ارزیابی شناختی ناکارآمد و واکنش پذیری روانشناختی در اختلال استرس حاد

Abstract The present study investigated the extent of dysfunctional appraisal as measured with the Posttraumatic Cognitions Inventory (PTCI) and physiological responses to trauma-related material in patients with acute stress disorder (ASD; N = 44) in comparison to participants without trauma exposure (N = 27). Heart-rate (HR), skin conductance responses (SCR), and viewing time were recorded in response to – for trauma victims – idiosyncratically trauma-relevant and control pictures. ASD patients evidenced greater dysfunctional appraisal than control participants with regard to the PTCI scales Self and World and also an accelerative HR reaction and greater SCRs to trauma-relevant pictures. Among patients, PTCI was highly correlated with ASD severity while PTCI World was positively correlated with resting HR and depression. Amplitude of the HR reaction to trauma-related pictures was negatively correlated with viewing time. Results suggest that dysfunctional appraisal and autonomic reactivity are only loosely related in ASD.

Introduction Acute stress disorder (ASD) is an acute trauma response characterized by dissociative, reexperiencing, avoidance, and hyperarousal symptoms (American Psychiatric Association, 2000) that are predictive of posttraumatic stress disorder (PTSD; Bryant et al., 2003 and Elsesser et al., 2005). Presence of some of the ASD symptoms has been well supported by empirical evidence, such as hyperarousal reactions to cues that are reminders of the trauma (e.g., Elsesser, Sartory, & Tackenberg, 2004). Others have been more controversial or fail to be listed at all such as dysfunctional cognitive appraisal of the trauma and its sequelae, although they too have been found to be predictive of PTSD (Ehring et al., 2008 and Kleim et al., 2007). One reason for the controversy might be due to the methodology of the studies of cognitive appraisal in ASD. In most cases, recent trauma victims with ASD were compared with those without ASD. Comparing groups differing – in some cases – only slightly in symptom severity could have obscured the presence of dysfunctional cognitions in ASD. In the present study, recent trauma victims with ASD were compared to participants without trauma exposure to confirm the presence of dysfunctional appraisal in ASD. The Posttraumatic Cognitions Inventory (PTCI; Foa, Ehlers, Clark, Tolin, & Orsillo, 1999) is a frequently employed measure of dysfunctional cognitions. It consists of three subscales: namely, negative cognitions about Self, about the World, and Self-blame. Negative cognitions about Self assesses the sense of negative change in the self, of alienation, hopelessness, general mistrust and the negative interpretation of symptoms (e.g., “There is something wrong with me as a person”). Negative cognitions about the World assesses mistrust of other people and a sense that the world is a dangerous place (e.g., “You can never know who or what will harm you”) while the Self-blame subscale assesses blame for the traumatic incident itself (e.g., “The event happened because of the way I acted”). The PTCI discriminated well between traumatized individuals with and without PTSD (Foa et al., 1999) and its three-factor structure has been supported in a confirmatory analysis (Beck et al., 2004). Elsesser and Sartory (2007) found significantly increased negative appraisal with regard to the subscale World in recent trauma victims compared to controls not exposed to a traumatic event. A comparison group of chronic PTSD patients gave higher ratings than controls and recent trauma victims with regard to the subscales World and Self. In recent trauma victims, negative appraisal increased with days since the traumatic event suggesting a progressive development of dysfunctional appraisal together with other symptoms of PTSD. However, only half of the trauma victims met ASD criteria in the previous study (Elsesser & Sartory, 2007), which may have accounted for their similarity with non-exposed controls regarding the appraisal of Self and Self-blame. In the present study, all of the recent trauma victims were affected by ASD (excepting criterion B). They were compared with non-exposed controls to assess the presence of early dysfunctional cognitions following a traumatic