Informatics student leads a study that links higher risk of depression to combinations of chronic illnesses

Researchers discovered 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 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, the chance of developing depression was up to 2.7 times greater than in 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.