Mental health and resilience among Eritrean refugees at arrival and one-year post-registration in Switzerland: a cohort study

Eritrea is the most frequent country of origin among asylum seekers in Switzerland. On their journey through the desert and across the Mediterranean Sea, Eritrea refugees are often exposed to traumatizing experiences. The aim of this study is to assess the mental health status and resilience of Eritrean migrants in Switzerland upon arrival and one-year post-arrival, using standardized mental health screening and resilience assessment tools. At baseline, 107 refugees (11.2% female, median age 25) were interviewed: 52 (48.6%) screened positive for Post-Traumatic Stress Disorder (score ≥ 30), 10.3% for anxiety (≥ 10) and 15.0% for depression (≥ 10); 17.8% scored as risk/hazardous drinkers (≥ 8). The majority (94.4%) had a high resilience score (≥ 65). For one-year follow-up, 48 asylum seekers could be reached. In interviews 18 (38%) of these reported imprisonment in a transit country and 28 (58%) that they had witnessed the death of a close person along the migration route. At the one year assessment, rates of risky/hazardous alcohol use remained unchanged, rates of positive PTSD screening tended to be lower (50.0% (24/48) at baseline vs 25.0% (12/48) at follow-up), as were rates of positive screening for anxiety (8.3% vs 4.2%) and depression (14.6 vs 6.3%).


Introduction
In Switzerland, Eritreans have formed the largest group of asylum seekers for the last decade. In 2018 alone, out of the 15,255 refugees who sought asylum in the country, 18.5% were Eritreans, followed by refugees from Syria (9.1%) [1].
Many refugees from Eritrea are at risk of being exposed to mentally traumatizing events, be it in their country of origin, or during the migration journey to Europe [2,3]. Such mental trauma could potentially predispose migrants to develop mental health problems during migration, at or after arrival in their host country.
Further, several of the macro and micro root causes of migration also contribute to the wellbeing and mental health status of migrants [4]. Moreover, migration by itself is a frequent cause of impaired mental health [5].
Psychiatric problems constitute a substantial burden to migrants, both during the migration route and postmigration [6][7][8]. The prevalence of post-traumatic stress disorder (PTSD) among migrants has been reported to be 47% [9]. Médecins Sans Frontières reports that 31% and 20% of newly arrived African refugees coming from Libya and landing in Italy had PTSD and/or depression, respectively [10]. A qualitative study conducting in-depth interviews with 10 Eritrean asylum seekers and refugees in Switzerland revealed that somatic and mental health problems are often overlapping and perceived as an entity. Thus, mental health conditions may be underdiagnosed in host countries [11]. In this manuscript, we provide data from mental health screening and interviews among Eritrean asylum seekers and refugees shortly after arrival in Switzerland and at the one-year follow-up.

Methods and materials Participants
The study was conducted in refugees' centers of two cantons (canton Basel-Land and Basel-Stadt) in the northwestern part of Switzerland. Recently arrived (arrivals in 2014 and 2015) refugees and migrants from Eritrea, who were at least 16 years old and who had no major medical complaints, were invited to take part in the study. The recruitment period was from February 2016 to November 2016. Study participants were approached through the registers provided by the cantonal social assistant offices. Invitation letters written in Tigrigna (an Eritrean local language) and English were sent by mail to potential participants. Refugees and asylum seekers, who were interested in taking part in the study, were briefed on the phone, and invited to the outpatient department of the Swiss Tropical and Public Health Institute (Swiss TPH).
This study is part of a larger study that involved an extensive health check-up, including screening for infectious diseases, cardio-vascular risk factors, and mental health-related problems on arrival and at one-year follow-up. The detailed recruitment procedure and results for infectious diseases and cardio-vascular risk-factor screening have previously been described elsewhere [12]. In this manuscript, we present the data on mental health and resilience screening at arrival and one year followup. All participants provided written informed consent for enrollment.

Data collection
Interviews took place in a closed room to ensure confidentiality and were conducted in Tigrigna by the first author. Four standardized questionnaires were applied: For alcohol use, the Alcohol Use Disorders Identification Test (AUDIT) [13], with a scale from 0-40 was used. To screen for depression, anxiety and somatic problems, the Patient Health Questionnaire Somatic Anxiety and Depression Syndrome (PHQ-SADS) package was used [14]. The package is composed of Patient Health Questionnaire-15 (PHQ-15), Generalized Anxiety Disorder-7 (GAD-7), and Patient Health Questionnaire-9 (PHQ-9). The Post-Traumatic Stress Disorder Check List-Civilian Version (PTSD-CL-S) was used to screen for PTSD [15], and the 14-Item Resilience Scale (RS-14) [16,17] to measure coping and resilience ability.
One year after baseline screening, participants were contacted and invited to a follow-up assessment using the same questionnaires and interview procedures plus an additional questionnaire on experiences during migration and current status of integration in Switzerland.