event. Another inquiry concerned the relationship between cognitive factors and other criterion variables in the ASD group. Enhanced physiological reactivity to trauma cues has been shown to be a robust correlate of PTSD. A recent meta-analysis revealed mean weighted effect sizes that were significant with even the most conservative tests (Pole, 2007). There are fewer studies in recent trauma victims. In the first, motor vehicle accident (MVA) victims with or without symptoms of PTSD were presented with idiosyncratic accounts of their accident 1–4 months after the incident (Blanchard, Hickling, Taylor, Loos, & Geradi, 1994). In this study, as in a replication (Blanchard et al., 1996), an increase in HR to the idiosyncratic account was the best discriminator between symptomatic and non-symptomatic groups. Nixon, Bryant, Moulds, Felmingham, and Mastrodomenico (2005) also reported an increased HR response during trauma narratives in acute trauma victims. Employing idiosyncratic pictures of the reported traumatic incident, Elsesser et al. (2004) found an increased evoked HR reaction in acute trauma victims with ASD. In this study HR amplitude was positively correlated with ASD severity notably, reexperiencing. A further assessment 3 months later (Elsesser et al., 2005) revealed a significant correlation between the initial increase in HR to trauma-related pictures and subsequent PTSD severity. As both dysfunctional appraisal and physiological reaction were shown to be predictive of the development of PTSD, it was of interest to find out whether or not the two were related. Finally, individuals with ASD report a higher degree of avoidance than trauma victims without ASD (Elsesser et al., 2004). There are hardly any studies using behavioral avoidance measures in ASD. Elsesser et al. (2004) presented trauma-related and control pictures to recent trauma victims, PTSD patients and healthy controls. Subjects could terminate the display themselves and viewing time was recorded. Unexpectedly, PTSD patients and recent trauma victims viewed the idiosyncratically trauma-related pictures for a longer time than controls or other pictures. Repeated exposure could have accounted for the failure to find evidence of avoidance in this previous study as participants were seeing the pictures for the forth time and may have habituated to their fear-arousing properties. The picture stimuli were presented only twice in the present study. In the present study, recent trauma victims with ASD and unexposed controls were compared to dysfunctional cognitive appraisal, as measured with the PTCI, evoked HR, and SCR to idiosyncratically trauma-related and control pictures, as well as viewing time of pictures as a measure of avoidance. In keeping with some of the previous results, ASD patients were expected to exhibit a higher level of dysfunctional appraisal, enhanced psychophysiological reactivity and greater avoidance than unexposed controls. Finally, dysfunctional cognitive appraisal and physiological reactivity were expected to be related in ASD participants.

. Results Healthy controls and ASD patients did not differ significantly in terms of age, years of education or sex ratio (Table 1). Table 1. Group means and (standard deviations) of clinical variables and questionnaire scores. Variable ASD group (N = 44) Control group (N = 27) Sex (m/f) 14/30 10/17 Variable ASD group (N = 44) Control group (N = 27) M SD M SD Age 38.30 12.12 40.63 8.82 Years of education 10.34 1.93 10.8 1.89 ASDI Dissociation 2.59 1.50 Reexperiencing 2.7 .82 Avoidance 2.68 1.12 Hyperarousal 4.25 1.38 ASD-total (0–19) 12.23 3.32 IES-R Intrusion 22.95 6.86 Avoidance 19.36 9.43 Hyperarousal 22.09 8.28 Questionnaires Peritraumatic Dissociation 1.95 2.58 Posttraumatic Dissociation .98 .84 PTCIa Selfb 2.54 1.20 1.83 .78 Worldb 4.09 1.26 3.14 1.37 Self-blame 2.63 1.46 2.37 1.49 Total scoreb 94.65 35.44 68.25 30.28 STAI Stateb 49.00 11.61 35.30 10.83 STAI Traitb 41.80 8.79 37.33 9.73 Depression (BDI)b 12.43 9.16 6.93 7.25 ASD: acute stress disorder; ASDI: Acute Stress Disorder Interview; BDI: Beck Depression Inventory; PTCI: Posttraumatic Cognition Inventory; IES-R: Impact of Event Scale-Revised. a Control subjects (N = 24) rated the PTCI with regard to their most stressful experience. b Significant group differences. Table options 3.1. Questionnaires Group means of questionnaire data are shown in Table 1. Three control and one ASD subjects failed to complete the PTCI. ANOVAs revealed significantly higher scores for the ASD compared to the control group with regard to total score of the PTCI, F(1, 66) = 9.45, p ≤ .01, η2 = .13; negative appraisal of Self, F(1, 66) = 6.92, p ≤ .02, η2 = .10; and the World, F(1, 66) = 8.21, p ≤ .01, η2 = .11. The ASD group exhibited also higher scores with regard to STAI state anxiety, F(1, 70) = 24.52 and p ≤ .001, η2 = .26; BDI depression, F(1, 70) = 7.04, p ≤ .01, η2 = .09. 