Post-traumatic stress disorder (PTSD) was first introduced as a diagnosis in 1980 and can be defined as a traumatic event that occurs when a person experienced, witnessed or was confronted with an event or events that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others. The response to this involved intense fear, helplessness or horror.
Psychoneuroimmunology (PNI) is the study of relationships between the nervous, endocrine and immune systems, previously considered to operate in isolation to each other.
PNI studies identify direct relationships between stress and immunosuppression. Psychological stressors such as bereavement and tertiary exams can reduce immune responses and render an individual more susceptible to disease and ill health. Physiological stress such as extreme temperatures or viruses can also reduce the ability to fight disease.
PNI identifies three pathways in response to stress.
- The sympathetic-adrenal-medullary pathway (SAM) is activated via the sympathetic nervous system by short term, acute stress. This is an innate response that supports survival in a life-threatening situation.
- The hypothalamic-pituitary-adrenal (HPA) axis is a slower response to provide resistance and protection from more long-term stress. Long term stress can dysregulate levels of the stress hormones, cortisol and adrenaline which ultimate leads to exhaustion.
- The inflammatory response reacts differently to short versus long term stress. In acute stress, the immune systems chemical messengers, cytokines increase inflammation to help fight and heal infection. In severe or overwhelming stress, regulation of cytokines is often impaired.
Since immune alterations are apparent in patients with PTSD and the stress response influences immune function, PNI offers a useful framework to study links between PTSD, immunity, disease and psychological dysfunction. Traumatic events increase pro-inflammatory cytokine activity and it is understood that elevated levels of these cytokines are linked to inflammation, depression, sleep disorders, coronary heart disease, impaired wound healing and chronic pain.
Therefore, treatments that encourage down-regulation of the stress response can modify inflammatory responses and thereby improve psychological and physical health in people who have experienced trauma.
Relaxation therapies such as deep breathing, guided imagery and progressive muscle relaxation inhibit the sympathetic nervous response, down regulate stress responses and reduce production of cortisol and adrenal. Strong research highlights benefits of these techniques for a range of conditions associated with PTSD, both psychological and physical.
While the public health budget is stretched to the limit and increasingly, people are ‘time poor’, simple relaxation techniques are cost efficient, require little time and can be practiced almost anywhere, anytime.