Post-traumatic stress disorder, or PTSD, is an anxiety-related mental health condition that arises after an individual experiences a life-threatening, traumatic event. Although medical professionals may classify PTSD as mild, moderate, or severe, the diagnostic criteria for the disorder is the same. Mild PTSD, as an official diagnosis, is not recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM) or the International Classification of Diseases (ICD.) Rather, mild PTSD is a subjective assessment that indicates an individual who suffers from PTSD has mild symptoms compared to moderate or severe cases.
Not every traumatic event will trigger a stress disorder. Likewise, not every individual is subject to developing PTSD, even if several individuals experience the same event. Some events, such as violent crimes, war, natural disasters, or abuse, are more likely to cause PTSD, although one individual may develop a mild case, while another develops a severe case of PTSD. Little is known regarding why some individuals develop PTSD and others do not, although already-present anxiety disorders can contribute to the severity of the disorder.
![](http://images.wisegeek.com/slideshow-mobile-small/man-in-thought.jpg)
Whether a person is diagnosed with severe, moderate, or mild PTSD depends on the severity with which various symptoms present. In order for medical professionals to diagnose PTSD, a patient must present with symptoms of marked anxiety in four categories. The four primary categories of symptoms include reliving or intrusion, avoidance, numbing, and arousal. Different patients will have symptoms from all four categories in varying degrees, with some individuals experiencing additional symptoms. Experiencing further symptoms, such as hallucinations, aggressive behavior, or ringing in the ears, is less common for individuals with mild PTSD.
![](http://images.wisegeek.com/slideshow-mobile-small/soldier-with-hand-to-his-head.jpg)
Reliving the incident is a primary symptom and involves persistent, intrusive memories or thoughts about the incident, including nightmares. With avoidance, individuals become unusually fearful of people, places and things associated with the event, and will often avoid any exposure to such triggers. Numbing is similar to avoidance, with the exception that the individual creates an abnormal emotional distance from people or activities, whether related to the traumatic event or not. Finally, arousal is the fourth category of symptoms, typically presenting as hypervigilance, lack of concentration, or sleepless nights.
![](http://images.wisegeek.com/slideshow-mobile-small/soldier-in-uniform-covering-his-face-with-his-hands.jpg)
Typically, if symptoms are disruptive to the individual, but not debilitating, the individual is classified as having mild PTSD. Debilitating depression, suicidal thoughts, fear, panic attacks, aggressive outbursts, and similar behaviors often indicate more severe PTSD. Treatment for the condition involves several approaches, often based on the severity of symptoms and the effect such symptoms have on the individual's ability to function. Psychotherapy and medications are the most common course of treatment for mild to moderate PTSD.