New research published in the online journal PLOS ONE suggests that depression raises the risk of arthritis and digestive diseases, while anxiety disorders tend to be followed by skin diseases.
The study, by the University of Basel and Ruhr University Bochum, aimed to examine the temporal pattern and relationship between physical diseases and mental disorders in young people.
The researchers analysed data from 6,483 teenagers from the US between the ages of 13 and 18. They found that affective disorders such as depression were frequently followed by arthritis and diseases of the digestive system, while the same relationship existed between anxiety disorders and skin diseases. Close associations were also observed between anxiety disorders and heart disease and, for the first time, epileptic disorders and subsequent eating disorders.
The researchers say their results offer ‘important insights’ into the causal relationship between mental disorders and physical diseases, adding that treatment of mental and physical health should be closely linked from an early age.
Marion Tegethoff, the study’s lead author, said: ‘For the first time, we have established that epilepsy is followed by an increased risk of eating disorders — a phenomenon that had previously been described only in single case reports. This suggests that approaches to epilepsy treatment could also have potential in the context of eating disorders.’
That anxiety and depression may be related to physical ailments seems intuitive. Most GPs will tell you that there is a significant overlap of the two paradigms in their caseload. This paper seeks to highlight tangible links between specific examples of the two.
A strength of the study is the large number of subjects (6,483) and the relative statistical significance of some of the relationships found. The authors considered a broad range of mental disorders and physical diseases and the methodology seems robust. However, the authors’ reliance on certain parameters limits the generalisability of the findings, namely the self-reporting of physical ailments, the cross-sectional design and the use of retrospective data.
It should also be pointed out that one of the authors is a paid consultant for a pharmaceutical company.
Research score: 3/5