Post-traumatic stress disorder can be caused from exposure to trauma, such as:

• Car accident

• Sexual assault

• Natural disaster

• Experiences in war

The U.S. Department of Veterans Affairs points to some key indicators:

• Nightmares about what happened or thinking about the incident when you don’t want to.

• Going out of your way to avoid situations that remind you of the past experience.

• Hypervigilance, or constantly on guard, watchful or easily startled.

• Feeling numb or detached from what’s happeneing around you, other people and activities.

The VA says if anyone answers yes to any three, it recommends that person see a doctor for an assessment.

Additional symptoms may include

• Irritability

• Problems concentrating

• Fatigue or feeling worn out

• Headaches

• Chronic body pain

• Emotional upset

Other PTSD facts

It has been called soldier’s heart, shell shock, combat neurosis or battle fatigue.

Experts say symptoms may not appear for months or years once one has been exposed to a traumatic event.

Substance abuse, difficulty on the job or in school and relationship conflicts may arise, too, according to the VA.