People with depression are more likely to develop Crohn's disease

A new study, published in Gut, has found depression is more common among people with Crohn's disease or ulcerative colitis in the years before they are diagnosed with these bowel conditions.

Researchers from St George's, University of London, Imperial College London, University College London and King's College London studied the records of fifteen thousand people with ulcerative colitis and Crohn's disease, collectively known as inflammatory bowel diseases or IBD.

They found patients were more likely to be diagnosed with depression up to 9 years before the diagnosis of their IBD compared with people who did not go on to be diagnosed with IBD.

IBD can result in abdominal pain, diarrhoea or rectal bleeding and many people live with these gastrointestinal symptoms for years before being diagnosed. This study examined the link between depression and the chance of later developing IBD.

People who reported GI symptoms before developing depression were 40% more likely to develop IBD compared with people without depression. However, individuals with depression but no prior gastrointestinal symptoms were no more likely to be diagnosed with IBD than individuals without depression.

The study suggests that, on its own, depression is not a risk factor for developing IBD. However, people with depression and previous gastrointestinal symptoms may be more likely to develop either Crohn's disease or ulcerative colitis.

Research Fellow and first author on the paper from St George's, University of London, Dr Jonathan Blackwell, said: "The relationship between depression and IBD is unclear, but it is likely some individuals develop depression as a consequence of gastrointestinal symptoms they experience before being diagnosed with IBD. If you are experiencing depression with abdominal pain, diarrhoea or rectal bleeding, see your doctor and get tested because there may be a treatable cause."

It is possible people become depressed while living with undiagnosed gut symptoms of Crohn's disease or ulcerative colitis. Now, more than ever, during the COVID-19 pandemic it is vital to put strategies in place to ensure timely diagnosis of these bowel conditions to protect people's physical and mental health."

Richard Pollok, Study Senior Author and Professor of Gastroenterology and Gastrointestinal Infection, St George's, University of London