Skip to main content
Download PDF

Modeling the structural relationships between trauma exposure with substance use tendency, depression symptoms, and suicidal thoughts in individuals with earthquake trauma experience: the mediatory role of peritraumatic dissociation and experiential avoidance

BMC Psychiatry volume 24, Article number: 171 (2024) Cite this article

Abstract

Background

Despite the fact that studies indicate that earthquake trauma is associated with numerous psychological consequences, the mediating mechanisms leading to these outcomes have not been well-studied. Therefore, this study investigates the relationship between trauma exposure with substance use tendency, depression, and suicidal thoughts, with the mediating role of peritraumatic dissociation and experiential avoidance.

Methods

The descriptive-correlational approach was employed in this study. The participants were people who had experienced the Kermanshah earthquake in 2017. A total of 324 people were selected by convenient sampling method. The Traumatic Exposure Severity Scale, the Peritraumatic Dissociative Experiences Questionnaire, the Acceptance and Action Questionnaire, the Iranian Addiction Potential Scale, Beck’s Depression Inventory [BDI-II], and Beck’s Suicidal Thoughts Scale were used to collect data. The gathered data was analyzed‌ using structural equation modeling in ‌SPSS Ver. 24 and LISREL Ver. 24.

Results

The study findings indicated that the intensity of the trauma exposure is directly and significantly associated with depression symptoms, peritraumatic dissociation, and experiential avoidance. The severity of exposure to trauma had a significant indirect effect on the tendency to use substances through experiential avoidance. This is while the severity of the trauma experience did not directly correlate with substance use and suicidal thoughts. In addition, peritraumatic dissociation did not act as a mediator in the relationship between the severity of trauma exposure with substance use, depression, and suicidal thoughts.

Conclusions

The severity of exposure to the earthquake was associated with symptoms of depression and these findings indicate the importance of experiential avoidance in predicting the tendency to use drugs. Hence, it is essential to design and implement psychological interventions that target experiential avoidance to prevent drug use tendencies and to establish policies that lower depression symptoms following natural disasters.

Peer Review reports

Background

Earthquakes are one of the most common natural disasters in the world [1]. Situated on the Alpine-Himalayan Seismic Belt [2], Iran is prone to these natural disasters. On November 12, 2017, an earthquake with a magnitude of 7.3 occurred in Western Iran near the Iran-Iraq border in the province of Kermanshah. The earthquake left 630 people dead, 9,388 wounded, and 70,000 homeless [3]. Many studies have shown that earthquakes have caused extensive material, human, and psychological damage in different regions of the world [4] particularly in Kermanshah [2, 3, 5]. Most studies are mainly focused on the development of post-earthquake PTSD. This is while other common psychological reactions to earthquake trauma experience can include substance use [4], depression [6], and suicidal thoughts [7]. Therefore, it is essential to understand the significant mediating mechanisms that influence the relationship between earthquakes and psychological consequences.

To comprehend the significant mediating mechanisms, one can rely on some theoretical and research foundations. Studies have shown that psychological disorders, including PTSD, can arise as a result of pre-existing psychological vulnerabilities and psychological distress following an earthquake [3, 8]. The evidence also emphasizes the importance of various types of psychological distress– dissociation– during and after the earthquake, in the formation of psychological outcomes [8, 9].

One of the key mediating mechanisms between psychological problems and earthquakes is dissociation [8, 9]. Many researchers consider dissociation as a common response to trauma [10, 11]. The dissociation model underlines that traumatized individuals can manage their distress by separating their awareness from their experience. The model suggests that peritraumatic dissociative responses (e.g., dissociative amnesia, emotional numbing, and depersonalization) indicate a strategy to reduce awareness of aversive emotions [12]. Dissociative experiences are a crucial aspect of the dissociative response to trauma, occurring during or immediately after a traumatic event, also called peritraumatic dissociation (PD) [13]. This component is a significant risk factor for PTSD and other psychological symptoms [14]. It is believed that PD occurs due to severe traumatic distress, including fear, helplessness, or trauma-induced horror [15] and it may function to regulate aversive peritraumatic affects [11]. Given the main function of dissociation in regulating specific aspects of trauma, such as aversive affect, it is not surprising to claim that dissociation is an essential factor in increasing the risk for depression [16, 17], suicidal thoughts [18,19,20], and the tendency to use drugs [21].

Drug consumers ‌may use drugs or alcohol to manage aversive affects‌ associated with traumatic dissociation. Sometimes, the substance user intends to access traumatic memories. Research also indicates higher levels of dissociation in drug users [21]. Dissociation also plays a vital role in the psychopathology of depression [22]. From a clinical point of view, depression can be explained by considering dissociation as a way of coexisting with despair. According to Pettorruso et al. [22], dissociation is a mechanism used by individuals experiencing depression to deal with stressful mental processes, tolerate the lack of positive future prospects, and emotional pain and distress. Additionally, emotional dysregulation, disinterest in social interactions, psychological distancing, excessive engagement in imagination, disturbing thoughts and memories, personality disintegration, and reality disintegration are among the signs related to dissociation that can significantly contribute to explaining depression [23, 24]. In the context of dissociation and suicidal thoughts, it can also be argued that chronic stress can lead todissociative experiences and severe vulnerability to stress, which can enhance suicidal behavior and thoughts when faced with intolerable stress, helplessness, and hopelessness [19]. In addition, dissociation can be understood as a form of detachment and can include depersonalization, derealization, amnesia, fugue states, and identity disorders [25]. Therefore, dissociation can involve a disconnection from the body that can reduce the fear and pain associated with harming the body that can make suicide attempts possible [18].