3.2. Appraisal of picture material Appraisal data are missing from one subject in both groups. Mean ratings of trauma-relevance, valence and arousal were entered into a 2 × 4 mixed design ANOVA comparing groups and type of picture (neutral, generally aversive, trauma-relevant and pleasant). Unlike control subjects, ASD patients rated the trauma-related pictures as being more relevant to their trauma than other pictures: group × type of picture, Wilk's Lambda F(3, 65) = 49.32, p ≤ .001, η2 = .70 ( Fig. 1a). There were also significant group × type of picture effects for valence, Wilk's Lambda F(3, 65) = 7.28, p ≤ .001, η2 = .25 ( Fig. 1b) and arousal ratings, Wilk's Lambda F(3, 65) = 13.94, p ≤ .001, η2 = .39 ( Fig. 1c). Unlike ASD patients, controls rated generally aversive pictures as being more unpleasant and arousing than trauma-related pictures. Furthermore, ASD patients rated trauma-relevant pictures as being more unpleasant and arousing than the control group (all ps ≤ .05) whereas control subjects rated generally aversive pictures as marginally more unpleasant than ASD patients. Groups did not differ in their ratings of other types of pictures. Group means of ratings of trauma relevance (a), valence (b), and arousal (c) of ... Fig. 1. Group means of ratings of trauma relevance (a), valence (b), and arousal (c) of idiosyncratically trauma-related, generally aversive, idiosyncratically pleasant and neutral pictures in ASD patients and controls. Figure options 3.3. Psychophysiological measures HR. Resting HR was submitted to a group comparison. There was no significant group effect ( Table 2). Table 2. Group means and (standard deviations) of psychophysiological variables. Variable ASD group Control group M SD M SD Resting levels RestHR 70.34 9.08 69.43 9.47 SF 12.50 5.79 13.89 8.15 SCL (log μS) .88 .51 .69 .46 HRR amplitude HRR trauma 5th s 1.78 3.65 −.63 3.06 ASD: acute stress disorder; RestHR: tonic heart-rate during resting period; SF: number of spontaneous fluctuations recorded during resting period; SCL: Scin conductance level; HRR trauma 5th s: HR amplitude 5th second response evoked by trauma-relevant pictures. Table options HR responses to pictures are shown in Fig. 2. Data were entered into analysis of variance comparing group (2) × type of picture (4) × second (6). There were significant main effects for second, Wilk's Lambda F(5, 65) = 3.67, p ≤ .01, η2 = .22 and type of picture, Wilk's Lambda F(3, 67) = 4.93, p ≤. 01, η2 = .18. There were also significant interaction effects for type of picture × second, Wilk's Lambda F(15, 55) = 2.25, p ≤ .02, η2 = .38. Group differences were examined with regard to the separate picture types. Analyses revealed a significant group × second interaction in case of the trauma-relevant pictures only, Wilk's Lambda F(5, 65) = 3.30, p ≤. 01, η2 = .20. ASD patients showed an accelerative HR response during presentation of trauma-relevant material whereas control subjects showed a decelerative HR ( Fig. 2). There were no significant group × second effects with regard to the neutral, pleasant and the aversive pictures. In order to compare groups with regard to amplitude of the HR reactions, mean HR of second 5 was again submitted to ANOVA. There was a significant group effect only in case of the trauma-related pictures, F(1, 69) = 8.16, p ≤ .01, η2 = .11, but no significant group differences in regard to HR during presentation of neutral, aversive and pleasant pictures. Group means of the evoked HR reaction to generally aversive, neutral, and ... Fig. 2. Group means of the evoked HR reaction to generally aversive, neutral, and idiosyncratically trauma-related and pleasant pictures in ASD patients and controls. Figure options Skin conductance. Mean pre-stimulus