Muito além do trauma: uma investigação sobre o papel das reações peritraumáticas sobre o transtorno de estresse pós-traumático

Abstract

Posttraumatic stress disorder (PTSD) is a debilitating condition that greatly impacts quality of life. Among several PTSD risk factors, peritraumatic reactions (PR) such as peritraumatic tonic immobility (PTI), dissociation (PD) and physical panic reactions (PPR) are some of the most investigated. However, several studies have assessed these PR separately, and the pathway connecting them to PTSD is not well understood. Therefore, this thesis aimed to: (i) simultaneously estimate the effect of the three PR on PTSD using a validated instrument; and (ii) assess if there is an indirect effect of PTI on PTSD mediated by feelings of guilt/shame. We used structural equation modelling to analyse data from 3211 participants from Rio de Janeiro and São Paulo. We treated the PR as latent variables and selected specific confounders for each reaction. Our exposures were the PR, and PTSD was the outcome. We calculated odds ratios and 95% confidence intervals for each analysis. We also employed the Bayesian Information Criterion to compare the goodness of fit between non-nested models. Separately, all PR achieved statistically significant results. However, only PD (ORPD=1.8; 95%CI:1.3-2.4) and PPR (ORPPR=2.5; 95%CI:1.8-3.4) remained statistically significant when all three were included in a model with their respective confounders and correlations among all PR. Our findings suggested a possible effect of PTI on PTSD (ORPTI=1.4; 95%CI:1.0-1.9). Interactions between the PR were not statistically significant. When we investigated feelings of guilt/shame as the mediator between PTI and PTSD, the indirect effect achieved a borderline statistical significance (ORPTI(TNIE)=1.1; 95%CI:1.0-1.2). Direct (ORPTI(PNDE)=1.3; 95%CI:0.8-1.8) and total (ORPTI(TE)=1.4; 95%CI:0.9-1.9) effects lost their significance when all PR, their confounders and correlations were included in the same model. The other PR remained statistically significant (ORPD=1.7; 95%CI:1.3-2.3 and ORPPR=2.5; 95%CI:1.8-3.4). Our findings showed PD and PPR to increase the risk of PTSD even when considered in tandem. PTI could have an effect on PTSD, but this must be considered cautiously, as this PR only reached borderline significance in our final model. Feelings of guilt/shame did not significantly mediate PTI’s effect on PTSD. However, a borderline statistical significance in the indirect effects warrants further investigation. Our findings reinforce the hypothesis that peritraumatic reactions should be analysed and understood as simultaneous occurrences, not as separate entities. It would also be appropriate for studies concerning guilt/shame, PTI and PTSD to focus on traumas characterized by imprisonment and feelings of inescapability, given that these experiences are allegedly more likely to trigger PTI.