L Mustelin1,2,3, A M Hedman4, L M Thornton1, R Kuja-Halkola4, A Keski-Rahkonen2, E Cantor-Graae5, C Almqvist4, A Birgegård6, P Lichtenstein4, P B Mortensen7,8,9, C B Pedersen7,8,9, C M Bulik1,4. 1. Departments of Psychiatry and Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. 2. Department of Public Health, University of Helsinki, Helsinki, Finland. 3. Institute for Molecular Medicine Finland FIMM, University of Helsinki, Helsinki, Finland. 4. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. 5. Social Medicine and Global Health, Lund University, Malmö, Sweden. 6. Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden. 7. National Centre for Register-based Research, School of Business and Social Sciences, Aarhus University, Aarhus, Denmark. 8. Centre for Integrated Register-based Research, CIRRAU, Aarhus University, Aarhus, Denmark. 9. The Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus, Denmark.
Abstract
OBJECTIVE: The risk of certain psychiatric disorders is elevated among immigrants. To date, no population studies on immigrant health have addressed eating disorders. We examined whether risk of eating disorders in first- and second-generation immigrants differs from native-born Danes and Swedes. METHOD: All individuals born 1984-2002 (Danish cohort) and 1989-1999 (Swedish cohort) and residing in the respective country on their 10th birthday were included. They were followed up for the development of eating disorders based on out-patient and in-patient data. RESULTS: The risks of all eating disorder types were lower among first-generation immigrants compared to the native populations: Incidence-rate ratio (95% confidence interval) was 0.39 (0.29, 0.51) for anorexia nervosa, 0.60 (0.42, 0.83) for bulimia nervosa, and 0.62 (0.47, 0.79) for other eating disorders in Denmark and 0.27 (0.21, 0.34) for anorexia nervosa, 0.30 (0.18, 0.51) for bulimia nervosa, and 0.39 (0.32, 0.47) for other eating disorders in Sweden. Likewise, second-generation immigrants by both parents were at lower risk, whereas those with only one foreign-born parent were not. CONCLUSION: The decreased risk of eating disorders among immigrants is opposite to what has been observed for other psychiatric disorders, particularly schizophrenia. Possible explanations include buffering sociocultural factors and underdetection in health care.
OBJECTIVE: The risk of certain psychiatric disorders is elevated among immigrants. To date, no population studies on immigrant health have addressed eating disorders. We examined whether risk of eating disorders in first- and second-generation immigrants differs from native-born Danes and Swedes. METHOD: All individuals born 1984-2002 (Danish cohort) and 1989-1999 (Swedish cohort) and residing in the respective country on their 10th birthday were included. They were followed up for the development of eating disorders based on out-patient and in-patient data. RESULTS: The risks of all eating disorder types were lower among first-generation immigrants compared to the native populations: Incidence-rate ratio (95% confidence interval) was 0.39 (0.29, 0.51) for anorexia nervosa, 0.60 (0.42, 0.83) for bulimia nervosa, and 0.62 (0.47, 0.79) for other eating disorders in Denmark and 0.27 (0.21, 0.34) for anorexia nervosa, 0.30 (0.18, 0.51) for bulimia nervosa, and 0.39 (0.32, 0.47) for other eating disorders in Sweden. Likewise, second-generation immigrants by both parents were at lower risk, whereas those with only one foreign-born parent were not. CONCLUSION: The decreased risk of eating disorders among immigrants is opposite to what has been observed for other psychiatric disorders, particularly schizophrenia. Possible explanations include buffering sociocultural factors and underdetection in health care.