SCL during presentation of pictures was log transformed to normalize the distribution. Spontaneous fluctuations during the resting phase and pre-stimulus SCL were submitted to a group comparison. There were no significant effects ( Table 2). SCR amplitude during picture presentation was transformed by square root to normalize the skewed distribution and entered into analysis of variance comparing group (2) × type of picture (4). There was a significant effect for type of picture, Wilk's Lambda F(3, 67) = 10.17, p ≤ .001, η2 = .31 and for group × type of picture, Wilk's Lambda F(3, 67) = 5.28, p ≤ .01, η2 = .19 ( Fig. 3). Post-hoc analyzes revealed significantly higher SCR amplitudes to trauma-related and generally aversive than neutral and pleasant pictures (ps < .01) and a significantly higher SCR amplitude in ASD than control participants to the trauma-relevant pictures, F(1, 69) = 8.12, p ≤ .01, η2 = .10. Group means of SCR to idiosyncratically trauma-related, generally aversive, ... Fig. 3. Group means of SCR to idiosyncratically trauma-related, generally aversive, idiosyncratically pleasant and neutral pictures in ASD patients and controls. Figure options 3.4. Viewing time (VT) Only VTs between 500 and 12,500 ms were included. The mean percentage of eliminated outliers was 3.56% (control group: 2.67%; ASD group: 4.13%). Owing to equipment malfunction, viewing time data of one ASD patient and of one control participant were missing. Mean VT was calculated for each picture type and log transformed to normalise data before submitting them to ANOVA comparing group (2) by type of picture (4). There were no significant group effects but a significant picture-type effect, Wilk's Lambda F(3, 65) = 90.62, p ≤ .001, η2 = .81, due to pleasant pictures being viewed longer than other picture material ( Fig. 4) and group × picture type effect, Wilk's Lambda F(3, 65) = 4.72, p ≤ .01, η2 = .18. Simple contrasts between type of pictures yielded significant group × type of picture effects for neutral and aversive pictures, F(1, 67) = 10.97, p ≤ .001, η2 = .14, and for neutral and trauma-relevant pictures, F(1, 67) = 5.62, p ≤ .03, η2 = .08, indicating a shorter viewing time of neutral than aversive and trauma-relevant material in the control but not in the ASD group. Group means of viewing time of idiosyncratically trauma-related, generally ... Fig. 4. Group means of viewing time of idiosyncratically trauma-related, generally aversive, idiosyncratically pleasant and neutral pictures in ASD patients and controls. Figure options 3.5. ASD patients: relations between measures Number of ASD symptoms, days since trauma, questionnaire scores and physiological reactions as well as viewing time were entered into correlational analyzes. PTCI. The total PTCI score was highly positively correlated with the total ASDI score, r(43) = .66, p ≤ .001, and the subscales Self and World, but not Self-blame, were similarly highly correlated with the sum of ASD symptoms. Furthermore, PTCI World was significantly and positively correlated with resting level of HR, r(42) = .38, p ≤ .05, and BDI depression, r(43) = .34, p ≤ .05. Furthermore, PTCI Self-blame was negatively correlated with HR reactions to trauma-relevant pictures, r(43) = −.34, p ≤ .05, indicating that more Self-blame is accompanied by a more marked orienting response to trauma-relevant material. Viewing time of trauma-related and generally aversive pictures was negatively correlated with number of ASD symptoms (VT trauma-related: r(43) = −.47, p ≤ .001; VT aversive: r(43) = −.37, p ≤ .05) and both measures of viewing time were also inversely related to self-reported avoidance behavior (IES-R Avoidance – VT trauma-related: r(43) = −.47, p ≤ .001; VT aversive: r(43) = −.36, p ≤ .05). Finally, HR reaction to the trauma-related pictures was also inversely related to viewing time of that material, r(43) = −.34, p ≤ .05 ( Fig. 5), indicating that the more marked the accelerative response the shorter the viewing time. Relationship between the evoked HR response (5th second) to and viewing time of ... Fig. 5. Relationship between the evoked HR response (5th second) to and viewing time of idiosyncratically trauma-related pictures (r = −.34) in ASD patients. Figure options None of the variables were significantly correlated with age of ASD patients.