Analysis
All data were collected on paper-based forms and subsequently entered into spreadsheets and EpiInfo version 7 (Centers for Disease Control and Prevention, CDC, 1600 Clifton Road Atlanta, USA) using double data entry. Continuous variables are reported as median with interquartile range (IQR); prevalence is reported as percentage with 95% confidence intervals (95%CI). Due to small numbers at follow up, analysis is descriptive. Reporting in this manuscript follows the STROBE guidelines for crosssectional studies (https:// www. strobe-state ment. org).

Ethics statement
The study protocol was reviewed and approved by the institutional research commission and ethical review board of the Swiss Tropical and Public Health Institute (Swiss TPH, Basel, Switzerland; reference no. FK 120; approval date: June 24, 2015), and the national ethics committee of Northwest and Central Switzerland (reference no. EKNZ 2015-353; approval date: November 20, 2015). Participation was voluntary, and hence, people could withdraw from the study at any time without further obligations. Data were processed anonymously.
Out of the 107 participants enrolled, 48 (45.0%) attended the one-year follow-up screening. The remaining participants had either moved to a different canton or out of Switzerland (45.0%), or declined participation in the follow-up visit (10.0%). Table 3 provides socioeconomic characteristics and reported traumatic events during the migration process from these 48 participants. The median duration of the migration journey (from Eritrea to Switzerland) was 8.5 months. Imprisonment during transit to Europe was reported by 38%, and 58% stated having witnessed the death of a close person during migration. One-year post-arrival the majority, 58% still did not have a stable residence status in Switzerland; nearly all lived from social assistance and reported a monthly net income below CHF 1000.
Additional file 1: Table S1 displays the mental health screening results at baseline and at the one-year followup in the sub-group with complete one-year follow up data (N = 48). Rates of hazardous alcohol consumption did not change substantially. There was a non-significant trend to improvement in somatic symptoms, anxiety disorder and depression. The prevalence of positive screening for PTSD halved from 50% (24/48) to 25% (12/48). Resilience scores remained high.

Discussion
This study assessed the mental health status and resilience among Eritrean migrants at arrival in Switzerland and one-year post registration. On arrival, almost half of Eritrean refugees screened positive for PTSD. Positive screenings for other mental health conditions were less frequent. Apart from alcohol use that remained unchanged, the prevalence of positive screening decreased for all other conditions at the one-year follow-up. This change was, however, not statistically significant. In general, Eritrean refugees showed high resilience scores. Interviews with participants revealed that the majority were exposed to psychological harm during their transit to Europe, i.e. imprisonment in one   In line with our findings, several studies report close to 50% prevalence of PTSD among migrants and refugees arriving in their host country. However, published studies included no or very few participants from Eritrea or East Africa [9,13,18,19]. As shown in Table 3, a high share of participants in our study has experienced psychological trauma. Similarly, a study investigating traumatic experiences of East African migrants arriving in Israel showed that 56.0 and 34.9% of men and women respectively had been victims of various forms of violence [3].
At baseline as well as one-year post registration, participants had high scores on the resilience scale (Table 2 and Additional file 1: Table S1). The high resilience may be a reason for the reduction of positive PTSD screening at one-year follow-up and the overall rather low prevalence of depression and anxiety disorder in this refugee population [20,21].
In summary, as shown in other refugee populations, our data demonstrate a high burden of mental health conditions at arrival in the host country, particularly PTSD. Further, even though we observed a tendency to improved mental health status one year post-registration, one out of four participants still screened positive for PTSD. These findings should sensitize health authorities as well as clinicians in host countries to consider screening for mental health conditions among Eritrean refugees.

Limitations
This study has several limitations, mainly the relatively small sample size of 107 participants, and only 48 participants who could be included in the one-year follow-up analysis. In addition, there is relatively low participation of female refugees. Moreover, while interpreting our findings, one must be aware that they rely on self-reporting and that the thresholds used in the applied questionnaires constitute a positive screening result but not a definite diagnosis of the respective mental health condition.