Combinations of chronic illnesses could double risk of depression

(Press-News.org) People with multiple long-term physical health conditions are at a significantly greater risk of developing depression, a study shows.  

Researchers found that some combinations of illnesses – particularly cardiometabolic ones like diabetes and heart disease – could more than double the likelihood of a future depression diagnosis.  

With multimorbidity – when patients live with two or more chronic conditions – continuing to put pressure on an already stretched healthcare system, experts say the findings highlight the need for integrated care models that address both mental and physical health. 

Researchers from the University of Edinburgh used data from more than 142,000 people in the UK Biobank study to examine how physical illnesses interact to influence the risk of depression – a condition that often goes underdiagnosed in people managing long-term physical diseases.  

Participants were aged 37-73 years and had at least one chronic physical condition but no history of depression.  

Scientists used statistical clustering techniques to group individuals by their physical illness profiles and tracked how these clusters related to later diagnoses of depression.  

One group, which included people experiencing the highest rates of physical illness also showed the highest risk of developing depression. This group had no single dominant illness, but rather a complex mix of issues.  

People with both heart disease and diabetes were also found to be at high risk, as were those with chronic lung conditions like asthma or COPD – chronic obstructive pulmonary disease. Liver and bowel conditions also showed a noticeable link to depression in both men and women. 

Women with joint and bone problems, such as arthritis, were particularly affected, but this pattern was not as prominent for men.  

In the highest-risk groups, about one in 12 people developed depression over the next 10 years, compared with about one in 25 people without physical conditions.  

While the biological burden of illness may play a role, researchers say social and systemic factors could also help explain why physical multimorbidity leads to worse mental health outcomes.  

Lauren DeLong, lead author and PhD student at the University of Edinburgh’s School of Informatics, said: “We saw clear associations between physical health conditions and the development of depression, but this study is only the beginning. We hope our findings inspire other researchers to investigate and untangle the links between physical and mental health conditions.” 

Bruce Guthrie, Professor of General Practice at the University of Edinburgh’s Advanced Care Research Centre, said: “Healthcare often treats physical and mental health as completely different things, but this study shows that we need to get better at anticipating and managing depression in people with physical illness.” 

Professor Mike Lewis, NIHR's Scientific Director of Innovation, said: "Harnessing the power of data to understand the impact of chronic conditions is going to transform the way we treat patients in the future. NIHR's research in this area is helping to paint a full picture of what patients are dealing with, rather than just focusing on one health condition at a time." 

The study is published in the journal Nature Communications Medicine: https://www.nature.com/articles/s43856-025-00825-7 [URL will become active after embargo lifts]. It was funded by the Medical Research Council and the National Institute for Health and Care Research. 

For further information, please contact: Guy Atkinson, Press and PR Office, 07816 392904, guy.atkinson@ed.ac.uk  

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