Aside from the current research, some argue that the association between the earthquake and its psychological consequences and the relationship between dissociation and psychological symptoms remain equivocal, suggesting the inclusion of some dissociative constructs, such as experiential avoidance for a better understanding of psychological phenomena related to trauma and dissociation [12, 26].

Experiential avoidance is another mediating mechanism that explains the impact of trauma on psychological consequences. An increasing number of theories and studies show that avoidance plays a significant role in the formation and maintenance of psychological symptoms among trauma survivors [27, 28]. Since PD can serve in forming avoidance or altering the aversive aspects of a traumatic event, it has been suggested that PD may be a form of experiential avoidance (EA) [27]. Experiential avoidance is a form of unwillingness to make contact with personal experiences (physical sensitivities, ‌feelings,‌ thoughts, memories‌, and ‌behavioral states) and an attempt to avoid those agonizing experiences ‌or events that cause the recollection of these experiences‌ [27]. EA controls or minimizes the impact of aversive experiences, resulting in short-term relief. As a result of this, behavior is negatively reinforced [29]. Hays et al. [27] state that trying to distance one self from internal experiences can lead to psychological and behavioral issues, such as substance use, depression, suicidal thoughts, and aggressive behaviors‌. Thus, the psychological and behavioral problems of trauma survivors may be a byproduct of the EA process.

Finally, it is important to review the literature related to the study variables. Marx, & Sloan [28] found that while EA and PD were initially ‌‌important‌ predictors of PTSD symptoms, after 4 to 8 weeks, only EA was associated with PTSD symptoms. The findings of Kumpula et al. [30] demonstrated that both EA and PD exert distinct influences as risk factors for PTSS after an event that is potentially traumatic. Different studies report increased or decreased psychological problems after earthquakes [31, 32, 33]. The role of dissociation on substance use, depression, and suicidal thoughts [20, 21, 22] and the role of EA ‌in substance use, depression, and suicidal ideation‍ [27, 34, 35] have been investigated in some studies.

Despite extensive research and significant theoretical support, the relationship between trauma and some psychological consequences (including substance use, depression, and suicidal thoughts) is still unclear. Therefore, to gain a better understanding ofthe psychological consequences associated with earthquake trauma, it is necessary to incorporate some mediating mechanisms (such as PD and EA ). In addition, since Iran is located in one of the most earthquake-prone areas in the world, identifying the psychological ‌consequences of earthquakes and their risk factors is vital: Accordingly, the present study was conducted to explore the relationship between trauma exposure and substance use tendency, depression, and suicidal thoughts in individuals with earthquake trauma experience through the mediating role of PD and EA‌.

Hypotheses of the present study:

  1. 1.

    Exposure to trauma directly affects the tendency to use substances, suicidal thoughts, and develop depressive symptoms.

  2. 2.

    Peritraumatic dissociation mediates the relationship between trauma exposure with substance use tendencies, depressive symptoms, and suicidal ideation.

  3. 3.

    Experiential avoidance mediates the relationship between trauma exposure with substance use tendencies, depressive symptoms, and suicidal thoughts.

Methods

Participants

The participants were people who had experienced the Kermanshah earthquake (residents of two cities of Sarpol-e Zahab and Salas-e Babajani) in 2017. The sample size was determined based on Kline’s [36] suggestion, which proposes a minimum sample size of 300 in SEM. In this study, to reduce the error margin and improve the generalizability of the results, a total of 323 people were selected by convenience sampling from residents struck by the earthquake. The inclusion criteria are the following: those who, at the time of the earthquake on November 12, 2017, as well as during this study, lived in one of the cities in Kermanshah (Sarpol-e Zahab Sallas-e Babajani), those who were completely fluent in the official language, and aged between 18 and 50 years. The exclusion criteria are the following: incomplete questionnaires and individuals with a history of hospitalization for substance use, depression symptoms, and suicidal thoughts before the earthquake.

Procedures

This descriptive-correlational study was conducted based on structural equation modeling (SEM).

In this study, the data collection phase from struck residents in the cities of Kermanshah started after obtaining a recommendation letter from the University of Shiraz, coordinating with the Health Department of the Kermanshah University of Medical Sciences, and obtaining the permits required. In this study, the data were collected personally by the researcher. For each subject, the tests were performed separately by the researcher in a quiet room, away from aversivevisual-auditory stimuli This research has an ethics approval certificate (IR.SUMS.REC.1400.813) issued by the Shiraz University of Medical Sciences. This study was performed in line with the principles of the Declaration of Helsinki. To implement the ethical considerations, the codes of conduct proposed by the American Psychiatric Association, including the principles of privacy and confidentiality, written consent, etc. debriefing on processes, objectives, and duration, potential losses and benefits of participation, and the permission to withdraw from the research at any stage, were taken into account.

Measures

The traumatic exposure severity scale (TESS) (earthquake-specific)

The severity of exposure to earthquakes is measured using its Persian version. The primary version of this questionnaire comprises 24 items with five sub-scales [37]. The Persian version of this questionnaire was provided by Nobakht et al. [38] and was normalized on the Iranian sample. It consists of 21 items divided into four sub-scales, including being in need/damage to home, personal harm, harm to significant others, and exposure to the grotesque. In the Persian version, participants were asked to use a 5-point Likert scale, ranging from 1 (Not at All) to 5 (To a Great Extent), to indicate the extent to which each item is distressing to them. In TESS, the distress scale was calculated by summing up the scores ranging from 1 to 5. TESS has shown in both the original [37] and Persian [38] versions that have demonstrated sufficient validity and internal consistency.

