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European Journal of Psychotraumatology logoLink to European Journal of Psychotraumatology
. 2023 Oct 17;14(2):2263151. doi: 10.1080/20008066.2023.2263151

A comparison of PTSD and traumatic event rates in a clinical sample of non-refugee immigrants and native-born individuals with a psychotic disorder: a case-control study

Comparación entre las tasas de trastorno de estrés postraumático y eventos traumáticos en una muestra clínica de inmigrantes no refugiados e individuos nativos con Trastornos psicóticos: un estudio de casos y controles

非难民移民和本土出生的精神障碍患者临床样本中 PTSD 和创伤事件发生率的比较：病例对照研究

Amira Trabsa a,b,c, Diego Redolar-Ripoll d, Laura Vargas b, Alba Llimona b, Bridget Hogg a,c,e,f, Alicia Valiente-Gómez b,c,e,f, Víctor Pérez b,c,f,g, Ana Moreno-Alcázar c,e,f,*, Benedikt L Amann b,c,e,f,g,*,CONTACT
PMCID: PMC10583634  PMID: 37846737

ABSTRACT

Background: Migration is a multi-stage social process linked to traumatic event exposure and a notably increased risk of psychosis. Although these conditions affect refugee and non-refugee immigrants, prior trauma research has focused mainly on the refugee population.

Objective: To compare and describe the rate and the clinical characterization of PTSD and traumatic events between non-refugee immigrants and native-born individuals with psychotic disorder.

Methods: 99 immigrants and 99 native-born individuals (n = 198) with at least one psychotic episode according to DSM-5 criteria were compared on the rate of PTSD diagnosis and traumatic events, using standardized and validated trauma scales.

Results: In the non-refugee immigrant group, 31% met diagnostic criteria for PTSD compared to only 7.1% in the native-born group. Total scores in childhood trauma and last year stressful events were 1.5 and 2 times higher in non-refugee immigrants, respectively. Likewise, cumulative lifetime trauma was three times higher in non-refugee immigrants. Finally, non-refugee immigrants reported more violent and life-threatening traumatic events than native-born individuals.

Conclusions: These results are relevant since they highlight that non-refugee immigrants with psychotic disorders are highly trauma-exposed, meaning a routine trauma assessment and a trauma-focused intervention for this population should be included in individualized treatment plans.

KEYWORDS: Non-refugee immigrants, psychosis, trauma, PTSD, migration mental health

HIGHLIGHTS

  • Traumatic events and PTSD rates in the non-refugee immigrant population with psychotic disorder have previously received scant attention.

  • This study found that in a psychotic population, 31% of the non-refugee immigrants presented a PTSD diagnosis compared to only 7.1% of the native-born individuals.

  • Compared to native-born individuals with psychosis, non-refugee immigrants with psychosis have 1.5 times more childhood trauma exposure, 2 times more stressful events in the past year and 3 times more cumulative trauma over their lifetime.

1. Introduction

Migration is the social process of people moving from their usual residence to a new place to live, either temporarily or permanently. The term ‘migrants’ includes people who are forced to migrate searching for safety from conflict/persecution (‘refugees’) and people who migrate by choice to improve their socioeconomic status (‘non-refugee immigrants’). An important and global increase in the number of migrants has been described due to different humanitarian crises worldwide (The International Organization for Migration (IOM)-United Nations, 2020). According to United Nations data, the number of international migrants in 2020 was 280.6 million (United Nations, 2020). Furthermore, according to the UN Refugee Agency (UNHCR-The UN Refugee Agency, 2020), in 2022, about 11 million people from Ukraine left their country and fled to neighbouring and European countries. Migration is a social process associated with multiple stress factors that can increase the likelihood of migrants being exposed to traumatic events (Bustamante et al., 2018; Sangalang et al., 2018), within the pre-, peri-, and post-migration stages (Bustamante et al., 2018; Fortuna et al., 2008; Gong et al., 2011; Rasmussen et al., 2012; Sangalang et al., 2018). In terms of the type of trauma experienced, imprisonment, war, torture, and other life-threatening situations are usually associated with but not limited to the refugee population (Bustamante et al., 2018; Fortuna et al., 2008; Gong et al., 2011; Rasmussen et al., 2012; Sangalang et al., 2018; Wilson et al., 2013). However, non-refugee immigrants can also be exposed to substantial traumatic events such as political violence, physical and verbal assaults, detention and other human rights abuses (Eisenman et al., 2003; Gong et al., 2011; Rasmussen et al., 2012). For both groups traumatic factors and stressful life events associated with migration experience can potentially have an impact on migrants’ mental health (Gatt et al., 2019; Steel et al., 2017), as trauma exposure is frequently multiple and persisting, leading to a cumulative effect (Myers et al., 2015). In this sense, immigrants, when compared to native-born populations, present higher prevalence of mental disorders such as anxiety, post-traumatic stress disorder (PTSD), and depression, according to the reports from World Health Organization (WHO) (World Health Organization, 2021). A recent meta-analysis estimated that PTSD prevalence in migrants was 25% (Amiri, 2022), which is significantly higher than the general population prevalence data (0.2% to 3.8%) (Shalev et al., 2017). Furthermore, migrants have higher overall trauma exposure rates compared to the general population (Bustamante et al., 2018; Garcini et al., 2017; Kieseppä et al., 2021; Sangalang et al., 2018). Evidence suggests that 71.3% of migrants have experienced at least one lifetime trauma and 70.3% of them have two or more traumatic events (Wilson et al., 2013). It is well established in the general population that experiencing multiple traumatic events leads to poorer functioning compared to a single event exposure (Boykin et al., 2020; Cougle et al., 2009; Stuart & Nowosad, 2020; Trabsa et al., 2022).

Of note, meta-analyses have shown that migrants are at more than double the risk of experiencing a non-affective psychotic disorder (Bourque et al., 2011; Cantor-Graae & Selten, 2005; Selten et al., 2019). Furthermore, individuals with psychosis and a comorbid PTSD diagnosis present more severe psychotic symptoms, greater distress, and reduced quality of life (Fan et al., 2008; Steel et al., 2011).

Even though the proportion of non-refugee migration is higher, trauma migration literature has to date focused mainly on refugees and asylum seekers (Rasmussen et al., 2012; Wilson et al., 2013). This lack of research is even more pronounced in non-refugee immigrants with psychotic disorders within mental health services (Wilson et al., 2013). This is particularly important considering that individuals who present psychotic disorders report, independently of migrant status, higher rates of trauma exposure compared to the general population (Kilcommons & Morrison, 2005; Mueser et al., 1998). Additionally, a previous meta-analysis has estimated rates of PTSD in individuals with psychotic disorders at 12.4% (Achim et al., 2011). However, other studies reported rates around 30%, which highlights the considerable variability across previous research (Lu et al., 2011; Resnick et al., 2003; Steel et al., 2011).

Accordingly, the aim of this study is to describe and compare PTSD diagnosis rates and traumatic event exposure between non-refugee immigrants and native-born individuals, in all cases, with a diagnosis of a psychotic disorder. We hypothesized hereby that trauma exposure and PTSD are more prevalent in non-refugee immigrants with a psychotic disorder compared to the native-born group.

2. Methods

2.1. Participants and procedures

A cross-sectional descriptive study was performed at the inpatient and outpatient psychiatric units of Hospital del Mar, Barcelona, Spain. The Hospital del Mar catchment area covers around 40% of Barcelona (305,000 inhabitants) and comprises three hospitals and multiple outpatient clinics and includes the neighbourhoods with the highest proportion of immigrants in Barcelona. 198 participants (99 non-refugee immigrants and 99 native-born people) were recruited between June 2020 and July 2021. The participants in our project were recruited through convenience sampling. We used various institutional resources to identify and approach potential participants, including referrals from the acute and subacute psychiatric inpatient wards of the three hospitals, referrals from our outpatient clinics, and admissions and discharge lists. Although this sampling method has some limitations in representativeness, it allowed us to gather data from naturalistic clinical populations, enhancing the generalizability of our findings within similar settings.

