Immigration as risk factor for non-suicidal self-injury and suicide attempts in adolescents in Germany

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.