The posttraumatic stress disorder project in Brazil: neuropsychological, structural and molecular neuroimaging studies in victims of urban violence

Abstract

Background: Life trauma is highly prevalent in the general population and posttraumatic stress disorder is among the most prevalent psychiatric consequences of trauma exposure. Brazil has a unique environment to conduct translational research about psychological trauma and posttraumatic stress disorder, since urban violence became a Brazilian phenomenon, being particularly related to the rapid population growth of its cities. This research involves three casecontrol studies: a neuropsychological, a structural neuroimaging and a molecular neuroimaging study, each focusing on different objectives but providing complementary information. First, it aims to examine cognitive functioning of PTSD subjects and its relationships with symptomatology. The second objective is to evaluate neurostructural integrity of orbitofrontal cortex and hippocampus in PTSD subjects. The third aim is to evaluate if patients with PTSD have decreased dopamine transporter density in the basal ganglia as compared to resilient controls subjects. This paper shows the research rationale and design for these three case-control studies.

Candidate-Gene Approach in Posttraumatic Stress Disorder After Urban Violence: Association Analysis of the Genes Encoding Serotonin Transporter, Dopamine Transporter, and BDNF

“…Other studies have already suggested that dopamine plays an important role in the pathogenesis of PTSD (Comings et al 1996;Segman et al 2002;Bressan et al 2009). …”

Executive function and PTSD: Disengaging from trauma

“…Other measures requiring inhibition of responses include the go-nogo, stop-signal, and attention network (ANT) tasks (Logan, 1994; Shucard , et al 2008; Jenkins , et al 2000; Fan , et al 2002). Decreased inhibitory function has rather consistently been reported for PTSD (Falconer , et al 2008; Wu , et al 2010; Koso and Hansen 2006; Casada and Roache 2005; Shucard , et al 2008; Bressan , et al 2009; Jenkins , et al 2000; Leskin and White 2007), and performance has been reported to relate to PTSD symptom severity (Falconer , et al 2008; Leskin and White 2007). The color-word Stroop task (Stroop, 1935; Delis , et al 2001) examines response time to name the ink color of a color-related word (e.g., “red” printed in blue ink) and is also thought to be a measure of inhibitory function.…”

The Impact of Epidemic Violence on the Prevalence of Psychiatric Disorders in Sao Paulo and Rio de Janeiro, Brazil

“…Due to an expected refusal rate of 20%, and in order to increase the likelihood of identifying post-traumatic stress disorder cases, the three strata with the highest homicide rates were oversampled, resulting in 1500 interviews. In Sao Paulo, we expected to identify approximately 120 current cases to be referred to a case-control study [23] and to a clinical trial [24] on post-traumatic stress disorder (PTSD). As we expected a 5% one-year prevalence of PTSD, we decided to increase the sample size to 3,000 interviews to allow for the identification of the required PTSD cases.…”