In the video below Dr. Frank Ochberg, an expert on traumatic stress explains both Chronic PTSD and Complex PTSD. He also discusses the differences between them.
Video is courtesy of the Gift From Within YouTube channel
What is Complex PTSD?
Complex PTSD, is the result of multiple traumatic events occurring over a period of time, often referred to as “complex trauma”. Causes include multiple incidents of child abuse, particularly child physical abuse and child sexual abuse, prolonged domestic violence, concentration camp experiences, torture, slavery, and genocide campaigns. Complex Post-traumatic Stress Disorder is not a diagnosis in the DSM-5 psychiatric manual, released in 2013, but is planned for inclusion in the ICD-11 diagnostic manual, due for release in 2017. 
Complex PTSD Symptoms
- Interpersonal problems includes social and interpersonal avoidance (avoiding relationships), feeling distance or cut off from others, and never feeling close to another person.
- Negative self-concept involves feelings of worthlessness and guilt. While survivors of PTSD may feel “not myself”, a survivor of Complex PTSD may feel no sense of self at all or experience a changed personality; a few may feel as if they are no longer human at all (Lovelace and McGrady, 1980; Timerman, 1981).:385-386. Believing yourself to be “contaminated, guilty, and evil” is commonly reported by survivors of Complex PTSD. A fragmented identity is common, with Dissociative Identity Disorder occurring in some people. :386
- Interpersonal sensitivity includes having feelings which are easily hurt, anger/temper outbursts and difficulties with interpersonal relationships. Complex PTSD is normally the result of interpersonal trauma, the long duration of the trauma and the control of the perpetrator(s) prevents people from expressing anger or rage at the perpetrator(s) during the trauma; anger and rage both at perpetrators and the self can only be fully expressed after the trauma ends. Prolonged abuse normally leads to a loss of previously-held beliefs, with feelings of “being forsaken by both man and God”. :382,386
- Affect dysregulation means being unable to manage your own emotions, and is often referred to as “difficulties with emotional regulation”. The unexpressed anger and internalized rage resulting from the trauma may lead to self-destructive or reckless/risk taking behaviors, e.g., self-harm and/or suicide attempts, which may be driven by a sense of self-hatred. :382, 
- People with Complex PTSD also meet the diagnostic criteria for PTSD, which are:
- a persistent sense of threat, e.g. hypervigilance and being easily startled
- avoiding reminders of the traumas,
- and re-experiencing or reliving the traumas, for example flashbacks and intrusive thoughts about the trauma.
In addition to the symptoms above, survivors of prolonged child abuse have an increased risk of both self-injury and repeated victimization, for example relationships with abusive people, sexual harassment, and rape. :387
Judith Lewis-Herman, who first proposed Complex PTSD as a separate diagnosis, stated:
Observers who have never experienced prolonged terror, and who have no understanding of coercive methods of control, often presume that they would show greater psychological resistance than the victim in similar circumstances. The survivor’s difficulties are all too easily attributed to underlying character problems, even when the trauma is known. When the trauma is kept secret, as is frequently the case in sexual and domestic violence, the survivor’s symptoms and behavior may appear quite baffling, not only to lay people but also to mental health professionals. The clinical picture of a person who has been reduced to elemental concerns of survival is still frequently mistaken for a portrait of the survivor’s underlying character.” :388
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