A random sample of 10,000 Canadian residents showed a rate of child physical abuse of 31.2% and sexual abuse higher in females (12.8%) compared to males (4.3%) (MacMillan HL, 1997). A national US sample of 34,000 adults showed a prevalence of child sexual abuse of 10.14% (24.8% in men, and 75.2% in women) (Perez-Fuentes G, 2013).

Abuse sets up an adaptive cycle of fear aversion and repeated stress response. Trauma leads to a dysregulation of hormones and neurotransmitters, changes in the brain, and behaviors. Eventually, the behavioral adaptations of posttraumatic stress disorder (PTSD) can increase someone’s risk of developing a chronic disease. 

“The past is never dead. It’s not even past.”

—William Faulkner

Posttraumatic stress disorder (PTSD)

Being the witness to or victim of a trauma leads to feelings of insecurity, helplessness, and fear. Posttraumatic stress disorder (PTSD) either causes a person to have a heightened state of awareness and fear, or deactivation with numbness and withdrawal (Sherin, 2011). There is a dysregulation of the emotion and stress response systems in PTSD. Psychological trauma corresponds to changes in the brain that are similar to those seen in a traumatic brain injury (TBI). Imaging studies of patients with TBI or PTSD show impairments in the long axons to the prefrontal cortex – an area implicated in emotional regulation (Weis C, 2022).

The criteria for PTSD are listed in the table below.

Definition of PTSD: DSM-5 Criteria

  • Exposure to traumatic stressor – direct, indirect, or repeated
  • Recurrent, involuntary intrusive memories – traumatic nightmares, flashbacks, intensive or prolonged distress
  • Avoidance – avoiding places, conversations, people, or experiences that even remotely remind them of an experience, trauma-related thoughts/feelings, external reminders
  • Negative alterations in thinking and mood – inability to recall key events: persistent negative beliefs and expectations; persistent negative fears, horror, anger, guilt, shame; diminished interest in activities; constricted affect.
  • Alterations in arousal and reactivity – irritable and aggressive; self-destructive; hypervigilance; problems in concentration
  • Functional social or occupational impairment
  • Symptoms lasting longer than 30 days
  • Significant disruption in normal life pursuits

Biology of Posttraumatic Stress Disorder (PTSD)

Imagine walking on a trail in the woods and encountering a mountain lion. The brain coordinates an action: to confront the mountain lion, showing your dominance by making loud noises and stretching your body tall; staying still and waiting for it to leave; or running away and hoping that it cannot catch you. All of these responses are coordinated by the brain.

The biological changes of PTSD are endocrine, neurotransmitter, and anatomical.

Endocrine response 

A stressor is registered by the body as a threat. The innate pathway to prepare for an injury or threat to life is the fight-or-flight pathway (autonomic nervous system) regulated by the Hypothalamic-Pituitary-Adrenal (HPA) axis. Consider it the brain’s effort to protect the cells of the body from a risk of pain, injury, or death.

The brain’s coordinates this instinct to prepare the body to make an action toward or away from a noxious stimulus. The brain conducts the responses in the body by way of neurotransmitter production. Corticotropin releasing factor (CRF) from the hypothalamus leads to the production of adrenocorticotropin hormone (ACTH) from the pituitary. This hormone triggers the production of cortisol in the adrenal gland.

Cortisol affects the cells of various tissues leading to changes including an increased heart rate, dilated pupils, and the opening airways, shown in the infographic below. The brain adapts to an excess cortisol production by turning down the signal (CRF) to produce more. Interestingly, lower cortisol levels prior to a trauma may predispose to PTSD. 

Neurotransmitter changes

The principal neurotransmitters (NTs) in the stress response are the catecholamines epinephrine (adrenalin) and norepinephrine. The brain triggers the increase in these NTs as it faces a stressor, which directly affect the heart, lungs, and other organs. They ready the body for an acute response, with an increase in blood pressure and pulse, often referred to as “fight, flight, or freeze.” On the other hand, serotonin levels and Gamma-aminobutyric acid (GABA) levels are decreased, increasing awareness and memory effects.

Stress ties in with the body’s aversion to pain and attraction to pleasure. Cortisol increases dopamine production, leading to a motivation response and provoking a movement away from the pain and toward a pleasure. Studies support that dopamine dysregulation may play a crucial role in the development of behaviors such as drug addiction and chronic diseases. The stress becomes intertwined with coping strategies – such as exercise, meditation, a high-carb diet, sex, smoking, alcohol, and drug abuse.

Brain neuroplasticity

Hebb’s theory relates to how the brain strengthens its neurocircuitry when neurons are recruited – “if it fires, it wires.” After a significant stress response, the brain remodels, mainly in the hippocampus and the prefrontal cortex. Studies using Magnetic Resonance Imaging (MRI) show reduced volumes in these structures (Bremner J, 1999).

