Our findings indicate that individual-level immigrant status was a risk factor for mental health problems among immigrant adolescents in Sweden from 1995 to 2011. However, the time trends in mental health problems did not differ between immigrant and native adolescents. Furthermore, the gap in mental health problems between immigrant and native adolescents did not differ according to the municipality-level proportion of immigrant students.
Mental Health Among Immigrant and Native Adolescents
Immigrant adolescents presented a higher degree of mental health problems than native adolescents. Thus, between the two competing hypotheses on immigrant adolescents’ mental health in comparison to their native peers of worse versus the same or better, our finding supports the former. This indicates a need for public health attention to the mental health of immigrant adolescents in Sweden who, despite their poorer mental health than natives, do not necessarily seek and receive more treatment [16].
Consistent with Stevens and Vollebergh [5] ’s evaluation, the difference in mental health problems between immigrant and native adolescents remained significant after accounting for the effects of economic situation, a potential confounder for worse mental health among immigrant populations. This indicates that economic reasons may not underlie the mental health gap between immigrant and native adolescents in Sweden. Once immigrants are settled in the host society, other factors besides economic factors may contribute to their adjustment [33]. Two non-economic considerations are relevant to the Swedish context that may contribute to the mental health gap between immigrant and native adolescents.
The first concerns migration-related factors that may be disadvantageous to immigrant adolescents’ mental health in the long run. Kirmayer et al. [34] exemplified such factors that include exposures to traumatic experiences and harsh living conditions and separation from significant others. These indeed are relevant to the current study as most immigrants in Sweden consist of refugees, asylum seekers, and/or unskilled labor workers [5]. We suggest that other European studies indicating poorer mental health among immigrant adolescents compared to native peers e.g., [4, 6,7,8] may share this underlying reason to some degree.
The second consideration concerns the social climate that reflects, and is reflected in, attitudes and government policies toward immigrants in the host society. Favorable attitudes towards immigrants and integration-orientated policies in the host society usually have positive implications for mental health among immigrants [33, 35, 36]. Thus, our observation of poorer mental health among immigrant adolescents compared to natives was unexpected given that the Swedish society has maintained an accepting atmosphere and favorable attitudes towards immigrants [37, 38]. However, it has also been suggested that Swedish society is majority-oriented, which may structurally burden immigrant adolescents and affect their mental health [17].
Time Trends in Mental Health Problems Between Immigrant and Native Adolescents
Given potentially distinctive impacts of societal changes on the mental health of different groups, previous studies explored the time trends in adolescent mental health according to gender, age, socio-economic status, and family structure [20, 22, 29, 39]. To our knowledge, this is the first study that empirically tested whether the time trends in mental health problems differed according to immigrant status in Sweden. Our evidence indicates that the increased trend of mental health problems among Swedish adolescents held for both immigrant and native adolescents.
Although statistically not significant, the descriptive pattern (Fig. 2) suggests that, whereas mental health problems decreased from 2005 onwards among native adolescents, mental health problems continued to increase among immigrant adolescents. Immigration has become an increasingly important issue after our last investigation year (i.e., 2011) and, since 2015, has been ranked as the social issue of the utmost importance among EU member states [40]. Clearly, the trends in mental health after our investigation period require further investigation.
Proportion of Immigrants in the Surrounding Community
In this study, the association between immigrant status and adolescents’ mental health did not differ according to the proportion of immigrant adolescents in their community. That is, immigrant adolescents’ mental health was not more favorable when living in municipalities in which more adolescents had an immigration background. This is consistent with a previous study that reported no significant interaction between individual-level immigrant status and the proportion of immigrant students in the classroom in predicting mental health [26].
Perhaps, the positive influences of increasing immigrant populations in the community extend only to some areas of adolescents’ lives that are related to mental health problems such as peer popularity [26] but not to mental health problems directly. Similarly, a recent Swedish study using registered population data reported that immigrant adolescents’ educational outcomes were not much benefited from higher proportions of immigrant classmates [41]. Another possibility is that any positive influences may have been offset by other negative, counteracting influences. As the Swedish immigrant population continued to grow during the entire investigation period, social resistance may have co-arisen to some degree, cancelling out positive influences of increasing immigrant populations on individual immigrants. These are only speculations of ours and await future studies to substantiate them.