Both non-suicidal self-injury (NSSI) and suicide attempts are rather common among German adolescents. Whereas worldwide lifetime prevalence rates of NSSI between 17 and 18% were reported from systematic reviews [1, 2], studies from Germany reported a lifetime prevalence rate of 25.6% in adolescents [3], and a 6-month prevalence rate of 14.6% [4]. Using criteria proposed in section 3 of the DSM-5 for NSSI disorder [5], a retrospective data analysis described a prevalence of 4% among German adolescents [6]. Recently, a large study comparing adolescent samples from 11 European countries (including Israel) reported a lifetime prevalence rate of 27.6% of “direct self-injurious behavior” (D-SIB: combining self-harming behaviors regardless of suicidal intent). Adolescents from Germany showed the second highest prevalence rate for occasional (22.9%) and for repetitive (12.3%) D-SIB [7].
With regards to suicidal ideation and suicide attempts, a large (n = 45,806) European study reported a median lifetime prevalence rate of 10.5% for suicide attempts in adolescents, with 30.8% reporting a history of self-harm thoughts [8]. In Germany, lifetime prevalence rates of suicidal ideation in adolescents were reported to be between 14.5% [9], 36.4% [3] and 39.4% [10], with a reported 6-month prevalence rate of 3.8% [11]. A lifetime history of suicide attempts was reported to be between 6.5% [3], 7.8% [9] and 9.0% [10].
Searching for predictors of NSSI, a recent systematic review of longitudinal studies described several factors, stemming from 32 longitudinal studies [12]. Among them were female gender, a history of previous NSSI, suicide attempts or suicidal ideation, and depressive symptoms. However, migration was not described being a risk factor for NSSI in these studies, due to the fact that it had not been included as a possible risk factor in most studies. However, migration in itself might be viewed as a combination of several stressors, for example the loss of cultural connectedness, the use of another language, the adaption to new norms and lifestyles, discrimination, peer alienation and changes in the socioeconomic status (for review [13]).
Literature about migration and suicidality in adolescents is still very scarce [13]. Furthermore, most studies attempting to further explore migration status as risk factor for NSSI and suicidal behavior have been conducted in the US. Borges et al. [14] reported from two nationally representative surveys about suicidal behavior being higher for Mexican immigrants who came to the US before the age of 12, as well as for US born Mexican Americans. Furthermore, the risk for suicide attempts nearly doubled (OR 1.97) for US born Mexican Americans. Interestingly, in a study on Boston youth, Borges et al. [15] described adolescents with a migration background not to be at higher risk for NSSI and suicidal ideation than US born youth. However, being discriminated due to one’s ancestry increased the risk of NSSI (OR 3.1) and suicidal ideation (OR 2.1) in US born youth with a background of migration. The authors of the study argued, that a dissonance between being born in a country and yet not being perceived as fully integrated could create a distress in these youths [15]. In addition, it was shown that US-born Latino adolescents were 2.87 times more likely to attempt suicide as Latino youth born in another country (i.e. first-generation youth). Third generation Latino youth (with US born parents) were even 3.57 times more likely to attempt suicide than first generation Latino adolescents [16]. Contrary to these findings, differences in rates of suicide attempts between different ethnic groups in a large (N = 15,180) US based Collaborative Psychiatric Epidemiological survey vanished to exist after adjusting for psychiatric disorders [17]. A Canadian study looking into suicides in youth between the age of 15 and 24, showed that immigrants´ suicide death rate was lower than the death rate of Canadian youth [18].
A European perspective has been reported based on data from the WHO/EURO Multicentre Study on Suicidal Behaviour, in which suicide attempt rates of adults were compared among 25 European centers. Overall, suicide attempt rates were higher in participants with a migration background when compared to the population of their host country. There was a strong correlation between suicide attempt rates among immigrants and suicide rates in their countries of origin (with the exception of Chileans, Turks, Ukrainians and Iranians) [19].
In a large Swedish study of 10,018 young adults between the ages of 18 and 29, non-European females with a migration background showed a higher rate of suicide attempts than their Swedish counterparts, which was especially pronounced in first generation non-European females (OR 3.52) in comparison to second-generation females with a migration background (OR 1.60) [20]. In another Swedish study of more than a million children, who were followed up prospectively, youth with both parents being born outside of Sweden showed higher rates of self-harm. However, these differences diminished after adjusting for socioeconomic status, but were still elevated in migrants from Finland, Western countries and children of mixed couples (one parent from Sweden, one from another country [21]). In a case–control study comparing 70 Turkish immigrants, who had attempted suicide and 70 Swiss suicide attempters, it could be shown, that the percentage of young (between the age of 15 and 25 years) Turkish women was higher than in the Swiss comparison group [22]. In addition it has been shown from a retrospective chart review of 210 children and adolescents (6–18 years of age) presenting after a suicide attempt to an Emergency Outpatient Clinic in Istanbul, that besides immigration to a foreign country, internal migration (migration from other parts of the same country with large cultural differences) also serves as a risk factor to choose a high risk method of suicide attempt [23]. High acculturation stress, along with immigration stress was also reported to be associated with a higher rate of self harming behaviors in a sample of 1,651 Hispanic adolescents [24].
Data about the association between NSSI, suicide attempts and migration background is scarcely available from adolescent samples in Germany. However, young adult women with a migration background have been shown to have elevated rates of suicide and suicide attempts [25]. A study on suicide attempts of adult women with Turkish origin in the Berlin region found high age-adjusted incidence rates of suicide attempts between 66.9 and 92.2/100,000, with highest rates in the age group from 18 to 24 [26]. One large, representative study of 44,610 adolescents showed immigration background to be a risk factor for suicide attempts, especially for adolescents from “Islamic imprinted countries” (being defined as “all countries whose culture is essentially influenced by Islamic theology” according to [10]) with an OR of 1.55 [10]. In a recent study following a cohort of 6,378 German repatriates from Russia for up to 20 years, it has been shown, that migration between the age of 11 and 20 increased the risk of committing suicide or dying from events of undetermined intent in males [27]. However, NSSI has not been assessed in these studies. Overall, migration can be viewed as under-researched risk factor for self-harming behaviors. Our aim was to specifically explore migration status as risk factor both for NSSI as well as suicide attempts. We adjusted for socioeconomic status, gender and age.