Where there is a structural change, there is a functional change. The hippocampus and prefrontal cortex are responsible for memory and emotional regulation.

The Impact of Posttraumatic Stress Disorder on Chronic Diseases: The ACEs Study

A past history of a significant traumatic event or chronic trauma can predict mental illness as well as a risk for chronic diseases.

In 1998, a pivotal study the ACEs study factored the influence of environmental exposure to trauma on the incidence of chronic diseases and mental health conditions.

Adverse Childhood Experiences (ACEs) are traumatic experiences that occur from birth to up to seventeen years of age. Examples of ACEs include physical abuse, sexual abuse, neglect, living with someone who abused drugs or alcohol, and losing a parent through divorce, death, or abandonment. Environmental risk factors include communities with few activities for young people, poverty, food insecurity, and easy access to drugs or alcohol in a community.

ACEs are common. In a 2014 UK retrospective study, almost 50% of the population had at least one ACE and 9% had 4 or more ACEs (Bellis, 2014). Those with 4+ ACEs had increased odds for smoking (4-fold), heavy drinking (3.7-fold), incarceration (9-fold), and morbid obesity (3-fold). The ACEs study reveals in its correlations a way to envision mental and physical illness as a behavioral adaptation to trauma.

posttraumatic stress disorder traps us into a behavior cycle of emotional and body dysregulation.
Photo by Engin Akyurt on Pexels.com

Posttraumatic Stress, Diabetes, and Obesity

In 67,853 women in the Nurses’ Health Study II, assessed for lifetime abuse from 1989 to 2005, child or teen physical abuse rates were 54%, and sexual abuse was 34% (Rich-Edwards, 2011). Moderate to severe physical and sexual abuse in childhood and adolescence was a risk factor to the development of diabetes as adults (hazards ratio (HR) of 1.26 for moderate physical abuse and 1.54 for severe physical abuse; 1.16 for unwanted sexual touching, 1.35 for forced sexual activity, and 1.69 for repeated forced sex) (Rich-Edwards, 2011).

A review of a similar population of women (n=54, 282) showed a correlation, in a dose-response manner, between symptoms of posttraumatic stress disorder (PTSD) and the likelihood of diabetes mellitus – with nearly a 2-fold increased risk (HR 1.8) of DM in women with the highest number of PTSD symptoms (Roberts, 2015).


Chronic diseases result from behaviors that lead to inflammation. About 6 in 10 US Americans have a chronic disease; 4 in 10 have two or more. As many as 75 to 90 percent of all clinical concerns are stress related. Posttraumatic stress disorder is an important instigator to behaviors that place a person at risk of chronic diseases. The article on how to fireproof your health centered on inflammation as the cause of chronic disease. Harmful behaviors take us to inflammation, and the root cause of these behaviors is trauma. A journey to optimal health benefits from a sensitivity to past traumas and posttraumatic stress disorder (PTSD).

PTSD leads to emotional and nervous system dysregulation, essentially locking a person into a behavioral cycle. Trauma-informed healthcare may offer strategies to address the root cause of a chronic disease and empower a patient to overcome the trauma that imprisons them.

We have learned that trauma is not just an event that took place sometime in the past; it is also the imprint left by that experience on mind, brain, and body. This imprint has ongoing consequences for how the human organism manages to survive in the present. Trauma results in a fundamental reorganization of the way the mind and brain manage perceptions. It changes not only how we think and what we think about, but also our very capacity to think.

Bessel A. van der Kolk


Bremner J. Alterations in brain structure and function associated with post-traumatic stress disorder. Semin Clin Neuropsychiatry. 1999; 4(4): 249-55.

MacMillan HL, et al. Prevalence of child physical and sexual abuse in the community. Results from the Ontario Health Supplement. JAMA. 1997; 278(2): 131-5.

Perez-Fuentes G, et al. Prevalence and Correlates of Child Sexual Abuse: A National Study. Compr Psychiatry. 2013; 54(1): 16-17.

Rich-Edwards J, Spiegelman D, et al. Abuse in Childhood and Adolescence as a Predictor of Type 2 Diabetes in Adult Women. Am J Prev Med. 2010; 39(6): 529-536.

Roberts A, Agnew-Blais J, et al. Posttraumatic Stress Disorder and Incidence of Type 2 Diabetes Mellitus in a Sample of Women. JAMA Psychiatry. 2015; 72(3): 203-210.

Sherin J. Post-traumatic stress disorder: the neurobiological impact of psychological trauma. Dialogues Clin Neurosci. 2011; 13(3): 263-278.

Weis C, et al. Emotion Dysregulation Following Trauma: Shared Neurocircuitry of Traumatic Brain Injury and Trauma-Related Psychiatric Disorders. Biological Psychiatry. 2022; Vol 91(5): 470-477.

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