IBD Symptoms May Show Up Years Before Clinical Diagnosis, Study Shows

Symptoms of inflammatory bowel disease (IBD) may start years before typical diagnostic tests can identify the disease.

New research published in the journal PLOS Medicine shows that IBD may have a “substantial symptomatic period” before clinical diagnosis; symptoms may show up 10 years or more before an endoscopy and biopsy can identify the disease.

Further, people who present with IBD-specific symptoms (abdominal pain, diarrhea, or rectal bleeding) but receive a normal endoscopy still have an elevated risk of IBD over the next 30 years.

“Clinicians should be aware that patients with GI symptoms that require an endoscopy are at an increased risk for IBD in the future, even if their endoscopies have been normal,” lead study author Jiangwei Sun, PhD, a postdoctoral researcher in the Department of Medical Epidemiology and Biostatistics at the Karolinska Institutet in Sweden, told Health.

IBD—an umbrella term used to describe Crohn’s disease and ulcerative colitis—affects about 3 million Americans, most of whom are diagnosed before the age of 35. The disease causes chronic inflammation in the gastrointestinal (GI) tract, but early warning signs are sometimes indistinguishable from other conditions, making IBD difficult to diagnose early.

Normal Biopsy May Not Protect Against Future Diagnosis

For the study, published in February, Sun and his team evaluated GI biopsy reports from Sweden’s national health database. All had been taken between 1965 to 2016. The researchers looked at people with a GI biopsy of normal mucosa—or a GI tract lining free from clinically-detected disease—specifically.

In total, the team identified nearly 460,000 people who had a normal lower or upper GI biopsy (200,495 lower GI biopsy and 257,192 upper GI biopsy) and nearly half a million of their siblings who had not had a GI biopsy. They also included 2 million people from the Swedish Total Population Register who also had not undergone a GI biopsy during that time frame.

The median follow-up time was 10 years, though for some it was as much as 30 years after they had undergone a GI biopsy. They found that 2.4% of people who had a normal lower GI biopsy later developed IBD, compared to 0.4% of those who had not. People who had a normal upper GI biopsy also had a higher risk of later developing Crohn’s disease or ulcerative colitis. 

But Jeffrey Berinstein, MD, a gastroenterologist and clinical instructor at Michigan Medicine, who was not involved in the study, emphasized that although the risk was increased, the relative number of people affected was still low. 

“Even though the relative increase in those who got biopsies compared to those who did not, the absolute number is less than 10% who undergo endoscopy. It shouldn’t deter people from getting a biopsy,” he said. 

The difference between 2.4% and 0.4% worked out to be one additional IBD diagnosis for every 37 people within 30 years of a normal biopsy. 

A Disease That's Difficult to Detect and Diagnose

The most common symptoms of IBD include abdominal pain, diarrhea, changes in bowel habits, or rectal bleeding, according to Sun. But some of those symptoms may also occur in other more common conditions, such as irritable bowel syndrome (IBS) or hemorrhoids, which can make IBD diagnoses difficult.

It’s often not until the disease progresses and causes obvious blood in the stool, anemia, or weight loss, that it becomes clear a patient likely has IBD and needs proper diagnostic tests.

Physicians often call IBD insidious, since symptoms progress slowly and patients often adapt to the symptoms over time, “until they have so much bowel damage that the diagnosis is then obvious,” said Stefan Holubar, MD, a colorectal surgeon, IBD Surgery section chief and director of research in the Department of Colorectal Surgery at Cleveland Clinic, who was not involved in the new study. 

“Those who are at higher risk for IBD and have mild symptoms should ... be established with an IBD specialist so the doctor can see the patient over time, with the goal being of making the diagnosis earlier and starting treatment earlier to prevent inflammation-driven bowel damage,” Dr. Holubar said.

According to Berinstein, not every patient will need a follow-up endoscopy, but physicians should have a low threshold for repeating the procedures if a patient’s symptoms get worse or they don’t respond to non-IBD therapies.

“We have to follow these patients a little more closely and we have to be aware that having symptoms and a negative biopsy doesn’t necessarily rule it out and not be afraid to relook if symptoms don’t improve with non-IBD therapy,” Dr. Berinstein said.

Although IBD is a lifelong disease that requires near-constant maintenance and regular check-ins, it is largely a manageable disease. Advances in medicine as well as experts’ understanding of IBD has made today the “Golden Age” for IBD treatments, Dr. Holubar said—and new and more targeted therapies emerge every year.

“We now have many options in our medicine bags for IBD,” Dr. Holubar said, “to control inflammation and give people as normal a life as possible.”