The peritraumatic dissociative experiences questionnaire (PDEQ)

The Peritraumatic Dissociative Experiences Questionnaire (PDEQ) measures PD. It is used to evaluate dissociative experiences and reactions during and immediately after a traumatic event [3]. PDEQ is a self-report measure. It consists of ten items scored on a 5-point Likert scale ranging from 1 (Not True at All) to 5 (Very True). The Persian version of this scale was normalized by Nobakht et al. [38] and demonstrated good validity, internal consistency, and reliability.

The acceptance and action questionnaire (AAQ-II)

This questionnaire was developed by Bond et al. [39]. In addition, a 10-item version of the original questionnaire (AAQ- I) was developed by Hayes et al. [40]. Psychological flexibility and experiential avoidance are measured using this questionnaire. The items are rated on a 7-point Likert scale according to the level of agreement. Higher scores on a scale indicate lower psychological flexibility and higher EA. The findings indicate that this instrument demonstrates acceptable reliability, validity, and construct validity, with a mean alpha coefficient value of 0.84. The test-retest reliability at an interval of 3 to 12 months was 0.81 and 0.79, respectively [39]. Abasi et al. [41] also demonstrated the acceptable internal consistency and convergent validity of the Persian version of this questionnaire.

The Iranian addiction potential scale (IAPS)

This questionnaire was designed by Weed et al. [42] in Iran. It was normalized by Zargar [43]. This scale consists of 41 items, 5 of which constitute the Lie scale. It has a scoring system that ranges from 0 (Completely Disagree) to 3 (Completely Agree). The scoring system will be reversed for items 6, 12,15, and 21. The total score of the questionnaire is calculated by summing all of the items’ scores, except for the Lie scale items. Items 12, 13, 15, 21, and 33 constitute the Lie scale. The scores range from 0 to 108. Higher scores indicate the higher preparedness of the individual responding to addiction. The good psychometric properties of the Iranian version of the IAPS have been confirmed [43].

Beck’s depression inventory (BDI-II)

It is a 21-item self-report questionnaire designed to assess the severity of depression and its symptoms. The statements of this questionnaire are rated on a 4-point Likert scale (from zero to three). Higher scores indicate a greater severity of depression [44]. In this test, the minimum score is 0 and the maximum score is 63. Using the test-retest method, the test reliability of the test was obtained in the 0.73–0.93 range. The correlation coefficient between this questionnaire and the Hamilton Depression Rating Scale was 0.6 [44]. This scale has also been widely used in Iran, and its psychometric characteristics have been validated [45].

Beck’s suicidal thoughts scale

Beck’s Suicidal Thoughts Scale contains 19 items. On this scale, each item has three options. This questionnaire uses a Likert Scale scoring system with scores ranging from 0 to 2. The total score for the subjects ranges from 0 to 38. In this scale, a score of 0–5 indicates the absence of suicidal ideation, a score of 6–19 indicates preparedness for suicide, and a score of 20–38 indicates an actual suicide attempt. Cronbach’s alpha (internal consistency) and concurrent reliability of this scale were 0.89, 0.83, and 0.96, respectively, displaying a significant correlation with Beck’s Hopelessness Scale and Depression Inventory [46]. According to reports, this scale’s validity and reliability are adequate for Iranian participants [47].

Statistical analysis

Descriptive statistics were used to analyze the demographics of the participants. Before conducting data analysis, the assumptions of normality and non-linearity were checked using kurtosis and skewness indices, and variance inflation factor (VIF) statistics, respectively. The Pearson correlation coefficient was utilized to determine the relationship between the main variables. Additionally, the SEM method was used to investigate the direct and mediated effects. Also, the fit indices of the model were examined to investigate if all the indices were within the acceptance range of the model. The data were analyzed using SPSS Ver.24 and LISREL.

Results

The descriptive data and correlation between the research variables

The present study sample consisted of 152 (47.1%) women and 171 (52.9%) men. Also, the mean and standard deviation of the participants’ ages were 28.83 and 7.33, respectively.

Before conducting data analysis, the assumptions of normality and nonlinearity were examined. Table 1 specifies the curvature and kurtosis values used to investigate the normal distributionof the research variables. Chou, & Bentler [48] found a cut-off point of ± 3 to be suitable for obtaining skewness. Generally, skewness index values exceeding ± 10 can be problematic in multivariable studies [49]. The obtained values for the skewness and kurtosis of the variables indicate the realization of the normality hypothesis. To investigate the non-linearity premise, the VIF and tolerance index were utilized. Since none of the values related to the tolerance index is less than 0.40 and none of the values related to VIF is over 10, the non-linearity premise is assumed to be true. Table 1 presents the central tendency, dispersion indices as well as the correlation of the research variables.

Table 1 The descriptive indices and correlation matrix of the research variables
Full size table

As shown in Table 1, trauma exposure has a significant direct relationship with the following variables at a significance level of 0.01: PD (0.17), EA (0.23), and depression symptoms (0.21). In addition, EA, and suicidal thoughts have a direct and significant relationship with PD (0.20) and depression symptoms (0.34), respectively. The symptoms of depression have a direct and significant relationship with substance use (0.13) at a significance level of 0.05.

Evaluation of the hypothesized model using SEM

The investigation yielded the following fit indices for the obtained structural model: (X2/Df = 1/461, CFI and IFI = 0.980, GFI = 0.960, RMSEA = 0.038, SRMR = 0.044). All of the indices are within the fit range of the model, based on these values. Therefore, the structure of the hypothetical model has been approved.

To investigate the direct and mediating effects, the structural equation modeling technique was used. The results are represented in Fig. 1 and in tables showing direct and indirect effects. In Fig. 1, significant paths are indicated by solid lines, while non-significant paths are indicated by dashed lines.

