Inflammatory Bowel Disease Facts and Statistics: What You Need to Know

Inflammatory bowel disease (IBD) is an umbrella term that’s used for Crohn’s disease, ulcerative colitis, and indeterminate colitis. These conditions affect the digestive tract and other body systems. They are considered common.

A study from 2016 estimates that 1.2 million adults and 57,000 children live with a form of IBD in the United States. The number of people affected by IBD increased between 2007 and 2016, especially in the number of children being diagnosed.

This article will highlight facts and statistics about IBD and how these conditions affect people living in the United States.

Overview

IBD's cause is unknown, but it’s thought to be a result of several factors, including genetics, environment, and the gut microbiome (the germs and microbes that live in the digestive tract).

These diseases cause inflammation in the digestive tract, which can lead to symptoms such as diarrhea, abdominal pain, and bloody stools. Complications can also occur outside the digestive tract, such as arthritis, skin conditions, and eye problems.

How Common is IBD?

In the United States, IBD is thought to affect 1 in 209 adults and 1 in 1299 children. Since 2007, cases of adults with IBD have increased by 123%. In children, the increase was even greater, at 133%.

IBD by Ethnicity

In the past, IBD has largely been considered a disease affecting White people, especially those of Ashkenazi Jewish descent. While it is more common in White people, it is a myth that IBD doesn't, or can't, affect people of other ethnicities.

Even so, data is still lacking on how many people in the United States from various ethnic backgrounds live with an IBD. Not enough studies identify IBD among different groups of people, especially those with smaller populations in the United States.

One study that included people in the United States military showed the prevalence of IBD in other populations, including American Indians. In this study, "Caucasian" was the term used to refer to White people.

The rates of IBD per 100,000 people in this study were:

• Caucasian: 324
  
• Black: 239
  
• Asian: 162
  
• Hispanic: 147
  
• American Indian: 224
  
• Other: 258

The authors report that while the rates of IBD tend to be greater in White people overall, the rates in other racial and ethnic groups "is significantly higher than what is historically believed."

IBD by Age and Gender

Most studies show that all sexes (both children and adults) are diagnosed with IBD in equal numbers. One study showed that in children, males tend to get diagnosed with IBD more often than females. This study also showed that in adults, IBD was diagnosed more in females than in males.

Most people are diagnosed with IBD between the ages of 15 and 35. There's a second, smaller spike in diagnosis in people over 60. For Crohn's disease, one study showed the median age at diagnosis was 29.5. For ulcerative colitis, the median age was 34.9.

With each decade of life, the prevalence of IBD increases. This is because IBD is not commonly fatal, so people tend to live a normal lifespan with it. It's more common for people over 50 to have IBD.

It’s estimated that per 100,000 people, the age distribution of people with IBD is: 

•  0 to 10 years: 25 
• 11 to 19 years: 121 
• 20s: 199 
• 30s: 361 
• 40s: 435 
• 50s: 493 
• 60s: 591 
• 70s: 690 
• 80+: 531

Causes of IBD and Risk Factors

IBD is an idiopathic disease. That is to say, we don’t know what causes it. However, the working theory is that several factors contribute to the development of IBD, including genetics, a disruption in the gut microbiome, and one or more environmental triggers.

It’s not clear exactly how these things may interact to cause IBD, and there may be several ways people can develop IBD.

IBD does tend to run in families. The biggest risk factor appears to be having a close relative with the disease. A child's risk of developing IBD when one parent has the disease is about 3% or less. However, when both parents have a form of IBD, the risk is about 30%.

What Are the Mortality Rates for IBD?

It’s not common for people to die of IBD-related complications. However, people with IBD are at risk of conditions that can be life-threatening. The life expectancy of people with IBD has increased in recent decades. However, one study shows that life expectancy was still a few years lower in people with IBD compared to those without IBD.

Screening and Early Detection of IBD

IBD tends to be difficult and takes a long time to diagnose—from months to even years in some cases. There are various reasons for this, including how the disease differs from person to person and the misconception that IBD doesn’t affect young people or people from historically marginalized groups.

Similarly, older adults may not be diagnosed with IBD promptly. The signs and symptoms are similar to those in younger people, but the diagnosis may take longer.

There are no routine screening tests for IBD. People may have a colonoscopy (examination of the colon with a flexible tube with a camera inserted through the rectum) or other tests or lab work to help make the diagnosis based on symptoms.

Summary

The IBDs are common conditions in the developed world and are becoming increasingly prevalent in the developing world. Outcomes and life expectancy are improving with the improvements in diagnosis and treatments. But the disease is also becoming more commonplace in children.