Inclusion criteria were: (1) aged between 18–65 years; and (2) diagnosed with psychotic disorders according to the International Classification of Diseases 10th revision (ICD-10), including F.29 nonspecific psychosis, F.20 schizophrenia, F.25 schizoaffective disorders, and F.22 delusional disorder. Exclusion criteria were: (1) a psychotic disorder due to an organic cause or substance-induced acute intoxication according to ICD-10 criteria; (2) cognitive impairment according to a Mini-Mental State Examination (MMSE) score < 24; (3) currently in an acute psychotic episode; or (4) presence of a relevant language barrier (unable to communicate in either Spanish or English).

Local ethics committee approval was obtained for this study from the Comité Ético de Investigación Clínica del Parc de Salut Mar, Barcelona (No. 2019/8398/I) in accordance with the principles stated in the Declaration of Helsinki (WMA, 2022). Participation in the study was voluntary, and informed written consent was obtained from all participants. Where necessary, informed consent was also offered in English. The study protocol was registered at ClinicalTrials.gov (ID: NCT04867447).

2.2. Instruments

Interviews were conducted in Spanish (163 individuals) or English (35 individuals), depending on patient language preference. Sociodemographic data and clinical and migration history were collected through a specifically designed questionnaire and complemented by information from medical records. Data for clinical and trauma variables were gathered through validated scales available in both English and Spanish. Where English was necessary, bilingual evaluators who had been trained in cultural competence applied the scales and specifically designed questionnaires in English.

2.2.1. Sociodemographic data and medical history

Age, sex, country of origin, race, religion, marital status, descendants, employment status, and education level were included as sociodemographic variables. Clinical variables included: main psychiatric diagnosis following ICD-10 criteria, comorbid psychiatric and somatic diagnoses, family psychiatric history, and current and past substance use.

2.2.2. Migration process

In the group of non-refugee immigrants, the following variables were obtained: first-generation immigrant status, refugee status, total number of migrations, age at first migration, transportation method during the migration to Spain, main reason for emigration, level of accompaniment during the migration, current legal status in Spain, and other acculturation issues (past and current language barrier and job status).

2.2.3. Trauma assessment

Trauma assessment was performed using the following instruments:

  1. Global Assessment of Posttraumatic Stress Questionnaire in Spanish (EGEP-5) (Crespo & Gómez, 2012): This scale determines a PTSD diagnosis according to DSM-5 criteria. This clinician-applied scale comprises three areas with a total of 55 items: (1) traumatic events; (2) PTSD symptoms (avoidance, intrusion, cognition, mood, arousal, and reactivity alterations); and (3) impact on functioning, or social or occupational impairment. For 35 individuals, an evaluation was required in English. As this scale is validated only in Spanish, we translated this scale into English, which was then used by a bilingual evaluator.

  2. The Holmes-Rahe Life Stress Inventory English (Holmes & Rahe, 1967) with its validated version in Spanish (de Rivera et al., 1983): 43-item scale used to assess exposure to stressful life events in the last year. Each stressful event is related to a standardized impact score. The total scores are presented in two measures: total number of stressful events and total impact score. Scores <150 suggest low stress, 150–299 scores suggest moderate stress (50% risk of near future illness) and >300 scores suggest high level of stress (80% risk of near future illness) (Blasco-Fontecilla et al., 2012; Rahe et al., 1970).

  3. Childhood Trauma Questionnaire English (CTQ) (Bernstein et al., 1994) with its validated version in Spanish (Hernandez et al., 2013): The CTQ is a 28-item scale used to measure abuse and neglect during childhood. Each item is rated on a 5-point Likert scale (from ‘never’ to ‘very often’). This instrument presents five subscales for trauma measurement: emotional/physical/sexual abuse, and emotional/physical neglect.

  4. Cumulative Trauma Scale English (CTS) (Kira et al., 2008) with its validated version in Spanish (Robles et al., 2009): This scale assesses exposure to 33 traumatic events in populations such as prisoners, refugees, or mental health patients. Type of experience and level of distress are both assessed for each item on a 7-point Likert scale (from ‘1-extremely positive to 7-extremely negative’). Events that score a positive or neutral experience were excluded from the total scores used for the analyses. Specifically for our analysis, we clustered the traumatic events in nine domains: disasters, accidents, war and torture, social stress, loss of loved ones, violence, sexual trauma, negligence, and discrimination (Kira et al., 2008).

2.2.4. Further clinical assessment

  1. Positive and Negative Syndrome Scale (PANSS) (Kay et al., 1987) and its validated version in Spanish (Martín & Zorita, 1994): The PANSS is a 30-item scale used to measure positive and negative psychotic symptoms and general psychopathology symptoms. Each item is scored on a 7-point scale according to symptom severity.

  2. Mini-Mental State Examination (MMSE) (Folstein et al., 1975) and its validated version in Spanish (Llamas-Velasco et al., 2015): The MMSE is an 11-item scale used to detect cognitive impairment. Total scores <15 indicate the presence of moderate cognitive impairment, which was an exclusion criterion in our study, considering that significant cognitive impairment could affect their capacity to understand the questionnaires or interfere in the capability to recall traumatic events.

2.3. Data analysis

2.3.1. Sample size calculation

Facing the impossibility of obtaining valid data about the prevalence of PTSD in this population, a correlation test was carried out to determine the sample size using the GRANMO Sample Size Calculator (Marrugat & Vila, 2012). The sample size was calculated to detect low correlations (R = 0.30) with a statistical power of 80% and a type I error rate of 0.05, resulting in a sample size of n = 198.

2.3.2. Statistical analysis

STATA Statistics software, version 16.1 (StataCorp LLC, Texas, USA) was used to perform the analysis. For each variable, fitness to parametric assumptions were reviewed. To ensure random sampling from normal populations with equal variance, we used Shapiro–Wilk and Levene tests, and to check sphericity assumption, we used the Mauchly test.

The aim of this study is to describe and compare PTSD diagnosis rates and traumatic events exposure between non-refugee immigrants and native-born individuals with a diagnosis of a psychotic disorder. We hypothesized hereby that trauma exposure and PTSD are more prevalent in non-refugee immigrants with a psychotic disorder compared to the native-born group.

For the descriptive analysis of migration process, clinical, sociodemographic, and trauma data, we utilized the arithmetic mean (quantitative variables) and proportions (categorical variables). We also calculated the standard error and 95% confidence interval for both types of variables. We have also conducted the sub-analysis to investigate the relationship between PANSS scores and trauma symptoms reported in the supplementary materials (Tables 1 and 2 in supplementary materials).

Finally, multivariable analysis was conducted to test the potential moderating impacts of variables that revealed significant differences between the groups. Logistic regression models were used to examine categorical variables whereas linear regression models were used to analyse quantitative variables.

Concretely, the independent or exposure variable was migration status (immigrant/native-born), while the dependent or response variables were trauma exposure variables: diagnosis of PTSD (measured by EGEP-5), childhood trauma (measured by CTQ total score), stressful events in the previous year (measured by the Holmes-Rahe Life Stress Inventory total events score) and lifetime cumulative trauma (measured by CTS total score). Additionally, as mentioned above, we analysed whether the relationship between exposure and response could be modulated by the variables that revealed significant differences between the groups: age, job status, comorbid psychiatric diagnosis, and total negative PANSS score.

3. Results

3.1. Sociodemographic data of the whole sample

The mean age of the non-refugee immigrant group (33.3 years) was significantly lower than the native-born group (40.1 years) (F190 = 3.8, p = .00). Although no significant differences in sex proportion were found between groups, both had a higher proportion of men (73.7% in the non-refugee immigrants, 71.1% in the native-born group). The majority of the sample was single in both groups (70.7% of non-refugee immigrants and 79.8% of locals). Education, measured by average number of years studied, was similar in both groups: 9.81 years in non-refugee immigrants and 9.8 years in native-born individuals. In contrast, differences in employment status were found (F8 = 64.2, p = .00): 71.7% of psychotic non-refugee immigrants were unemployed, which was only true for 30.3% of the native-born group. In addition, 5.1% of the non-refugee migrant group had an illegal work status, whereas none of the native-born patients were in this situation. Finally, 53.5% of patients in the native-born group received a welfare allowance for mental impairment, whereas only 7.1% of the non-refugee immigrants received this sort of allowance (see Table 1).

Table 1.

