Prevalence, Symptomolgy and Etiology of PTSD

Symptoms of PTSD At least 30 days of the following symptoms: Affective: anhedonia, emotional numbing and withdrawal, depression Behavioral: hypervigilance, passivity, nightmares, impulsivity, substance abuse, inability to work, marital problems Cognitive: intrusive memories, inability to concentrate, hyperarousal, flashbacks/nightmares Somatic: headaches, body aches, insomnia, digestion issues, loss of developmental skills (in kids)

PTSD: Prevalence 1-3% of all Americans 5% chance of PTSD in lifetime in men 10% chance of PTSD in lifetime in women Symptoms have been observed around the world Davidson (2007) and Breslau (1998) Estimate 15-24% of people who experience traumatic events will have PTSD

Factors influencing Prevalence Type of Trauma 3% physical attack 20% wounded in combat 1988: est. 15.2% of all Vietnam Vets had PTSD, and 30% had had it at sometime after the war 33% loss of a loved one 50% rape victims Community exposure to trauma NY after 9-11 showed elevated rates of PTSD related to proximity to ground zero See also: Rwanda, Northern Ireland

Biological Causes Role of Noradrenalin: increased levels = more open expression of emotion Geracioti (2001): PTSD subjects had higher NorAd levels than non-PTSD subjects; adrenal stimulation = panic attacks (70%) and flashbacks (40%) vs. 0% in both controls Bremner (1998): PTSD subjects had increased sensitivity of Norad receptors

As cortisol levels decrease, norepinephrine levels increase resulting in an inability to regulate and recover from fight/flight responses

Brain Areas Affected by PTSD

Genetic Implications Kolassa (2010): Val158Met polymorphism, gene for encoding the enzyme catechol-O-methyltransferase (COMT) levels affect Norad and Dopamine release during stress Helps explain how two people can experience the same trauma and not both show symptoms of PTSD

Cognitive causes Thoughts of “lack of control” suggest external locus of control and survivor guilt Intrusive/pervasive thoughts come from “cue dependent memory” (Berwin et al 1996) Rizzo: flooding therapy, “virtual Iraq” aided coping, recovery and “Habituation” (gradual fading of stress reactions)

Internal locus of control reduces PTSD; External LOC increases PTSD Sutker et al (1995): soldiers with purpose/commitment to military/mission have lower rates of PTSD (Internal) Can be linked to attributional style and Beck’s “cognitive schema” ideas on depression (Internal) Suedfeld (2003): Holocaust survivors with external LOC more likely than controls to experience PTSD and also show low trust and a skeptical world view http://www.youtube.com/watch?v=M5UE69o99lo

Sociocultural causes Suggests racism/prejudice/oppression are predisposing factors Roysircar (2000): meta analysis showed ethnic differences in PTSD rates for Vietnam vets; black 20.6%, Hispanic 27.6%, white 13% Dyregov: Rwandan kids: threatened with death #1 cause of intrusive thoughts and withdrawal behavior Bosnian research 1998: 73% of girls (higher due to additional threat of rape, Kaminer et al 2000), 35% of boys from Sarajevo showed PTSD

Somatic symptoms of PTSD commonly treated across all cultures Body Memory Symptoms: non-western, physical ailments solely from psychological causes (see Somatoform disorders)

Gender Considerations Horowitz et al (1995): risk is 5x greater for women than men Breslau et al (1991): 1007 kids exposed to violence PTSD rates: 11.3% in girls, 6% in boys Different symptoms: Men show irritability, impulsiveness and aggression, substance abuse (external symptoms); women show numbing, withdrawal and avoidance/anxiety (internal symptoms) http://www.youtube.com/watch?v=rYc7Ey-kO-0