AIMS: A number of aspects of the health status of migrants who return to their country of origin have been explored in the literature; however, a more general description of the incidence of disease and demographic characteristics is lacking. The aim of this research was to contribute such a description.

METHODS: A nationwide cohort study was conducted of 114,331 migrants who obtained residence in Denmark between 1 January 1993 and 31 December 2010. Demographic characteristics and ten disease groups were included as explanatory variables and hazards ratios for the association between return migration and disease incidence, as well as demographic characteristics, were estimated using Cox regressions.

RESULTS: The tendency to return-migrate when ill was not the same among younger and elderly migrants; migrants <55 years of age had a significantly smaller propensity to return-migrate if they had suffered from a disease during the 18 years of follow-up compared with those who had not had a disease, whereas migrants ≥55 years of age were more prone to return if ill. The likelihood of returning decreased with increasing comorbidity in both age groups. Among those who were <55 years of age, the tendency to return increased with age at obtainment of residence; among those who were ≥55 years, more men than women return-migrated.

CONCLUSIONS: In Denmark, younger migrants are less inclined to return-migrate if they are ill compared with healthy migrants, whereas elderly migrants are more inclined to return if ill. The returnees also differ demographically from non-returnees in various ways.