Fig. 1
figure 1

Standard path coefficients of research variables in the main model

Full size image

Analysis of direct effects

The direct effect of the research variables is displayed in Table 2. According to Table 2, in cases where the value of the T-statistic is out of range Z (+ 1.96 and − 1.96) or the significant level is less than 0.05, the relationship between the two variables is significant.

Table 2 Analysis of direct effects of variables and significance of estimated parameters
Full size table

It is evident that the direct path from the variable of trauma exposure to the variables of depression symptoms (T = 0.298, β = 3.079), PD (T = 3.178, β = 0.236), and EA (T = 4.002, β = 0.315) is evidently significant. Similarly, the direct path from the variable of EA to the variable of substance use tendency (T = 2.241, β = 0.166) is also significant. However, the other direct paths among other research variables do not hold significance.

Analysis of indirect effects

As shown in Table 3, the trauma exposure variable has an indirect and insignificant effect on the depression symptoms (b = 0.016, p > 0.05) and suicidal thoughts variables (b = -0.029, p > 0.05) through EA. However the indirect effect of the trauma exposure variable on the tendency to use substances through EA (b = 0.152, p < 0.05) is significant. Also, the indirect effects of trauma exposure on depression symptoms (b = -0.017, p > 0.05) substance use tendency (b = -0.086, p > 0.05), and suicidal thoughts (b = 0.002, p > 0.05) through PD are not significant.

Table 3 Analysis of indirect effects of variables in the research model
Full size table

Discussion

This study aimed to explore the relationships between trauma exposure and substance use tendency, depression, and suicidal thoughts, with the mediating role of PD and EA. The results indicated that the intensity of trauma exposure is directly and significantly linked to symptoms of depression. These results are consistent with those of Bavafa et al. [5], Gao et al. [6] and Ide-Okochi et al. [33]. An interpretation of this finding is that depression occurs after a traumatic even — loss, death of a child, injury, illness of a family member, and losing job and resources are common factors for depression [50]. In other words, natural trauma is in a way correlated with relational trauma. Hence, the loss of loved ones, and the complete destruction of the existing social network, resources, and support will have certain psychological consequences, such as depression. In addition, research evidence shows that the less severe the disaster or traumatic event, the more important pre-disaster variables such as neuroticism or a history of psychiatric disorder appear to be [51]. Besides, the more severe the stressor, the less pre-existing psychiatric disorders predict the outcome. Therefore, the severity of exposure to earthquake trauma in this research, such as damage to the home and property, personal harm, harm to significant others, and exposure to the grotesque can be seen as determinants of depression. These findings suggest the need for developing and implementing policies and interventions to decrease depression symptoms among survivors of natural disasters.

The results also indicated that the intensity of trauma exposure had a significant indirect effect on substance use tendency through EA. The results of this research are consistent with those of Shorey et al. [32] and Shameli and Sadeghzadeh [52]. The avoidance model states that when avoidance is used as a coping strategy to adapt to traumatic events, it can have different shapes, such as aggressive behavior or a tendency to use substances [53]. Poon et al. [54] argue that substance use among young after the earthquake disaster indicates that, in the absence of more adaptive mechanisms, they react to emotional disturbance with recourse to substance, which can be interpreted as a kind of failure in emotion regulation. In this research, EA was represented in the form of a tendency to use substances to avoid negative experiences related to earthquake trauma– agonizing sentiments due to the loss of resources and property, significant others, and exposure to the grotesque. Thus, the severity of exposure to an earthquake alone cannot fully explain the tendency to use substances. In that respect, the emotional reactions of individuals (such as EA) to the consequences of the earthquake are of utmost importance. The findings of this article can help enhance the current understanding of the mechanism behind the tendency to use substances and support clinical interventions that are based on the avoidance model.

Furthermore, the results did not reveal a direct relationship between the severity of trauma exposure and the tendency to use substances and have suicidal thoughts. There are contradictory results regarding an increase or decrease in substance use [4, 55, 56] and suicidal thoughts [7, 57] after trauma experience. Different assumptions have been drawn in this regard. After experiencing trauma, some individuals tend to use drugs to forget the trauma experience, alter their consciousness state, achieve numbness, and disconnect from negative feelings [58]. This is while some react to the losses and changes after the trauma with more positive and adaptive reactions. There are also many hypotheses regarding suicidal and self-harm behavior, including the suppression of dissociative feelings, avoiding acting on suicidal impulses, establishment of interpersonal boundaries, and influencing others through self-punishment [59]. Many factors, such as the severity of the disaster, helping fellow-people, support and social integrity, can explain the increase or decrease in suicide [57, 60]. Therefore, based on the arguments in this research, the intensity of earthquake trauma exposure was not a explain of substance use tendency and suicidal thoughts, suggesting there might be another unexplored mechanism involved.

In addition, the present study also found no evidence of the mediating effect of EA in the relationship between the severity of trauma exposure and depression and suicidal thoughts. The findings of this study do not align with the existing literature [27, 35]. Several factors other than experiential avoidance, such as motivation diversity, personal characteristics, and experiential avoidance measurement, may account for depression and suicidal thoughts. Suicidal thoughts are driven by various motives and are closely linked to emotional distress. These emotions include not only depression but also anxiety, shame, guilt, and other negative emotions [61]. Actually, avoidance is just one of the possible motives for suicide. Brown, Comtois, and Linehan [62] have stated that other factors, such as reducing the burden on others or influencing others. Also, some personal characteristics e.g., resilience, secure attachment, helping others, and mindfulness can function as protective factors to prevent suicide and depression. Apart from EA as one of the factors of depression, other elements can include the function of social factors, attachment style, family relationships, and intimacy. Moreover, EA is an extensive structure understanding whose dimensions on paper is difficult, making it challenging to have a broader and clearer view of this component. EA has also been extensively measured as a generalized trait [63]. Accordingly, further research in the future should be directed toward improving this meta-diagnostic concept and reducing its complexities.

