Childhood Trauma and Autoimmunity: An Interwoven Connection
Childhood Trauma and Autoimmunity
We are sensitive beings, especially to our environment. Our body responds to everything, even at the cellular level. We are born with a very immature immune system that slowly develops throughout childhood. This is so our body can adjust to the bacteria of many different environments to which we are exposed. Our immune system slowly develops as we are exposed to various pathogens and antigens. Stress increases circulating cytokines in the body, thus increasing inflammation. In this piece, we discuss the link that exists between childhood trauma and autoimmunity. During childhood, when we are exposed to severe stressors, this can influence the development of the immune system. This leads to higher levels of inflammation and inflammatory responses in adulthood, increasing the risk for autoimmune conditions. Stress-induced inflammatory responses may have implications for our future health.
Childhood Trauma Increases Inflammation
How are childhood trauma and autoimmunity related? The field of psychoneuroimmunology is growing, as more and more studies are finding links between our immune health (gut health) and brain health. Early maternal/infant separation reduces maternal caregiving when reunited. This increases stress reactivity in the infant, increasing pro-inflammatory cytokines in the blood, antigen-induced immunoproliferation in the spleen, and pro-inflammatory genes in the brain and gut microbes. These inflammatory markers impact our gut health, which increases our risk of autoimmune genes being switched on.
The role of cytokines:
Cytokines play a central role in immune health and inflammatory responses relating to childhood trauma. Cytokines coordinate cell to cell communication, alter neurochemical and neuroendocrine processes that have a huge impact on physiology and behavior. Cytokines are thought to function in a manner similar to neurotransmitters and hormones. They mediate physiological responses in the body. Some cytokines coordinate cell functions related to inflammation, those that increase or up-regulate inflammation are referred to as pro-inflammatory, whereas those that down-regulate inflammation are called anti-inflammatory. When a child is under extreme stress, this increases pro-inflammatory cytokines circulating in the blood. Another protein that plays a major role are lipopolysaccharide binding proteins.
The role of lipopolysaccharide binding proteins:
Lipopolysaccharide binding proteins (important components to our innate immune system) are dramatically decreased in the hippocampus when exposed to early life stressors and childhood trauma.
Low Lipopolysaccharide levels are associated with:
- impaired hippocampal-dependent memory
- increased anxiety-like behaviors
- increased spine density and abnormal spine morphology
These findings suggest that early life stressors can negatively impact our adult brain health, and increase our risk for developing PTSD, anxiety, and other mental health issues.
The Effects of Childhood Trauma Can Be Detected In The Blood
Many studies are now showing a direct link between childhood trauma/abuse and increased inflammatory markers in the blood. The association between abuse and neglect and inflammation can already be detected in blood during the childhood years. Researchers tested adolescent children who experienced maltreatment during childhood. They found high inflammation biomarkers in the blood of the mistreated children, compared to the control.
‘We found that children experiencing maltreatment and depression showed significantly elevated inflammation levels, regardless of their socioeconomic status, gender, zygosity, body temperature and waist-hip ratio. These findings are consistent with studies reviewed elsewhere, suggesting that depressed + maltreated adults have enduring intertwined abnormalities in the brain, endocrine, and immune functioning.’ -source
The Progression of Autoimmunity
We all have certain genes that can be altered depending upon a multitude of environmental factors. Some of these genetic ‘switches’ (because they can be turned on or off depending on our environment) are related to autoimmunity. There are a variety of theories as to the mechanism of how childhood trauma impacts adult autoimmunity.
- Childhood trauma may elicit acute inflammatory responses through stimulation of the sympathetic nervous system.
- Physical injury and infections can trigger innate immunity and increase inflammation.
- Activation of inflammatory responses during brain formation in early life can affect the brain development and neuroendocrine reactivity.
- Childhood trauma has been associated with adult hypothalamic-pituitary-adrenal (HPA) axis dysfunction. This 3 legged stool, the HPA, impacts hormones, cortisol, thyroid functioning.
- Early life trauma impacts the gut microbiome, and we know the microbiome plays a big role in autoimmunity. ‘Stress hormones can affect bacterial growth and compromise the integrity of the intestinal lining, which can result in bacteria and toxins entering the bloodstream. This can cause inflammation.’ This can impact brain health and contribute to PTSD and mental health issues later in life.
Less Childhood Stress=Stronger Immune Health
As you can see there is a multitude of factors at play here when it comes to childhood trauma and autoimmunity, many of which I barely touched upon, and even more yet to be discovered. However, stress plays a major role in maintaining our health, and research is showing that childhood trauma can impact physical and emotional health for years to come. It’s important to make this realization so we can work to alter our genes back to a healthier state (yes this is possible, more to come)!