Comparison of sociodemographic characteristics between non-refugee immigrants (cases) and native-born individuals (controls). Data are presented as mean (SD) or number (%).

Variable Group Obs/Freq Mean (SD)/Percentage* Contrast statistics
Gender Female Case 26 26.3% F1 = 0.1
p = .75
Control 28 28.3%
Male Case 73 73.7%
Control 71 71.7%
Age Case 99 33.3 (10.2) F190 = 3.8
p = .00
Control 99 40.1 (12.2)
Education (years of studies) Case 99 9.8 (3.2) F196 = 4.5
p = .91
Control 99 9.8 (3.9)
Relationship status Single Case 70 70.7% F3 = 3.8
p = .15
Control 79 79.8%
Married/in a couple Case 21 21.2%
Control 18 18.2%
Divorced Case 7 7.1%
Control 1 1.0%
Widowed Case 1 1.0%
Control 1 1.0%

Employment status		 Student Case 4 4.0% F8 = 64.2
p = .00
Control 2 2.0%
Full-time employment Case 6 6.1%
Control 3 3.0%
Part-time employment Case 3 3.0%
Control 4 4.0%
Sick leave Case 3 3.0%
Control 7 7.1%
Unable to work and receiving welfare allowance for health problems Case 7 7.1%
Control 53 53.5%
Unemployed without welfare allowance Case 71 71.7%
Control 30 30.3%
Illegal work Case 5 5.1%
Control 0 0%
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Notes: Obs/Freq: Number of cases observed/Frequency; SD: Standard Deviation.

*Age and education data are presented as means. The rest of the variables are presented as percentages.

3.2. Cultural characteristics and migration data of the non-refugee immigrants

In our sample, non-refugee immigrants originated from 36 diverse countries. Most of them were originally from North Africa (25.3%) and South America (23.2%). The dominant race was Caucasian (52.5%) followed by Black African (18.5%). Regarding their religious beliefs, the predominant religious group were Muslims (37.4%) followed by Christians (29.3%). The mean number of total non-refugee migrations was 1.73 migrations, the mean age at first migration was 20.5 years, and the mean number of years since first migration was 12.8 years. An illegal transportation method (e.g. arriving in small boats or under trucks) was used by 24.2% of the individuals to enter Spain and 32.3% still maintain an illegal status (undocumented). Most individuals had an economical reason for migration (64.6%) and 50.5% of the individuals migrated unaccompanied. Lastly, 70.7% of the individuals presented a language barrier on arrival to Spain, which is still present in 35.4% (see Table 2).

Table 2.

Cultural characteristics and migration process in the non-refugee immigrant group. Data are presented as mean (SD) or number (%).

Variable Obs/Freq Mean (SD)/Percentage*
Age at first migration 99 20.5 (8.9)
Total number of migrations 99 1.3 (1.7)
Years since migration 99 12.8(11.2)
Origin North Africa 25 25.3%
Africa 12 12.1%
South America 23 23.2%
Central America 1 1.0%
North America 1 1.0%
Eastern Asia 8 8.1%
Southeast Asia 7 7.1%
Middle East 8 8.1%
Western Europe 12 12.1%
Eastern Europe 7 7.1%
Race Caucasian 52 52.5%
Black African 18 18.2%
Asian 5 5.1%
Southeast Asian 7 7.1%
American 17 17.2%
Religion Christianism 29 29.3%
Islam 37 37.4%
Buddhism 3 3.0%
Atheism 22 22.2%
Others 8 8.1%
Legal status Documented 67 67.7%
Undocumented 32 32.3%
Transportation during migration Legal 74 74.7%
Illegal 25 24.2%
Main reason for migration Economical 65 64.6%
Political 1 1%
Both 9 9.1%
Studies 8 8.1%
Others 14 14.1%
Accompaniment during migration Alone 50 50.5%
With family 45 45.5%
With friends 4 4%
Language barrier on arrival Yes 70 70.7%
No 29 29.3%
Current language barrier Yes 35 35.4%
No 64 64.6%
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3.3. Clinical and medical history data comparison between groups

From the total sample, 93.9% of the individuals were recruited from inpatient units. No significant differences were found in the inpatient rate between immigrants (97.0%) and native-born individuals (90.9%) (F1 = 3.19, p = .074). Likewise, no significant differences were found between groups in terms of the main diagnosis. The most frequent main diagnosis in the non-refugee immigrants was psychotic disorder not otherwise specified (NOS) (49.5%). In the native-born group the most frequent main diagnosis was jointly schizophrenia (37.4%) and psychotic disorder not otherwise specified (37.4%). These diagnostic differences could be influenced by: (1) cultural barriers that contribute to the use of more generalized diagnoses (Bhui et al., 2007; Díez & Sobradiel, 2010); (2) the younger average age of the participants from the non-refugee immigrant group, which may mean a shorter disease duration at time of study entry and consequently psychotic disorder NOS diagnosis; and (3) poorer adherence to mental health services described in immigrant populations that may increase difficulties in establishing a chronic diagnosis such as schizophrenia (Betancourt et al., 2003). The native-born group showed a significantly higher proportion of patients who had another comorbid psychiatric disorder (18.2%) compared to the non-refugee group (4%) (F1 = 10.0, p = .00). No significant differences were found between groups in relation to somatic comorbidities, family history of psychosis, psychoactive substance use, or suicide attempts. Finally, in the PANSS scores, significant differences between groups were only found in the negative symptom subscale, which was higher in the native-born group (18.3) compared to the non-refugee immigrant group (14.2), (F195 = 0.86, p = .001) (see Table 3).

Table 3.

Comparison of clinical characteristics between non-refugee immigrants (cases) and native-born individuals (controls). Data are presented as mean (SD) and/or number (%).

Variable Groups Obs/Freq Mean (SD), Conf/Percentage* Contrast statistics
Main diagnosis Schizophrenia Case 32 32.3% F3 = 6.0
p = .11
Control 37 37.4%
Schizoaffective disorder Case 16 16.2%
Control 25 25.3%
Psychosis NOS Case 49 49.5%
Control 37 37.4%
Delusional disorder Case 2 2.0%
Control 0 0.0%
Comorbid psychiatric diagnosis Yes Case 4 4.0% F1 = 10.0
p = .00
Control 18 18.2%
No Case 95 96.0%
Control 81 81.8%
Organic comorbidity Yes Case 4 4.0% F1 = 0.9
p = .35
Control 7 7.1%
No Case 95 96.0%
Control 92 92.9%
Family psychiatric history Yes Case 38 38.4% F1 = 0.3
p = .56
Control 42 42.4%
No Case 61 61.6%
Control 57 57.6%
Suicide attempts Yes Case 15 15.2% F1 = 2.1
p = .15
Control 23 23.2%
No Case 84 84.8%
Control 76 76.8%
Current psychoactive substance use Yes Case 36 36.4% F1 = 0.2,
p = .66
Control 39 39.4%
No Case 63 63.6%
Control 60 60.6%
Past psychoactive substance use Yes Case 52 52.5% F1 = 0.3,
p = .57
Control 56 56.6%
No Case 47 47.5%
Control 43 43.4%
PANSS Positive symptoms Case 99 13.1 (5.4), −1.67–1.73 F196 = 2.8,
p = .97
Control 99 13.1 (6.7), −1.67–1.73
Negative symptoms Case 99 14.2 (8.4), 1.7–6.5 F195 = 0.86,
p = .001
Control 99 18.3 (8.6), 1.7–6.5
General symptoms Case 99 28.5 (9.9), −1.4–4.3 F196 = 0.01,
p = .302
Control 99 29.98 (10.3), −1.4–4.3
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Notes: Obs/Freq: Number of cases observed/Frequency; SD: Standard Deviation; Conf.: Confidence; Psychosis NOS: Psychosis Not Other Specified, PANSS: Positive and Negative Syndrome Scale.

*Scales data are presented as means. The rest of the variables are presented as percentages.