The results also indicated the insignificant indirect effect of the intensity of exposure to trauma on the tendency to use substances, depression, and suicidal thoughts through PD. The findings of this study are not consistent with previous literature. Some studies have highlighted the significance of PD in substance use, depression, and suicidal thoughts [20,21,22]. Some research has also questioned the role of PD. Dancu et al. [64] stated that PD was not repeated in victims of sexual abuse. The evidence also showed that the relationship between PD and PTSD is nonlinear and correlates with other factors, such as the level of arousal [65]. Marmar et al. [66] reported that dissociation was related to PTSD after controlling factors such as exposure level, distress, locus of control, and social support. Besides, PD may even protect the individual against PTSD and other psychological consequences by limiting the encoding of trauma experiences. These factors may also explain why PD did not mediate the relationship between trauma exposure and depression symptoms in this study.

Moreover, some theorists proposed various classifications of dissociation, such as Continuum–Taxon, State–Trait, Outcome–Mechanism, adaptive-maladaptive [12]. The various methods of categorizing dissociation may have also affected the study outcomes. This study suffers from the classic problem of looking at ‘survivor data,’ meaning that we fail to realize what consequences will befall traumatized individuals without recourse to dissociation [12]. The lack of accurate measures for measuring dissociation, as well as social and cultural expectations regarding it– whether or not it can be a socially acceptable response to trauma– may also have contributed to insignificance of PD in this research. Future researchers should adopt the correlation between dissociation as an unknown component and constructs dissociative in nature to produce and improve a better understanding of the concept of dissociation, thus paving the way for a crisper understanding of the relationship between dissociation and other psychiatric phenomena. Here, unlike EA, PD could not play a significant mediating role. Moreover, the conceptual overlap of these two variables further reinforced our speculations regarding the need for more research and a more accurate assessment of PD.

Limitations and future research directions

The study samples include individuals who have experienced an earthquake. Thus, generalizing the results to other populations with different types of trauma should be done with proper caution. The study was cross-sectional; therefore, the relationships obtained cannot be interpreted as cause and effect patterns. Measures include self-reporting questionnaires. Moreover, for most participants, the long interval between the occurrence of the disaster and participation in this study (4 years after the earthquake) may influence their retrospective reports of PD. Recollecting dissociative experiences long after facing trauma can produce inaccurate reports of an individual’s actual dissociative behavior. There are also limitations regarding the ability to differentiate pre-traumatic risk factors from post-traumatic reactions. In other words, another limitation of this research is the difficulty of assessing when traumatic events occur and when psychological problems begin.

It is suggested to use more accurate clinical interviews to study PD. In addition, considering the multifaceted reactions related to trauma, the inclusion of both emotional poles (avoidance and emotional expression (can help further explain psychological problems. Future research should use longitudinal designs to examine the temporal dynamics of these variables. Furthermore, even if a model demonstrates that a variable leads to a mediator and subsequently an outcome variable, alternative models might account for the findings more adequately. Other variables (such as anger, shame and guilt, mentalization, and attachment styles) might enhance the understanding of the findings or clarify the connections more effectively.

Conclusion

In general, there are different susceptible constructs before, during, and after a trauma that can help explain the peritraumatic psychological consequences. In this research, the severity of exposure to trauma was a good explain of depression symptoms, PD and EA. This is while not only the trauma but also how individuals react to it is also of utmost importance. In this study, the severity of trauma exposure could explain the tendency to use substances through EA. Despite the insignificance of PD in this research, a more precise definition and measurement of dissociation and including EA as well as other constructs dissociative in nature can improve our understating of this component and help pave the way and undergird future research on explaining psychological consequences of disasters.

Data availability

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

References

  1. Priebe S, Marchi F, Bini L, Flego M, Costa A, Galeazzi G. Mental disorders, psychological symptoms and quality of life 8 years after an earthquake: findings from a community sample in Italy. Soc Psychiatry Psychiatr Epidemiol. 2011;46:615–21.

    Article  PubMed  Google Scholar 

  2. Basharpoor S, Aziziaram S, Heidari F. The causal modeling of post-traumatic growth in earthquake-stricken individuals based on social support, mindfulness, and rumination with mediating role of acceptance and action. Salāmat-i Ijtim. (Community Health). 2020;8(2):247–63.

    Google Scholar 

  3. Nobakht HN, Ojagh FS, Dale KY. Risk factors of post-traumatic stress among survivors of the 2017 Iran earthquake: the importance of peritraumatic dissociation. Psychiatry Res. 2019;271:702–7.

    Article  PubMed  Google Scholar 

  4. Kobayashi D, Hayashi H, Kuga H, Kuriyama N, Terasawa Y, Osugi Y, Takahashi O, Deshpande G, Kawachi I. Alcohol consumption behaviours in the immediate aftermath of earthquakes: time series study. BMJ open. 2019;9(3):e026268.

    Article  PubMed  PubMed Central  Google Scholar 

  5. Bavafa A, Khazaie H, Khaledi-Paveh B, Rezaie L. The relationship of severity of symptoms of depression, anxiety, and stress with sleep quality in earthquake survivors in Kermanshah. J Inj Violence Res. 2019;11:225–32.

    PubMed  PubMed Central  Google Scholar 

  6. Gao X, Leng Y, Guo Y, Yang J, Cui Q, Geng B, Hu H, Zhou Y. Association between earthquake experience and depression 37 years after the Tangshan earthquake: a cross-sectional study. BMJ Open. 2019;9:e026110.

