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Terrorism in the country of origin is linked to deterioration in the mental health of refugees


Refugees flee their country of origin to escape threats to their existence. Yet, despite having left behind the immediate physical dangers in their country of origin, refugees may continue to experience negative psychological consequences of contemporary violence in that country because of their connection to it. Here, using longitudinal population data from Denmark, we show that refugees were substantially more likely to use antidepressants, and anxiolytic and hypnotic drugs in periods when their country of origin was more intensely afflicted by terrorism. The finding that contemporary terrorism in the home country is negatively associated with the mental health of refugees highlights the potential vulnerability of such groups and points to the need to identify the extended global consequences of terrorism.

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Fig. 1: Average share of refugees using psychotropic drugs within a given year between 1998 and 2012 by country of origin.
Fig. 2: Total number of casualties per year for selected countries with high levels of terrorism.
Fig. 3: The average yearly number of terrorism-induced casualties for the countries that experienced the highest levels of terrorism during 1998–2012.
Fig. 4: Psychotropic drug use among refugees and casualties from terrorism in their country of origin.

Data availability

The data regarding terrorism is freely available from the Global Terrorism Database ( The individual-level data contains information that may enable identification of individuals. Therefore, the dataset cannot be made publicly available. To acquire access to the data used in this study, researchers must apply for permission from the Danish National Board of Health ( and Statistics Denmark (, and register the study at the Danish Data Protection Agency ( Only researchers affiliated with institutions approved by Statistics Denmark can access the data via their remote access system.

Code availability

The code to reproduce all results reported in the manuscript is available on request.


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We thank participants at the annual conference of the Danish Political Science Association, at the Oslo Workshop on Subnational and Historical Dimensions of Conflict, and at a seminar in the Department of Political Science, University College London for insightful feedback and helpful comments. We also thank F. J. Jørgensen for research assistance. This research was supported by The Carlsberg Foundation, grants CF11-0609 (to P.T.D.) and CF14-0703 (to K.M.S.). The funder had no role in the study design, in the collection, analysis, and interpretation of data, in the writing of the report, or in the decision to submit the paper for publication.

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The data for this study were acquired by K.M.S., P.T.D. and S.D.Ø. All authors contributed to the design of the study. The analyses were conducted by K.M.S., B.D. and B.T.H. All authors contributed to the interpretation of the results. The manuscript was drafted and revised by P.T.D. and K.M.S. with contributions from all other authors. The final version of the manuscript was approved by all authors prior to submission.

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Correspondence to Kim M. Sønderskov.

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The authors declare no competing interests.

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Peer review information Nature Human Behaviour thanks Domenico Giacco, David Laitin and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Sønderskov, K.M., Dinesen, P.T., Hansen, B.T. et al. Terrorism in the country of origin is linked to deterioration in the mental health of refugees. Nat Hum Behav (2021).

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