title: Genetic overlap between type 2 diabetes and depression in Swedish and Danish twin registries.
abstract: A bidirectional association between type 2 diabetes (T2DM) and depression has been consistently reported. Depression is associated with worse biomedical outcomes and increased mortality. The mechanisms underlying the association of T2DM with depression remain unclear. One possible question we can address is the extent to which the co-occurrence of diabetes and depression is due to correlated genetic and/or environmental risk factors. In this study, we performed structural equation model fitting to population-level data from the Swedish (n=68 606) and Danish (n=95 403) twin registries. The primary outcomes were clinical diagnosis of T2DM and depression using national hospital discharge registries. The phenotypic correlation between T2DM and depression is modest in both samples. In the Swedish sample, unique environmental effects explain a greater proportion of the covariance in males, whereas the association is primarily attributed to genetic effects in females. In the Danish sample, genetic effects account for the majority of the covariance in both males and females. Qualitative genetic sex differences are observed in both samples. We believe this is the first study to demonstrate significant genetic overlap between T2DM and depression.
authors.affiliation: Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: C
authors.identifier: 0000-0002-2511-0682
authors.initials: C
authors.lastname: Kan
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden.
authors.forename: N L
authors.initials: NL
authors.lastname: Pedersen
authors.affiliation: The Danish Twin Registry, University of Southern Denmark, Odense, Denmark.|Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Christensen
authors.affiliation: Department of Diabetes, King's College London, London, UK.|Medical Department and Clinic III, Carl Gustav Carus University Hospital, Dresden, Germany.
authors.forename: S R
authors.initials: SR
authors.lastname: Bornstein
authors.affiliation: South Australian Health and Medical Research Institute, Adelaide, SA, Australia.|Flinders University, Adelaide, SA, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Licinio
authors.affiliation: Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: J H
authors.initials: JH
authors.lastname: MacCabe
authors.affiliation: Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.|Department of Diabetes, King's College London, London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Ismail
authors.affiliation: Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: F
authors.initials: F
authors.lastname: Rijsdijk
mesh_terms: D000328:Adult; D003718:Denmark; D003863:Depression / Q000235:genetics*; D003866:Depressive Disorder / Q000235:genetics; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D004200:Diseases in Twins / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D012307:Risk Factors; D012737:Sex Factors; D013548:Sweden; D014429:Twins, Dizygotic / Q000235:genetics; D014430:Twins, Monozygotic / Q000235:genetics