  7. Matsubayashi T, Sawada Y, Ueda M. Natural disasters and suicide: evidence from Japan. Soc Sci Med. 2013;82:126–33.

    Article  PubMed  Google Scholar 

  8. Priebe S, Grappasonni I, Mari M, Dewey M, Petrelli F, Costa A. Posttraumatic stress disorder six months after an earthquake: findings from a community sample in a rural region in Italy. Soc Psychiatry Psychiatr Epidemiol. 2009;44:393–7.

    Article  PubMed  Google Scholar 

  9. Yuan KC, Ruo Yao Z, Zhen Yu S, Xu Dong Z, Jian Zhong Y, Edwards JG, et al. Prevalence and predictors of stress disorders following two earthquakes. Int J Soc Psychiatry. 2013;59:525–30.

    Article  PubMed  Google Scholar 

  10. Howell EF, Itzkowitz S. The dissociative mind in psychoanalysis. New York: Rowman; 2016.

    Book  Google Scholar 

  11. Wagner A, Linehan MM. Dissociation. In: Follette JI, Ruzek JI, Abueg FR, editors. Cognitive behavioral therapies for Trauma. New York: Guilford Press; 1998. pp. 191–225.

    Google Scholar 

  12. Friedman MJ, Schnurr PP, Keane TM. Handbook of PTSD: science and practice (3rd ed.). Guilford press: 2021.

  13. Marmar CR, Weiss DS, Schlenger WE, Fairbank JA, Jordan BK, Kulka RA, Hough RL. Peritraumatic dissociation and posttraumatic stress in male Vietnam theater veterans. Am J Psychiatry. 1994;151:902–7.

    Article  CAS  PubMed  Google Scholar 

  14. Greene T. Do acute dissociation reactions predict subsequent posttraumatic stress and growth? A prospective experience sampling method study. J Anxiety Disord. 2018;57:1–6.

    Article  PubMed  Google Scholar 

  15. Bernat JA, Ronfeldt HM, Calhoun KS, Arias I. Prevalence of traumatic events and peritraumatic predictors of posttraumatic stress symptoms in a nonclinical sample of college students. J Trauma Stress. 1998;11:645–64.

    Article  CAS  PubMed  Google Scholar 

  16. McCanlies EC, Sarkisian K, Andrew ME, Burchfiel CM, Violanti JM. Association of peritraumatic dissociation with symptoms of depression and posttraumatic stress disorder. Psychol Trauma: Theory Res Pract Policy. 2017;9(4):479.

    Article  Google Scholar 

  17. Fung HW, Chan C, Ross CA, Choi TM. A preliminary investigation of depression in people with pathological dissociation. J Trauma Dissociation. 2020;21(5):594–608.

    Article  PubMed  Google Scholar 

  18. Pachkowski MC, Rogers ML, Saffer BY, Caulfield NM, Klonsky ED. Clarifying the relationship of dissociative experiences to suicide ideation and attempts: a multimethod examination in two samples. Behav Ther. 2021;52:1067–79.

    Article  PubMed  Google Scholar 

  19. Orbach I. Dissociation, physical pain, and suicide: a hypothesis. Suicide Life Threat Behav. 1994;24:68–79.

    Article  CAS  PubMed  Google Scholar 

  20. Caulfield NM, Karnick AT, Capron DW. Exploring dissociation as a facilitator of suicide risk: a translational investigation using virtual reality. J Affect Disord. 2022;297:517–24.

    Article  PubMed  Google Scholar 

  21. Najavits LM, Walsh M. Dissociation, PTSD, and substance abuse: an empirical study. J Trauma Dissociation. 2012;13:115–12.

    Article  PubMed  PubMed Central  Google Scholar 

  22. Pettorruso M, d’Andrea G, Martinotti G, Cocciolillo F, Miuli A, Di Muzio I, Collevecchio R, Verrastro V, De-Giorgio F, Janiri L, Di Giannantonio M. Hopelessness, dissociative symptoms, and suicide risk in major depressive disorder: clinical and biological correlates. Brain Sci. 2020;10(8):519.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Ponce de León B, Andersen S, Karstoft KI, Elklit A. Pre-deployment dissociation and personality as risk factors for post-deployment post-traumatic stress disorder in Danish soldiers deployed to Afghanistan. Eur J Psychotraumatology. 2018;9(1):1443672.

    Article  Google Scholar 

  24. Kwapil TR, Wrobel MJ, Pope CA. The five-factor personality structure of dissociative experiences. Pers Indiv Differ. 2002;32(3):431–43.

    Article  Google Scholar 

  25. Niciu MJ, Shovestul BJ, Jaso BA, Farmer C, Luckenbaugh DA, Brutsche NE, et al. Features of dissociation differentially predict antidepressant response to ketamine in treatment-resistant depression. J Affect Disord. 2018;232:310–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Marmar CR, Weiss DS, Metzler TJ. The peritraumatic dissociative experiences questionnaire. In: Wilson JP, Keane TM, editors. Assessing psychological trauma and PTSD: a handbook for practitioners. New York, NY: Guilford Press; 1997.

    Google Scholar 

  27. Hayes SC, Wilson KG, Gifford EV, Follette VM, Strosahl K. Experiential avoidance and behavioral disorders: a functional dimensional approach to diagnosis and treatment. J Consult Clin Psychol. 1996;64:1152–68.

    Article  CAS  PubMed  Google Scholar 

  28. Marx BP, Sloan DM. Peritraumatic dissociation and experiential avoidance as predictors of posttraumatic stress symptomatology. Behav Res Ther. 2005;43:569–83.