3.4. Trauma exposure and PTSD rates comparison between groups

According to the EGEP-5, a total of 39 patients (19.69%) fulfilled criteria for a current PTSD diagnosis, and 32.3% of the non-refugee immigrants met criteria for PTSD, compared to only 7.1% of the native-born group (F1 = 19.9, p = .00). Traumatic events most associated with PTSD diagnosis in the non-refugee immigrant group were ‘violent death of loved ones’ (33.1%), ‘physical violence’ (21.9%) and ‘terrorism and torture’ (15.6%), while in the native-born group it was ‘physical violence’ (28.6%). Both groups showed similar average intensity scores across all PTSD criteria symptoms except for avoidance, where native-born scored higher (5.1 compared to 3.5 for non-refugee immigrants). Significant differences were detected in the number of areas where functioning was impacted, with non-refugee immigrants presenting one more affected area (5.1) than the native-born group (4.3) (F7 = 3.9, p = .05) (see Table 4).

Table 4.

Comparison of clinical variables of psychological trauma between non-refugee immigrants(cases) and native-born individuals (controls).

Variable Group Obs/Freq Mean/Proportion Std. Err. [95%Conf.Interval] Contraststatistics
EGEP-5 PTSD Case 32 32.3%       F1 = 19.96
p = .00
Control 7 7.1%      
No PTSD Case 92 67.7%      
Control 67 92.9%      
Holmes& Rahe Number ofevents Case 99 10.91 (4.51) 0.45 −6.93–(−4.61) F189 = 5.54
p = .02
Control 99 5.14 (3.74) 0.38
Total score Case 99 356.06(142.48) 14.32 −227.72–(−152.56) F193 = 2.93
p = .00
Control 99 165.92(125.04) 12.57
CTQ Total Case 99 56.70 (18.28) 1.84 −22.01–(−12.64) F188 = 5.19
p = .02
Control 99 39.37(15.0) 1.51
EmotionalAbuse Case 99 13.39(5.64) 0.57 −5.91–(−3.00) F189 = 7.91
p = .005
Control 99 8.94(4.67) 0.47
PhysicalAbuse Case 99 12.33(7.07) 0.71 −7.04–(−3.75) F163 = 44.85
p = .000
Control 99 6.94(3.93) 0.44
SexualAbuse Case 99 7.34(5.35) 0.43 −1.93–(−0.36) F196 = 3.56
p = .061
Control 99 6.56(4.97) 0.39
EmotionalNeglect Case 99 13.72(4.63) 0.4 −4.59–(−1.70) F194 = 20.70
p = .000
Control 99 10.57(4.97) 0.50
PhysicalNegelect Case 99 10.49(4.63) 0.46 −4.64–(−2.47) F165 = 5.19
p = .024
Control 99 6.94(2.93) 0.29
CTS Number ofevents Case 99 16.12(5.08) 0.51 −11.96–(−9.49) F177 = 12.80
p = .00
Control 99 5,39(3,61) 0.36
Totaldistress Case 99 97.13(39.85) 4.00 −78.87–(−60.91) F150 = 48.99
p = .00
Control 99 27.24(21.37) 2.14
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Notes: Obs/Freq: Number of cases observed/Frequency; Std. Error: Standard Error; Conf.: Confidence; EGEP-5: Global Assessment of Post-traumatic Stress Questionnaire-5; PTSD: Post-traumatic Stress Disorder; CTQ: Childhood Trauma Questionnaire; Holmes & Rahe: Holmes & Rahe Social Readjustment Scale, CTS: Cumulative Trauma Scale.

Concerning stressful life events exposure in the past year, significant differences were found in the Holmes and Rahe scale between groups. The non-refugee immigrants presented approximately twice as many events (10.9) as the native-born group (5.1) (F189 = 5.5, p = .02). In addition, the total score was significantly higher in the immigrant group, with a mean of 356.1 compared to 165.9 in the native-born group (F193 = 2.9, p = .00) (see also Table 4).

Regarding childhood trauma, important differences in the CTQ scores were also detected. The mean CTQ total score was 56.7 in the non-refugee immigrants and 39.4 in the native-born group (F188 = 5.2, p = .02). The mean total score in each of the CTQ subscales was significantly higher in the non-refugee group, except for sexual abuse, where no significant difference was found (see Table 4).

Next, remarkable differences in lifetime cumulative trauma exposure were detected using the CTS. The mean total number of events participants were exposed to was three times higher in the non-refugee immigrants (16.1) compared to the native-born group (5.4) (F177 = 12.8, p = .00). In addition, these differences were more pronounced when total traumatic distress was compared between groups, with a mean of 97.1 in the immigrants and 27.2 in the native-born group (F150 = 48.9, p = .00) (see Table 4). The most prevalent traumatic event categories in each group are presented in Table 5. When the traumatic events assessed by CTS were grouped by clusters and compared between groups, significant differences between groups were found in all domains except in social stress cluster (see Table 6).

Table 5.

Comparison of the five traumatic lifetime events most frequently presented in each group according to the CTS, and the proportion of exposure in each group.

  Non-refugee immigrants Native-born individuals
1st Uprooting
(82.8% immigrants, 4% native-born group) 		School failure
(42.4% native-born group, 70.7% immigrants)
2nd Physical abuse
(76.8% immigrants, 36.4% native-born group) 		Serious disease
(38.4% native-born group, 69.7% immigrants)
3rd Ethnic discrimination
(74.7% immigrants, 4% native-born group) 		Accidents
(36.4% native-born group, 66.7% immigrants)
4th Threat of death
(74.7% immigrants, 15.2% native-born group) 		Physical abuse
(36.4% native-born group, 76.8% immigrants)
5th Life-threatening or disabled close friend
(72.2% immigrants, 19.2% native-born group) 		Interpersonal relationship rejection
(36.4% native-born group, 71.7% immigrants)
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Note: CTS: Cumulative Trauma Scale. Variables are presented as percentages.

Table 6.

Comparison of the proportion of traumatic events, grouped by clusters according to the CTS, in non-refugee immigrants and native-born individuals.

Trauma CTS cluster Group Mean (SD) Std. Err. [95% Conf. Interval] Contrast statistics
Disasters Case 0.43 (0.49) 0.03 −0.48– (−0.25) F147 = 241.07
p = .00
Control 0.07 (0.26) 0.05
Accidents Case 1.36 (0.79) 0.08 −0.82– (−0.40) F194 = 3.11
p = .00
Control 0.75 (0.72) 0.72
War and torture Case 0.84 (1.06) 0.11 −0.88– (−0.43) F127 = 106.28
p = .00
Control 0.18 (0.41) 0.42
Social stress Case 3.97 (1.31) 0.13 −2.72– (−1.98) F196 = 0.24
p = .62
Control 1.61 (1.30) 0.13
Physical violence Case 4.14 (2.10) 0.21 −3.43– (−2.43) F171 = 7.62
p = .00
Control 1.21 (1.42) 0.14
Discrimination Case 2.65 (1.54) 0.16 −2.30– (−1.57) F162 = 6.04
p = .00
Control 0.71 (0.96) 0.96
Sexual trauma Case 0.67 (0.96) 0.96 −0.54– (−0.49) F186 = 16.31
p = .00
Control 0.37 (0.76) 0.77
Negligence Case 0.47 (0.73) 0.74 −0.54– (−0.21) F143 = 85.91
p = .00
Control 0.10 (0.36) 0.37
Lost of loved one Case 1.50 (0.80) 0.80 −1.32– (−0.90) F191 = 6.45
p = .00
Control 0.38 (0.68) 0.68
Open in a new tab

Notes: SD: Standard Deviation, Std. Error: Standard Error; Conf.: Confidence; CTS: Cumulative Trauma Scale.

Lastly, after adjusting for sociodemographic and clinical variables that displayed significant differences between immigrants and locals (age, job status, comorbid psychiatric diagnosis, and total negative PANSS score) in relation to differences in trauma outcomes, only the age and job status variables exhibited a minor modulating effect on the association between groups and trauma exposure rates (Table 3, supplementary material).

4. Discussion

To our knowledge, this is the first study to investigate differences in PTSD, trauma exposure, and trauma-related symptoms between non-refugee immigrants and native-born patients diagnosed with a psychotic disorder. This study reveals an alarming difference in PTSD rates between non-refugee immigrants and native-born people with a psychotic disorder. According to the EGEP-5 results, 32.2% of the non-refugee immigrants meet criteria for PTSD, compared to just 7.1% of the native-born group. Furthermore, the rates of stressful life events and childhood trauma were found to be significantly higher in the non-refugee immigrants than native-born group. This is noteworthy considering that psychological trauma is per se considered to be a transdiagnostic risk for psychiatric disorders, including psychosis, regardless of whether migrant status is considered or not (Hogg et al., 2022; Kilcommons & Morrison, 2005; Mueser et al., 1998).

