Study examines relationship between type 2 diabetes and depression
Posted on 30/03/2016
A new study by researchers from King’s College London examines the genetic and environmental relationship between type 2 diabetes and depression.
Previous research has consistently reported a link between the two conditions, with up to 60 per cent increased risk of type 2 diabetes in people with depression and 15 per cent increased risk for depression in those with type 2 diabetes. However, until now, the underlying mechanisms behind this association have remained unclear.
Published this week in Molecular Psychiatry, the study is the largest-ever to analyse why the two disorders sometimes occur together.
The researchers conducted genetic analyses on 160,000 twins in two Scandinavian countries (Sweden and Denmark) and found that genetic factors do appear to play a role in the relationship between type 2 diabetes and depression.
In the Swedish sample, genetic effects explained 31 per cent of the overlap between diabetes and depression in males and this increased to 75 per cent in females. When focusing on the Danish sample, the researchers found that genetic factors were most important in explaining the relationship between diabetes and depression for both men (87 per cent) and women (74 per cent).
Dr Carol Kan from the Department of Psychological Medicine at the Institute of Psychiatry, Psychology & Neuroscience (IoPPN), King’s College London, said: ‘Our study also suggests that genetic factors influencing the relationship between diabetes and depression in men are different to those affecting the relationship in women.
'These findings go some way towards explaining why diabetes and depression sometimes occur together, although further research is needed to explore the effect of gender in this interplay between genetic factors and environmental influences, such as diet and lifestyle.'
Dr Kan concluded: ‘A better understanding of the mechanisms underlying these disorders and why they sometimes exist in tandem could one day provide useful biological targets for therapeutic interventions.’
This study is based on data from the Swedish Twin Registry and Danish Twin Registry and is part of the transcampus initiative in diabetes between King's and Technische Universität Dresden.
The research was funded by Novo Nordisk UK Research Foundation and the National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) at South London and Maudsley NHS Foundation Trust and King’s College London.
Notes to editors
Paper reference: Kan, C et al (2016) Genetic overlap between type 2 diabetes and depression in Swedish and Danish twin registries Molecular Psychiatry doi: 10.1038/mp.2016.28