Symptom manifestation and treatment effectiveness, -obstacles and -facilitators in Turkish and Moroccan groups with depression in European countries: A systematic review

Background: This study examined the state of the art relevant for clinical practice on symptom manifestation of depression or depression-related idioms of distress, the treatment effectiveness and obstacles and facilitators for therapeutic success in Turkish and Moroccan immigrant populations with depression in Europe. Methods: We conducted a systematic search in PsycINFO, MEDLINE, Science Direct, Web of Knowledge, and Cochrane databases (1970- 31 July 2017). Peer-reviewed studies, with adult populations, and an instrument assessing depressive symptoms met inclusion criteria and were evaluated following quality guidelines. Results: We included 13 studies on symptom manifestation, 6 on treatment effectiveness, and 17 on obstacles and facilitators, published between 2000 and 2017, from Germany, the Netherlands, Austria and Sweden (n Turkish individuals = 11,533; n Moroccan individuals = 5278; n native individuals = 303,212). Both ethnic groups more often reported combined mood and somatic symptoms (and anxiety in the case of Turkish groups) than natives, and had higher levels of symptoms. There was no report on effectiveness of pharmacotherapy and there was weak evidence of the effectiveness of examined psychological treatments for depression in Turkish groups. No treatment has been examined in Moroccan groups. Salient obstacles to therapeutic success were socioeconomic problems, higher level of psychological symptoms at baseline, and negative attitudes towards psychotherapy. Possible facilitators were interventions attuned to social, cultural and individual needs. Results were most representative of first generation, low SES Turkish immigrant patients, and Moroccan-Dutch members of the general populations. Conclusion: Turkish and Moroccan immigrants with depression presented a comorbid symptom profile with more intertwined depressive and somatic complaints. There were indications that the available therapies are insufficient for Turkish groups, but the current evidence is scarce and heterogeneous, and RCTs suffer from methodological limitations.