Our findings align with a previous study from Ireland (Wilson et al., 2013), where PTSD prevalence was assessed in a psychiatric population with heterogeneous diagnoses, showing similar PTSD rates to our study, with 31.2% in immigrants versus 6.1% in the native-born group. Another work assessed PTSD specifically in patients with a psychotic disorder and found PTSD rates of around 30%, but they did not differentiate prevalence rates according to their migrant status (Lu et al., 2011; Resnick et al., 2003; Steel et al., 2011). In our non-refugee immigrant group, traumatic events most associated with PTSD were ‘violent death of loved ones’ followed by ‘physical violence’ and ‘terrorism and torture’. This is of interest, as war-related trauma is frequently associated with refugees or forced immigrants (Rasmussen et al., 2012; Stuart & Nowosad, 2020), but these severe trauma forms also occur in voluntary immigrants. Within individuals with a PTSD diagnosis, immigrants showed similar intensity scores across all PTSD symptoms, except for avoidance, which was higher in natives. We hypothesize that this could be explained by the stressful context of migration resettlement (Bustamante et al., 2018; Sangalang et al., 2018), which forces individuals into ‘survival mode’, leading individuals to show less avoidance.

Moreover, the PTSD scale showed non-refugee immigrants were, on average, affected in one more area of functionality than the native-born group. Our results are consistent with previous research in the general population exposed to disasters, that shows that post-traumatic stress symptoms cause worse social and work adjustment, even when compared to post-disaster physical illness conditions (Cougle et al., 2009; Trabsa et al., 2022).

We also found remarkable differences in stressful events experienced during the last year. The group of immigrants had experienced during the previous year an average of 10.9 stressful events with an average distress score of 356.1. Impact scores above 300 suggest high levels of stress, resulting in an 80% risk of physical and mental illness in the near future (Blasco-Fontecilla et al., 2012; Rahe et al., 1970). Considering that, in our immigrant sample, an average of 12.8 years had occurred since migration, we assume that these scores are correlated mostly with post-migration adversities. Robust evidence describes migrants’ exposure to social adversities during all phases, including post-migration stage (Rasmussen et al., 2012; Sangalang et al., 2018). Interestingly, there is emerging evidence that describes an association between adversities during different migration stages and increased risk of psychosis (Stilo et al., 2017; Tarricone et al., 2022).

We found that a high number of the total sample experienced childhood trauma. Again, the sample of non-refugee immigrants showed statistically significantly higher scores in the CTQ total and subscales scores for physical and emotional abuse and neglect. This is also in line with previous research that suggested that individuals with psychotic disorders, and independent of their migration status, had a higher exposure to childhood trauma (Morgan et al., 2020; Rosenfield et al., 2022; Sideli et al., 2020; Varese et al., 2012). These results have relevant clinical implications, since in individuals with psychotic disorders, comorbid childhood trauma has been associated with a more severe disease course and a greater number of hospitalizations (Aas et al., 2016; Levine et al., 2014).

Contrary to expectations, no significant differences were found in levels of childhood sexual abuse. These results might be explained by the fact that women, who are more exposed to sexual abuse (Oram et al., 2017), were underrepresented in the total sample (27.3%). Another possibility is that this information was withheld by participants due to stigma.

Finally, we found further evidence of a high global trauma burden in non-refugee immigrants, as they were three times more likely than the native-born patients to be exposed to lifetime trauma. These findings highlight the significant burden of cumulative trauma among non-refugee immigrants throughout their lifetime. This is consistent with previous research describing how the trauma exposure associated with the experience of migration is usually multiple, accumulated, and life-long (Myers et al., 2015; Tarricone et al., 2022). These findings of accumulated and repetitive traumatic events may support the concept of re-traumatization, which means that a previous trauma may enhance reaction to subsequent stressful events and later trauma exposure may amplify responses to less stressful previous events (Cougle et al., 2009; Stuart & Nowosad, 2020; Trabsa et al., 2022).

Regarding the nature of traumatic events in both groups, we found more severe and life-threatening traumatic events or traumatic events related to migrant status, such as ethnic discrimination or uprooting in the non-refugee immigrant group. On the contrary, the native-born group revealed more psychosocial adverse events, such as school failure, serious disease, and interpersonal relationship rejection, which might also be related to the illness itself. These findings highlight that not only refugees, but non-refugee immigrants could also be exposed to substantial violent traumatic events.

When traumatic lifetime events were clustered in nine domains, we found significant differences in all clusters except for social stress. These results can be explained by the fact that, as mentioned above, social stress could be related to the psychosis diagnosis, which is a condition that both groups share.

Finally, after conducting multivariate analyses, a slight modulation was observed between age, job status, and the rates of trauma among groups. This could be explained by, respectively, older individuals having had more time for trauma exposure, and worse job opportunities often being linked to greater social adversity and potentially more trauma exposure. Nonetheless, this modulation was minimal and did not have an important impact on the differences of trauma exposure between immigrants and locals.

There are several hypotheses that support the association between psychological trauma and psychosis. The neurobiological explanation suggests that the hyperactivity and sensitization of hypothalamic–pituitary–adrenal (HPA) axis may result in an increase in dopamine neurotransmission mediated by stress-related glucocorticoids (Ayesa-Arriola et al., 2020; Rosenfield et al., 2022; Ruby et al., 2014). On the other hand, a psychological hypothesis supports the idea that dissociation, emotional dysregulation, cognitive negative schemata, and PTSD symptoms such as avoidance, numbing and hyperarousal, may be psychological pathways linking developmental trauma with psychotic symptoms (Bloomfield et al., 2021). Recent meta-analysis results reveal that dissociation may contribute to the development of hallucinations through impairing an individual’s ability to differentiate internal experiences from reality (Bloomfield et al., 2021). Similarly, emotional dysregulation plays a mediating role in hallucinations and paranoia, aligning with the threat anticipation model (Berry et al., 2018; Bloomfield et al., 2021). Negative cognitive schemata, on the other hand, can foster negative beliefs about others which may lead to paranoia and delusions (Bloomfield et al., 2021; Freeman, 2016). Lastly, PTSD symptoms have been associated with hallucinations, explained by disruption of the normal encoding of emotional and perceptual information due to traumatic experiences, resulting in unprocessed, fragmented memories that are susceptible to involuntary retrieval and lead to hallucinatory symptoms (Bloomfield et al., 2021; Hardy, 2017).

Considering these hypotheses and our study results, it is crucial to assess the effectiveness of psychotherapies such as cognitive–behavioral therapy (CBT), dialectical-behavioral therapy, or mentalization-based therapy addressed at improving emotional regulation or dissociative symptoms (Pearce et al., 2017), and pharmacological treatments targeting negative emotional processing biases (Cipriani et al., 2018), to understand whether these treatments are effective in reducing psychotic symptoms in individuals with psychosis and severe trauma exposure.

Several study limitations need to be considered. Firstly, traumatic events were retrospectively assessed, which could lead to recall bias. Moreover, due to reluctance or forgetfulness, the validity and accuracy of reporting by individuals with psychotic disorders has been questioned (Susser & Widom, 2012). Likewise, due to the sensitive nature of some traumatic events, this information could be repressed or withheld. Nevertheless, we used reliable and valid self-report questionnaires long used in trauma research, which measure not only the variety but also the frequency of traumatic events. Secondly, recruitment of the sample was performed by convenience. Furthermore, instruments are typically standardized for western populations and could have limitations when applied to non-western populations due to ethnocultural diversity. We performed the assessments in English and Spanish, depending on the background of our patients. Therefore, evaluators were trained in cultural competence to amend this limitation. For the EGEP-5 scale, which does not have a validated English version, bilingual evaluators were used for translation, which could result in some internal validity limitations. However, only 35 individuals from the total sample required this translation. Next, although our sample includes individuals from diverse cultures, it is essential to consider cultural factors when interpreting and extrapolating our findings to other populations. Further research is warranted to study the generalizability of these outcomes in different cultural and migration contexts thus, avoid research ethnocentrism. Lastly, we must consider that this study is susceptible to reverse causality due to its cross-sectional design; longitudinal studies are needed to elucidate this causality.