    Article  PubMed  Google Scholar 

  29. Eifert GH, Forsyth JP, Arch J, Espejo E, Keller M, Langer D. Acceptance and commitment therapy for anxiety disorders: three case studies exemplifying a unified treatment protocol. Cogn Behav Pract. 2009;16:368–85.

    Article  Google Scholar 

  30. Kumpula MJ, Orcutt HK, Bardeen JR, Varkovitzky RL. Peritraumatic dissociation and experiential avoidance as prospective predictors of posttraumatic stress symptoms. J Abnorm Psychol. 2011;120:617–27.

    Article  PubMed  PubMed Central  Google Scholar 

  31. Jahangiri K, Yousefi K, Mozafari A, Sahebi A. The prevalence of suicidal ideation after the earthquake: a systematic review and Meta-analysis. Iran J Public Health. 2020;49:2330–8.

    PubMed  PubMed Central  Google Scholar 

  32. Shorey RC, Gawrysiak MJ, Elmquist J, Brem M, Anderson S, Stuart GL. Experiential avoidance, distress tolerance, and substance use cravings among adults in residential treatment for substance use disorders. J Addict Dis. 2017;36:151–7.

    Article  PubMed  PubMed Central  Google Scholar 

  33. Ide-Okochi A, Samiso T, Kanamori Y, He M, Sakaguchi M, Fujimura K. Depression, insomnia, and probable post-traumatic stress disorder among survivors of the 2016 Kumamoto earthquake and related factors during the recovery period amidst the COVID-19 pandemic. Int J Environ Res Public Health. 2022;19:4403.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Creighton G, Oliffe J, Matthews J, Saewyc E. Dulling the edges young men’s use of alcohol to deal with grief following the death of a male friend. Health Educ Behav. 2016;43:54–60.

    Article  PubMed  Google Scholar 

  35. Angelakis I, Gooding P. Obsessive–compulsive disorder and suicidal experiences: the role of experiential avoidance. Suicide Life Threat Behav. 2020;50:359–71.

    Article  PubMed  Google Scholar 

  36. Kline P. An easy guide to factor analysis. Routledge; 2014.

  37. Elal G, Slade P. (2005). Traumatic exposure severity scale (TESS): a measure of exposure to major disasters. J Trauma Stress. 2005;18:213–220.

  38. Nobakht HN, Ojagh FS, Dale KY, Validity. Reliability and internal consistency of Persian versions of the childhood trauma questionnaire, the traumatic exposure severity scale and the peritraumatic dissociative experiences questionnaire. J Trauma Dissociation. 2021;22:332–48.

    Article  PubMed  Google Scholar 

  39. Bond FW, Hayes SC, Baer RA, Carpenter KM, Guenole N, Orcutt HK, Waltz T, Zettle RD. Preliminary psychometric properties of the acceptance and action questionnaire–II: a revised measure of psychological inflexibility and experiential avoidance. Behav Ther. 2011;42:676–88.

    Article  PubMed  Google Scholar 

  40. Hayes SC, Follette VM, Linehan M, editors. Mindfulness and acceptance: expanding the cognitive-behavioral tradition. Guilford Press; 2004.

  41. Abasi E, Fti L, Molodi R, Zarabi H. Psychometric properties of Persian version of acceptance and action questionnaire–II. Psychol Methods Models. 2012;3:65–80.

    Google Scholar 

  42. Weed NC, Butcher JN, McKenna T, Ben-Porath YS. New measures for assessing alcohol and drug abuse with the MMPI-2: the APS and AAS. J Pers Assess. 1992;58:389–404.

    Article  CAS  PubMed  Google Scholar 

  43. Zargar Y, Najarian B, Naami A. Investigating the relationship between personality traits (emotion-seeking, expression, psychological hardiness), religious atitude, and marital satisfaction with educational problems. J Educ Psychol Chamran Univ. 2008;3(1):99–120.

    Google Scholar 

  44. Beck AT, Steer RA, Ball R, Ranieri WF. Comparison of Beck depression inventories-IA and-II in psychiatric outpatients. J Pers Assess. 1996;67:588–97.

    Article  CAS  PubMed  Google Scholar 

  45. Stefan-Dabson K, Mohammadkhani P, Massah-Choulabi O. Psychometrics characteristic of Beck depression inventory-II in patients with magor depressive disorder. Archives Rehabilitation. 2007;8:82–6.

    Google Scholar 

  46. Beck A, Steer R. Manual for the Beck scale for suicide ideation. San Antonio Psychol Publication. 1991;5:230–9. 5th ed.

    Google Scholar 

  47. Anisi J, Fathi Ashtiani A, Salimi SH, Ahmadi Noudeh Kh. Validity and reliability of Beck suicide scale ideation (BSSI) among soldiers. J Military Med. 2005;7(1):33–7.

    Google Scholar 

  48. Chou CP, Bentler PM. Estimates and tests in structural equation modeling. In: Hoyle RH, editor. Structural equation model: concepts, issues and applications. Thousand Oaks, CA: Sage; 1995. pp. 37–55.

    Google Scholar 

  49. Kline RB. Principles and practice of structural equation modeling. Guilford; 2015.

  50. Dalgard OS, Bj S, Tambs K. Social support, negative life events and mental health. Br J Psychiatry. 1995;166:29–34.

    Article  CAS  PubMed  Google Scholar 

  51. Lopez-Ibor JJ, Christodoulou G, Maj M, et al. editors. Disasters and mental health. Chichester: Wiley; 2005.

    Google Scholar 

  52. Shameli L, Sadeghzadeh M. Investigating the relationship between experiential avoidance and addiction potential in college students: the mediating role of emotion regulation styles. J Fundamentals Mental Health. 2019;21(4):219–28.

