Changes in the body can be detected up to eight years before inflammatory bowel disease diagnosis, research suggests.
Researchers at the Francis Crick Institute and Aalborg University in Denmark have shown that changes can appear in blood tests up to three years before a diagnosis of ulcerative colitis, and up to eight years before a diagnosis of Crohn’s disease.
The findings suggest the beginnings of inflammatory bowel diseases start a long time before symptoms occur.
In the future this may enable doctors to take preventative action before symptoms begin, or prescribe medication when it will be most effective.
Our research shows that the bowel damage we’re seeing at the point of diagnosis is just the tip of the iceberg— James Lee, Francis Crick Institute
It had previously been thought that most people have symptoms for about a year before diagnosis, but significant bowel damage is often seen, suggesting changes have been taking place for a lot longer.
James Lee, group leader of the Genetic Mechanisms of Disease Laboratory at the Crick, said: “Our research shows that the bowel damage we’re seeing at the point of diagnosis is just the tip of the iceberg.
“So many changes are subtly taking place in the body before the disease takes hold.
“This has huge implications for prevention as it highlights that there’s a window of opportunity for treatment.
“We don’t yet know whether preventative measures like changing diet or stopping smoking would stop someone getting these diseases, but this opens the door to that possibility.
“It also underscores the importance of early diagnosis and treatment, as many of the changes in the gut are likely to have been happening long before people become ill.”
Crohn’s disease and ulcerative colitis are collectively known as inflammatory bowel diseases (IBD).
The conditions are incurable and involve excessive inflammation in the gut, leading to symptoms such as abdominal pain and diarrhoea.
Understanding the exact mechanisms behind their development is essential to ultimately prevent the diseases from occurring— Tine Jess, Aalborg University
Even though early diagnosis and treatment are key to improving outcomes, data suggests nearly a quarter of the 25,000 people diagnosed each year in the UK wait more than a year.
In the study researchers used electronic health records from people in Denmark, comparing 20,000 people with an IBD diagnosis with 4.6 million people without the condition.
The researchers looked at 10 years of test results before diagnosis and found changes in a series of minerals and cells in the blood.
They also looked at markers of inflammation, such as faecal calprotectin, a molecule released into the gut during inflammation and currently used to determine which people with bowel symptoms need further investigations.
According to the findings, published in Cell Reports Medicine, these changes were observed up to eight years before diagnosis in Crohn’s disease and three years in ulcerative colitis.
However, most of the changes would have appeared within a normal range for standard blood tests, and were only detected because of the size of the study.
The next steps are to investigate if treatment or prevention has an impact before people get symptoms, and whether the findings from this research could be developed further to predict who will develop IBD in the future.
Tine Jess, director at the Centre for Molecular Prediction of Inflammatory Bowel Disease, PREDICT, at Aalborg University, said: “Our findings are novel and go hand-in-hand with emerging evidence that chronic inflammatory bowel diseases likely have their onset years prior to diagnosis.
Anything that could potentially speed up the process of getting an accurate diagnosis is a hugely positive step in the right direction— Sarah Sleet, Crohn’s and Colitis UK
“These incurable diseases affect young individuals and are twice as common as type 1 diabetes.
“Understanding the exact mechanisms behind their development is essential to ultimately prevent the diseases from occurring.”
Sarah Sleet, chief executive of Crohn’s and Colitis UK, said: “There are over 500,000 people in the UK with Crohn’s and colitis.
“We know that earlier diagnosis leads to better outcomes for everyone, but waiting lists for diagnostic tests can be long.
“Not only that, many people put off going to the GP to get their symptoms checked out – either because they don’t realise how serious they could be, or through fear or embarrassment.
“Anything that could potentially speed up the process of getting an accurate diagnosis is a hugely positive step in the right direction.”
