Post-traumatic stress disorder (PTSD) is an anxiety disorder that can develop after exposure to a terrifying event or ordeal in which grave physical harm occurred or was threatened. According to the National Center for PTSD, about 7 to 8 percent of the United States population will have PTSD at some point in their lives and about 5.2 million adults have PTSD during a given year. Traumatic events that may trigger PTSD include violent personal assaults, natural or human-caused disasters, accidents, or military combat.
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