Prevalence of diabetes among immigrants in the Nordic countries.

Some immigrant groups in Europe show an increased prevalence of diabetes, e.g. South Asians in the UK and Moroccans and Turks in the Netherlands. This study aimed at reviewing the literature among immigrants in the Nordic countries. Search was performed primarily of Medline through PubMed, and secondarily of other databases and by using information from reference lists. Terms used were: "Diabetes Mellitus", "Immigrant", and "Nordic countries" or "Scandinavia" or "Denmark", "Finland", "Iceland", "Norway" or "Sweden". Altogether 17 articles on diabetes were found. Excess risk of diabetes was found in non-European immigrant groups, especially from the Middle East and South Asian regions, in some cases 10 times the risk of the indigenous population, with the highest relative risks among women. No excess risk was found among European immigrants, with the possible exception of Finnish women. Conflicting results were found in studies with a low number of diabetic cases, with a failure to show statistically significant excess risks among non-European groups. There were also some other methodological problems, e.g. low participation rate in population based clinical studies, and probable underestimation of known diabetes by self-report. A genetic sensitivity seems likely in the Middle East and South Asian groups, combined with lifestyle factors.