    Google Scholar 

  53. Gardner FL, Moore ZE. Understanding clinical anger and violence: the anger avoidance model. Behav Modif. 2008;32:897–912.

    Article  PubMed  Google Scholar 

  54. Poon JA, Turpyn CC, Hansen A, Jacangelo J, Chaplin TM. Adolescent substance use & psychopathology: interactive effects of cortisol reactivity and emotion regulation. Cogn Ther Res. 2016;40(3):368–8.

    Article  Google Scholar 

  55. Movaghar AR, Goodarzi RR, Izadian E, Mohammadi MR, Hosseini M, Vazirian M. The impact of bam earthquake on substance users in the first 2 weeks a rapid assessment. J Urban Health. 2005;82(3):370–7.

    Article  PubMed  PubMed Central  Google Scholar 

  56. Bianchini V, Roncone R, Giusti L, Casacchia M, Cifone MG, Pollice R. PTSD growth and substance abuse among a college student community: coping strategies after 2009 L’aquila earthquake. Clin Pract Epidemiol Ment Health. 2015;11:140–3.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  57. Samaan Z, Bawor M, Dennis BB, El-Sheikh W, DeJesus J, Rangarajan S, et al. Exploring the determinants of suicidal behavior: conventional and emergent risk (DISCOVER): a feasibility study. Pilot Feasibility Stud. 2015;1:1–0.

    Article  Google Scholar 

  58. Klanecky A, McChargue DE, Bruggeman L. Desire to dissociate: implications for problematic drinking in college students with childhood or adolescent sexual abuse exposure. Am J Addict. 2012;21(3):250–6.

    Article  PubMed  Google Scholar 

  59. Klonsky ED. The functions of deliberate self-injury: a review of the evidence. Clin Psychol Rev. 2007;27:226–39.

    Article  PubMed  Google Scholar 

  60. Gerstner RMF, Lara-Lara F, Vasconez E, Viscor G, Jarrin JD, Ortiz-Prado E. Earthquake-related stressors associated with suicidality, depression, anxiety and post-traumatic stress in adolescents from Muisne after the earthquake 2016 in Ecuador. BMC Psychiatry. 2020;20:347.

    Article  PubMed  PubMed Central  Google Scholar 

  61. Fawcett J, Scheftner WA, Fogg L, Clark DC, Young MA, Hedeker D, et al. Time-related predictors of suicide in major affective disorder. Am J Psychiatry. 1990;147:1189–94.

    Article  CAS  PubMed  Google Scholar 

  62. Brown MZ, Comtois KA, Linehan MM. Reasons for suicide attempts and nonsuicidal self-injury in women with borderline personality disorder. J Abnorm Psychol. 2002;111(1):198.

    Article  PubMed  Google Scholar 

  63. Akbari M, Seydavi M, Hosseini ZS, Krafft J, Levin ME. Experiential avoidance in depression, anxiety, obsessive-compulsive related, and posttraumatic stress disorders: a comprehensive systematic review and meta-analysis. J Contextual Behav Sci. 2022;24:65–78.

    Article  Google Scholar 

  64. Dancu CV, Riggs DS, Hearst-Ikeda D, Shoyer BG, Foa EB. Dissociative experiences and posttraumatic stress disorder among female victims of criminal assault and rape. J Trauma Stress. 1996;9:253–67.

    Article  CAS  PubMed  Google Scholar 

  65. Breh DC, Seidler GH. Is peritraumatic dissociation a risk factor for PTSD? J Trauma Dissociation. 2007;8:53–69.

    Article  PubMed  Google Scholar 

  66. Marmar CR, Weiss DS, Metzler TJ, et al. Characteristics of emergency services personnel related to peri-traumatic dissociation during critical incident exposure. Am J Psychiatry. 1996;153:94–102.

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

The authors sincerely appreciate the earthquake-stricken residents of Sarpol-e-Zahab and Salas-e Babajani for their contributions and cooperation in this research.

Funding

The authors received no financial support for the research, authorship and publication of this article.

Author information

Authors and Affiliations

  1. Department of Clinical Psychology, Faculty of Educational Sciences and Psychology, University of Shiraz, Shiraz, Iran

    Farshad Ahmadi, Mohammad Ali Goodarzi, Mohammad Reza Taghavi & Mahdi Imani

Authors
  1. Farshad Ahmadi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Mohammad Ali Goodarzi
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Mohammad Reza Taghavi
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Mahdi Imani
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

FA: Conceptualization, data collection, MG, MT and MI: Study design, data analysis and interpretations. All authors have read and approved the manuscript.

Corresponding author

Correspondence to Farshad Ahmadi.

Ethics declarations

Ethical approval and consent to participate

This article was derived from the first author’s doctoral dissertation in Clinical Psychology from Shiraz University. This study was conducted in accordance with the Declaration of Helsinki and all questionnaires and methodology for this study was approved by the Research Ethics Committee of Shiraz University of Medical Sciences, Iran (ethical code: IR.SUMS.REC.1400.813). Informed consent was obtained from all participants included in the study.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ahmadi, F., Goodarzi, M.A., Taghavi, M.R. et al. Modeling the structural relationships between trauma exposure with substance use tendency, depression symptoms, and suicidal thoughts in individuals with earthquake trauma experience: the mediatory role of peritraumatic dissociation and experiential avoidance. BMC Psychiatry 24, 171 (2024). https://doi.org/10.1186/s12888-024-05595-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12888-024-05595-5

Keywords

BMC Psychiatry

ISSN: 1471-244X

Contact us