5. Conclusions

This work highlights the high current and past trauma load of non-refugee immigrants with psychotic disorders. According to our results, when compared to native-born patients, non-refugee immigrants presented significantly higher levels of PTSD, childhood trauma, stressful events in the last year, and lifetime cumulative trauma. Our results contribute to current research by providing empirical evidence to identify trauma burden in immigrants with psychotic disorders. This study has clinically relevant implications, considering the important increase in immigrants due to different worldwide humanitarian crises and the alarming risk of psychosis described in this population. Therefore, trauma-informed interventions based on cultural understanding and sensitivity, as well as humane immigration policies, are imperative to minimize distress among migrants with psychotic disorder and to ensure more accurate assessments and treatments for this population.

Supplementary Material

Supplemental Material
Click here for additional data file. (12.9KB, docx)

Acknowledgements

We are grateful to all participants in this study. AMA wants to thank also to the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement (2017 SGR 46 to Unitat de Recerca del Centre Fòrum), Generalitat de Catalunya for the recognition as an Emerging Research Group. B.L. Amann received a mobility grant (BA21/00002) from the Instituto de Salud Carlos III-Subdirección General de Evaluación y Fomento de la Investigación, Plan Nacional 2008–2011 and 2013–2016. We also acknowledge the continuous support by the CIBERSAM, Instituto Carlos III, Madrid, Spain.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available on request from the corresponding author, [A.M.], upon reasonable request. The data are not publicly available due to containing information that could compromise the privacy of research participants.

