Most affected population

It is proven that some people are placed in higher risk for developing this disorder and those include:

1. Those who experience greater stressor magnitude and intensity, unpredictability, uncontrollability, sexual victimization, real or perceived responsibility, and betrayal
2. Those with prior vulnerability factors such as genetics, early age of onset and longer-lasting childhood trauma, lack of functional social support, and concurrent stressful life events
3. Those who report greater perceived threat or danger, suffering, upset, terror, and horror or fear
4. Those with a social environment that produces shame, guilt, stigmatization, or self-hatred
5. Those who have a history of alcohol and drug abuse
   

Pathophysiology of the PTSD
Several researches have came to the conclusion that PTSD may be associated with a number of distinctive neurobiological and physiological changes. Some of those are:

• altered brainwave activity,
• decreased volume of the hippocampus,
• abnormal activation of the amygdale

These brain structures are involved in the processing and integration of memory.
Physiological alterations associated with PTSD include:

• hyper-arousal of the sympathetic nervous system,
• increased sensitivity of the startle reflex,
• sleep abnormalities

There were also several researches on the subject of hormone imbalances! It was found that people with PTSD have abnormal levels of key hormones involved in the body's response to stress. The response to stress in PTSD is abnormal with long-term high levels of norepinephrine, at the same time as cortisol levels are low, a pattern associated with facilitated learning in animals. What happens during the stress? In reaction, body releases adrenaline, which is responsible for increasing blood pressure and heart rate and increasing glucose to muscles. What happens if the cortisol is low? Well, if body does not generate enough cortisol to shut down the flight or stress reaction, patient may continue to feel the stress effects of the adrenaline for a long time!

Co-occurring psychiatric disorders

PTSD is associated with the increased likelihood of co-occurring psychiatric disorders. Some of the most common co-occurring disorders are:

• alcohol abuse or dependence (51.9 percent),
• major depressive episodes (47.9 percent),
• conduct disorders (43.3 percent),
• drug abuse and dependence (34.5 percent)]