References

  1. Aas, M., Andreassen, O. A., Aminoff, S. R., Færden, A., Romm, K. L., Nesvåg, R., Berg, A. O., Simonsen, C., Agartz, I., & Melle, I. (2016). A history of childhood trauma is associated with slower improvement rates: Findings from a one-year follow-up study of patients with a first-episode psychosis. BMC Psychiatry, 16(1), 126. 10.1186/s12888-016-0827-4 [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Achim, A. M., Maziade, M., Raymond, E., Olivier, D., Merette, C., & Roy, M.-A. (2011). How prevalent are anxiety disorders in schizophrenia? A meta-analysis and critical review on a significant association. Schizophrenia Bulletin, 37(4), 811–821. 10.1093/schbul/sbp148 [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Amiri, S. (2022). Global prevalence of anxiety and PTSD in immigrants: A systematic review and meta-analysis. Neuropsychiatrie, 36(2), 69–88. 10.1007/s40211-022-00411-6 [DOI] [PubMed] [Google Scholar]
  4. Ayesa-Arriola, R., Setién-Suero, E., Marques-Feixa, L., Neergaard, K., Butjosa, A., Vázquez-Bourgon, J., Fañanás, L., & Crespo-Facorro, B. (2020). The synergetic effect of childhood trauma and recent stressful events in psychosis: Associated neurocognitive dysfunction. Acta Psychiatrica Scandinavica, 141(1), 43–51. 10.1111/acps.13114 [DOI] [PubMed] [Google Scholar]
  5. Bernstein, D. P., Fink, L., Handelsman, L., Foote, J., Lovejoy, M., Wenzel, K., Sapareto, E., & Ruggiero, J. (1994). Initial reliability and validity of a new retrospective measure of child abuse and neglect. American Journal of Psychiatry, 151(8), 1132–1136. 10.1176/ajp.151.8.1132 [DOI] [PubMed] [Google Scholar]
  6. Berry, K., Fleming, P., Wong, S., & Bucci, S. (2018). Associations between trauma, dissociation, adult attachment and proneness to hallucinations. Behavioural and Cognitive Psychotherapy, 46(3), 292–301. 10.1017/S1352465817000716 [DOI] [PubMed] [Google Scholar]
  7. Betancourt, J. R., Green, A. R., Carrillo, J. E., & Ananeh-Firempong, O. (2003). Defining cultural competence: A practical framework for addressing racial/ethnic disparities in health and health care. Public Health Reports, 118(4), 293–302. 10.1016/S0033-3549(04)50253-4 [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Bhui, K., Warfa, N., Edonya, P., McKenzie, K., & Bhugra, D. (2007). Cultural competence in mental health care: A review of model evaluations. BMC Health Services Research, 7(1), 15. 10.1186/1472-6963-7-15 [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Blasco-Fontecilla, H., Delgado-Gomez, D., Legido-Gil, T., de Leon, J., Perez-Rodriguez, M. M., & Baca-Garcia, E. (2012). Can the Holmes-Rahe social readjustment rating scale (SRRS) be used as a suicide risk scale? An exploratory study. Archives of Suicide Research, 16(1), 13–28. 10.1080/13811118.2012.640616 [DOI] [PubMed] [Google Scholar]
  10. Bloomfield, M. A. P., Chang, T., Woodl, M. J., Lyons, L. M., Cheng, Z., Bauer-Staeb, C., Hobbs, C., Bracke, S., Kennerley, H., Isham, L., Brewin, C., Billings, J., Greene, T., & Lewis, G. (2021). Psychological processes mediating the association between developmental trauma and specific psychotic symptoms in adults: A systematic review and meta-analysis. World Psychiatry, 20(1), 107–123. 10.1002/wps.20841 [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Bourque, F., van der Ven, E., & Malla, A. (2011). A meta-analysis of the risk for psychotic disorders among first- and second-generation immigrants. Psychological Medicine, 41(5), 897–910. 10.1017/S0033291710001406 [DOI] [PubMed] [Google Scholar]
  12. Boykin, D. M., Dunn, Q. T., & Orcutt, H. K. (2020). Cumulative trauma and adjustment in women exposed to a campus shooting: Examining the role of appraisals and social support. Journal of Interpersonal Violence, 35(17–18), 3601–3621. 10.1177/0886260517710483 [DOI] [PubMed] [Google Scholar]
  13. Bustamante, L. H. U., Cerqueira, R. O., Leclerc, E., & Brietzke, E. (2018). Stress, trauma, and posttraumatic stress disorder in migrants: A comprehensive review. Revista Brasileira de Psiquiatria, 40(2), 220–225. 10.1590/1516-4446-2017-2290 [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Cantor-Graae, E., & Selten, J.-P. (2005). Schizophrenia and migration: A meta-analysis and review. American Journal of Psychiatry, 162(1), 12–24. 10.1176/appi.ajp.162.1.12 [DOI] [PubMed] [Google Scholar]
  15. Cipriani, A., Williams, T., Nikolakopoulou, A., Salanti, G., Chaimani, A., Ipser, J., Cowen, P. J., Geddes, J. R., & Stein, D. J. (2018). Comparative efficacy and acceptability of pharmacological treatments for post-traumatic stress disorder in adults: A network meta-analysis. Psychological Medicine, 48(12), 1975–1984. 10.1017/S003329171700349X [DOI] [PubMed] [Google Scholar]
  16. Cougle, J. R., Resnick, H., & Kilpatrick, D. G. (2009). Does prior exposure to interpersonal violence increase risk of PTSD following subsequent exposure? Behaviour Research and Therapy, 47(12), 1012–1017. 10.1016/j.brat.2009.07.014 [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Crespo, M., & Gómez, M. M. (2012). La Evaluación del Estrés Postraumático: Presentación de la Escala de Evaluación Global de Estrés Postraumático (EGEP). Clínica y Salud, 23(1), 25–41. 10.5093/cl2012a4 [DOI] [Google Scholar]
  18. de Rivera, G., Revuelta, J. L., & Morera Fumero, A. (1983). La valoración de sucesos vitales: Adaptación española de la escala de Holmes y Rahe. Psiquis, 4(1), 7–11. [Google Scholar]
  19. Díez, A., & Sobradiel, N. (2010). Differences in the diagnosis and treatment of immigrant and local psychiatric inpatients admitted to a general hospital in Spain: A controlled study. Actas Espanolas de Psiquiatria, 38(5), 262–269. [PubMed] [Google Scholar]
  20. Eisenman, D. P., Gelberg, L., Liu, H., & Shapiro, M. F. (2003). Mental health and health-related quality of life among adult Latino primary care patients living in the United States with previous exposure to political violence. JAMA, 290(5), 627–634. 10.1001/jama.290.5.627 [DOI] [PubMed] [Google Scholar]
  21. Fan, X., Henderson, D. C., Nguyen, D. D., Cather, C., Freudenreich, O., Evins, A. E., Borba, C. P., & Goff, D. C. (2008). Posttraumatic stress disorder, cognitive function and quality of life in patients with schizophrenia. Psychiatry Research, 159(1–2), 140–146. 10.1016/j.psychres.2007.10.012 [DOI] [PubMed] [Google Scholar]
  22. Folstein, M. F., Folstein, S. E., & McHugh, P. R. (1975). ‘Mini-mental state’. A practical method for grading the cognitive state of patients for the clinician. Journal of Psychiatric Research, 12(3), 189–198. 10.1016/0022-3956(75)90026-6 [DOI] [PubMed] [Google Scholar]
  23. Fortuna, L. R., Porche, M. V., & Alegria, M. (2008). Political violence, psychosocial trauma, and the context of mental health services use among immigrant Latinos in the United States. Ethnicity & Health, 13(5), 435–463. 10.1080/13557850701837286 [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Freeman, D. (2016). Persecutory delusions: A cognitive perspective on understanding and treatment. The Lancet Psychiatry, 3(7), 685–692. 10.1016/S2215-0366(16)00066-3 [DOI] [PubMed] [Google Scholar]
  25. Garcini, L. M., Peña, J. M., Gutierrez, A. P., Fagundes, C. P., Lemus, H., Lindsay, S., & Klonoff, E. A. (2017). ‘One scar Too many’: The associations between traumatic events and psychological distress among undocumented Mexican immigrants. Journal of Traumatic Stress, 30(5), 453–462. 10.1002/jts.22216 [DOI] [PubMed] [Google Scholar]
  26. Gatt, J. M., Alexander, R., Emond, A., Foster, K., Hadfield, K., Mason-Jones, A., Reid, S., Theron, L., Ungar, M., Wouldes, T. A., & Wu, Q. (2019). Trauma, resilience, and mental health in migrant and non-migrant youth: An international cross-sectional study across six countries. Frontiers in Psychiatry, 10, 997. 10.3389/fpsyt.2019.00997 [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Gong, F., Xu, J., Fujishiro, K., & Takeuchi, D. T. (2011). A life course perspective on migration and mental health among Asian immigrants: The role of human agency. Social Science & Medicine, 73(11), 1618–1626. 10.1016/j.socscimed.2011.09.014 [DOI] [PubMed] [Google Scholar]
  28. Hardy, A. (2017). Pathways from trauma to psychotic experiences: A theoretically informed model of posttraumatic stress in psychosis. Frontiers in Psychology, 8, 697. 10.3389/fpsyg.2017.00697 [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Hernandez, A., Gallardo-Pujol, D., Pereda, N., Arntz, A., Bernstein, D. P., Gaviria, A. M., Labad, A., Valero, J., & Gutiérrez-Zotes, J. A. (2013). Initial validation of the Spanish childhood trauma questionnaire-short form: Factor structure, reliability and association with parenting. Journal of Interpersonal Violence, 28(7), 1498–1518. 10.1177/0886260512468240 [DOI] [PubMed] [Google Scholar]
  30. Hogg, B., Gardoki-Souto, I., Valiente-Gómez, A., Ribeiro Rosa, A., Fortea, L., Radua, J., Amann, B. L., & Moreno-Alcázar, A. (2022). Psychological trauma as a transdiagnostic risk factor for mental disorders: an umbrella meta-analysis. European Archives of Psychiatry and Clinical Neurocience, 273(2), 397–410. 10.1007/s00406-022-01495-5 [DOI] [PubMed] [Google Scholar]
  31. Holmes, T. H., & Rahe, R. H. (1967). The social readjustment rating scale. Journal of Psychosomatic Research, 11(2), 213–218. 10.1016/0022-3999(67)90010-4 [DOI] [PubMed] [Google Scholar]
  32. Kay, S. R., Fiszbein, A., & Opler, L. A. (1987). The Positive and Negative Syndrome Scale (PANSS) for schizophrenia. Schizophrenia Bulletin, 13(2), 261–276. 10.1093/schbul/13.2.261 [DOI] [PubMed] [Google Scholar]
  33. Kieseppä, V., Jokela, M., Holm, M., Suvisaari, J., Gissler, M., & Lehti, V. (2021). Post-traumatic stress disorder among immigrants living in Finland: Comorbidity and mental health service use. Psychiatry Research, 300, Article 113940. 10.1016/j.psychres.2021.113940 [DOI] [PubMed] [Google Scholar]
  34. Kilcommons, A. M., & Morrison, A. P. (2005). Relationships between trauma and psychosis: An exploration of cognitive and dissociative factors. Acta Psychiatrica Scandinavica, 112(5), 351–359. 10.1111/j.1600-0447.2005.00623.x [DOI] [PubMed] [Google Scholar]
  35. Kira, I. A., Lewandowski, L., Templin, T., Ramaswamy, V., Ozkan, B., & Mohanesh, J. (2008). Measuring cumulative trauma dose, types, and profiles using a development-based taxonomy of traumas. Traumatology, 14(2), 62–87. [Google Scholar]
  36. Levine, S. Z., Levav, I., Yoffe, R., & Pugachova, I. (2014). The effects of pre-natal-, early-life- and indirectly-initiated exposures to maximum adversities on the course of schizophrenia. Schizophrenia Research, 158(1–3), 236–240. 10.1016/j.schres.2014.07.003 [DOI] [PubMed] [Google Scholar]
  37. Llamas-Velasco, S., Llorente-Ayuso, L., Contador, I., & Bermejo-Pareja, F. (2015). Spanish versions of the minimental state examination (MMSE). Questions for their use in clinical practice. Revista de Neurologia, 61(8), 363–371. [PubMed] [Google Scholar]
  38. Lu, W., Mueser, K. T., Shami, A., Siglag, M., Petrides, G., Schoepp, E., Putts, M., & Saltz, J. (2011). Post-traumatic reactions to psychosis in people with multiple psychotic episodes. Schizophrenia Research, 127(1–3), 66–75. 10.1016/j.schres.2011.01.006 [DOI] [PubMed] [Google Scholar]
  39. Marrugat, J., & Vila, J. A. (2012). Sample size and power calculator 7.2. Institut Municipal d’Investigació Mèdica. [Google Scholar]
  40. Martín, V. P., & Zorita, M. J. X. (1994). Validation of Positive and Negative Symptom Scale (PANSS) in a sample of Spanish schizophrenic patients. Actas Luso-espanolas De Neurologia, Psiquiatria Y Ciencias Afines, 22(4), 171–177. [PubMed] [Google Scholar]
  41. Morgan, C., Gayer-Anderson, C., Beards, S., Hubbard, K., Mondelli, V., Di Forti, M., Murray, R. M., Pariante, C., Dazzan, P., Craig, T. J., Reininghaus, U., & Fisher, H. L. (2020). Threat, hostility and violence in childhood and later psychotic disorder: Population-based case-control study. The British Journal of Psychiatry, 217(4), 575–582. 10.1192/bjp.2020.133 [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Mueser, K. T., Goodman, L. B., Trumbetta, S. L., Rosenberg, S. D., Osher, F. C., Vidaver, R., Auciello, P., & Foy, D. W. (1998). Trauma and posttraumatic stress disorder in severe mental illness. Journal of Consulting and Clinical Psychology, 66(3), 493–499. 10.1037/0022-006X.66.3.493 [DOI] [PubMed] [Google Scholar]
  43. Myers, H. F., Wyatt, G. E., Ullman, J. B., Loeb, T. B., Chin, D., Prause, N., Zhang, M., Williams, J. K., Slavich, G. M., & Liu, H. (2015). Cumulative burden of lifetime adversities: Trauma and mental health in low-SES African Americans and Latino/as. Psychological Trauma: Theory, Research, Practice, and Policy, 7(3), 243–251. 10.1037/a0039077 [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Oram, S., Khalifeh, H., & Howard, L. M. (2017). Violence against women and mental health. The Lancet Psychiatry, 4(2), 159–170. 10.1016/S2215-0366(16)30261-9 [DOI] [PubMed] [Google Scholar]
  45. Pearce, J., Simpson, J., Berry, K., Bucci, S., Moskowitz, A., & Varese, F. (2017). Attachment and dissociation as mediators of the link between childhood trauma and psychotic experiences. Clinical Psychology & Psychotherapy, 24(6), 1304–1312. 10.1002/cpp.2100 [DOI] [PubMed] [Google Scholar]
  46. Rahe, R. H., Mahan, J. L., & Arthur, R. J. (1970). Prediction of near-future health change from subjects’ preceding life changes. Journal of Psychosomatic Research, 14(4), 401–406. 10.1016/0022-3999(70)90008-5 [DOI] [PubMed] [Google Scholar]
  47. Rasmussen, A., Crager, M., Baser, R. E., Chu, T., & Gany, F. (2012). Onset of posttraumatic stress disorder and major depression among refugees and voluntary migrants to the United States. Journal of Traumatic Stress, 25(6), 705–712. 10.1002/jts.21763 [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Resnick, S. G., Bond, G. R., & Mueser, K. T. (2003). Trauma and posttraumatic stress disorder in people with schizophrenia. Journal of Abnormal Psychology, 112(3), 415–423. 10.1037/0021-843X.112.3.415 [DOI] [PubMed] [Google Scholar]
  49. Robles, M. E., Badosa, J. M., Roig, A., Pina, B., & Feixas i Viaplana, G. (2009). La evaluación del estrés y del trauma: presentación de la versión española de la escala de trauma acumulativo (cts). Revista de Psicoterapia, 20(80), 89–104. 10.33898/rdp.v20i80.841. https://ojs.revistadepsicoterapia.com/index.php/rdp/article/view/841. [DOI] [Google Scholar]
  50. Rosenfield, P. J., Jiang, D., & Pauselli, L. (2022). Childhood adversity and psychotic disorders: Epidemiological evidence, theoretical models and clinical considerations. Schizophrenia Research, 247, 55–66. 10.1016/j.schres.2021.06.005 [DOI] [PubMed] [Google Scholar]
  51. Ruby, E., Polito, S., McMahon, K., Gorovitz, M., Corcoran, C., & Malaspina, D. (2014). Pathways associating childhood trauma to the neurobiology of schizophrenia. Psychology and Behavioral Sciences, 3(1), 1–17. 10.11648/j.pbs.20140301.11 [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Sangalang, C. C., Becerra, D., Mitchell, F. M., Lechuga-Peña, S., Lopez, K., & Kim, I. (2018). Trauma, post-migration stress, and mental health : A comparative analysis of refugees and immigrants in the United States. Journal of Immigrant and Minority Health, 21, 909–919. 10.1007/s10903-018-0826-2 [DOI] [PubMed] [Google Scholar]
  53. Selten, J.-P., van der Ven, E., & Termorshuizen, F. (2019). Migration and psychosis: A meta-analysis of incidence studies. Psychological Medicine, 50(2), 303–313. 10.1017/S0033291719000035 [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Shalev, A., Liberzon, I., & Marmar, C. (2017). Post-traumatic stress disorder. New England Journal of Medicine, 376(25), 2459–2469. 10.1056/NEJMra1612499 [DOI] [PubMed] [Google Scholar]
  55. Sideli, L., Murray, R. M., Schimmenti, A., Corso, M., La Barbera, D., Trotta, A., & Fisher, H. L. (2020). Childhood adversity and psychosis: A systematic review of bio-psycho-social mediators and moderators. Psychological Medicine, 50(11), 1761–1782. 10.1017/S0033291720002172 [DOI] [PubMed] [Google Scholar]
  56. Steel, C., Haddock, G., Tarrier, N., Picken, A., & Barrowclough, C. (2011). Auditory hallucinations and posttraumatic stress disorder within schizophrenia and substance abuse. Journal of Nervous & Mental Disease, 199(9), 709–711. 10.1097/NMD.0b013e318229d6e8 [DOI] [PubMed] [Google Scholar]
  57. Steel, J. L., Dunlavy, A. C., Harding, C. E., & Theorell, T. (2017). The psychological consequences of pre-emigration trauma and post-migration stress in refugees and immigrants from Africa. Journal of Immigrant and Minority Health, 19(3), 523–532. 10.1007/s10903-016-0478-z [DOI] [PubMed] [Google Scholar]
  58. Stilo, S. A., Gayer-Anderson, C., Beards, S., Hubbard, K., Onyejiaka, A., Keraite, A., Borges, S., Mondelli, V., Dazzan, P., Pariante, C., Di Forti, M., Murray, R. M., & Morgan, C. (2017). Further evidence of a cumulative effect of social disadvantage on risk of psychosis. Psychological Medicine, 47(5), 913–924. 10.1017/S0033291716002993 [DOI] [PMC free article] [PubMed] [Google Scholar]
  59. Stuart, J., & Nowosad, J. (2020). The influence of premigration trauma exposure and early postmigration stressors on changes in mental health over time among refugees in Australia. Journal of Traumatic Stress, 33(6), 917–927. 10.1002/jts.22586 [DOI] [PubMed] [Google Scholar]
  60. Susser, E., & Widom, C. S. (2012). Still searching for lost truths about the bitter sorrows of childhood. Schizophrenia Bulletin, 38(4), 672–675. 10.1093/schbul/sbs074 [DOI] [PMC free article] [PubMed] [Google Scholar]
  61. Tarricone, I., D'Andrea, G., Jongsma, H. E., Tosato, S., Gayer-Anderson, C., Stilo, S. A., Suprani, F., Iyegbe, C., van der Ven, E., Quattrone, D., di Forti, M., Velthorst, E., Rossi Menezes, P., Arango, C., Parellada, M., Lasalvia, A., La Cascia, C., Ferraro, L., Bobes, J., … Morgan, C. (2022). Migration history and risk of psychosis: Results from the multinational EU-GEI study. Psychological Medicine, 52(14), 2972–2984. 10.1017/S003329172000495X [DOI] [PMC free article] [PubMed] [Google Scholar]
  62. The International Organization for Migration (IOM)-United Nations . (2020). Data portal. https://www.un.org/development/desa/pd/content/international-migrant-stock
  63. Trabsa, A., Lee, N., & Lee, J. H. (2022). Posttraumatic stress symptoms, physical illness, and social adjustment among disaster victims. Disaster Medicine and Public Health Preparedness, 17, 1–7. [DOI] [PubMed] [Google Scholar]
  64. UNHCR-The UN Refugee Agency . (2020). Global trends in forced displacement – 2020.
  65. United Nations . (2020). International migrant stock. https://www.migrationdataportal.org/international-data?i=stock_abs_&t=2020.
  66. Varese, F., Smeets, F., Drukker, M., Lieverse, R., Lataster, T., Viechtbauer, W., Read, J., van Os, J., & Bentall, R. P. (2012). Childhood adversities increase the risk of psychosis: A meta-analysis of patient-control, prospective- and cross-sectional cohort studies. Schizophrenia Bulletin, 38(4), 661–671. 10.1093/schbul/sbs050 [DOI] [PMC free article] [PubMed] [Google Scholar]
  67. Wilson, F. E., Hennessy, E., Dooley, B., Kelly, B. D., & Ryan, D. A. (2013). Trauma and PTSD rates in an Irish psychiatric population. Disaster Health, 1(2), 74–83. 10.4161/dish.27366 [DOI] [PMC free article] [PubMed] [Google Scholar]
  68. WMA . (2022). WMA declaration of Helsinki – ethical principles for medical research involving human subjects. https://www.wma.net/policies-post/wma-declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects/ [PubMed]
  69. World Health Organization . (2021). Mental health and forced displacement. https://www.who.int/news-room/fact-sheets/detail/mental-health-and-forced-displacement

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supplemental Material
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Data Availability Statement

The data that support the findings of this study are available on request from the corresponding author, [A.M.], upon reasonable request. The data are not publicly available due to containing information that could compromise the privacy of research participants.

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