Facts about Inflammatory Bowel Diseases


Inflammatory bowel diseases (IBD), which include Crohn’s disease and ulcerative colitis, affect as many as 1.6 million Americans, most of whom are diagnosed before age 30. These chronic, life-long conditions can betreated but not cured. IBD can significantly affect patients’ quality of life and may have a high financial burden. By generating greater awareness of Crohn’s disease and ulcerative colitis, the Crohn’s & Colitis Foundation believes that more progress can be made toward finding a cure and reducing the significant impact of these diseases on individuals and the US healthcare system.

The Foundation is pleased to provide this Fact Book, which compiles important statistics and information and offers a brief overview of IBD. This Fact Book will be of use to patients and their families, as well as physicians and others with an interest in broadening their knowledge about IBD.

The Foundation: Dedicated to Finding a Cure

Crohn’s & Colitis Foundation is the largest voluntary non-profit health organization dedicated to finding a cure for IBD. Crohn’s & Colitis Foundation has played a role in almost every major research breakthrough since its founding in 1967. Its mission is to cure Crohn’s disease and ulcerative colitis, and to improve the quality of life of children and adults affected by these diseases. Crohn’s & Colitis Foundation works to fulfill our mission by funding research, providing educational resources for patients and their families, medical professionals, and the public, and furnishing supportive services for people with IBD.

What Are Inflammatory Bowel Diseases?

Inflammatory bowel diseases are a group of inflammatory conditions of the intestines. Crohn’s disease and ulcerative colitis are two inflammatory bowel diseases that cause chronic inflammation in the gastrointestinal (GI) tract. The GI tract is responsible for digestion of food, absorption of nutrients, and elimination of waste. Inflammation impairs the ability of affected GI organs to function properly, leading to symptoms such as persistent diarrhea, abdominal pain, cramping, rectal bleeding, and fatigue. With both Crohn’s disease and ulcerative colitis, patients go through periods of being symptom-free (remission) alternating with periods of having active disease symptoms (flare). While ongoing inflammation in the GI tract occurs in both Crohn’s disease and ulcerative colitis, there are important differences between the two diseases.

Crohn’s disease

Crohn’s disease can affect any part of the GI tract, from the mouth to the anus. It most commonly affects the end of the small intestine (the ileum) where it joins the beginning of the colon. Crohn’s disease may appear in “patches,” affecting some areas of the GI tract while leaving other sections completely untouched. In Crohn’s disease, the inflammation may extend through the entire thickness of the bowel wall of the affected area.

Ulcerative colitis

Ulcerative colitis is limited to the large intestine (colon) and the rectum. The inflammation occurs only in the innermost layer of the lining of the intestine. It usually begins in the rectum and lower colon, but may also spread continuously to involve the entire colon.


While the exact cause of IBD is not entirely understood, it is known to involve an interaction between genes, the immune system, and environmental factors. The GI tract normally contains harmless bacteria, many of which aid in digestion. The immune system usually attacks and kills foreign invaders, such as bacteria, viruses, fungi, and other microorganisms. Under normal circumstances, the harmless bacteria in the intestines are protected from such an attack. In people with IBD, these bacteria are mistaken for harmful invaders and the immune system mounts a response. Cells travel out of the blood to the intestines and produce inflammation (a normal immune system response). However, the inflammation does not subside, leading to chronic inflammation, ulceration, and thickening of the intestinal wall. This abnormal immune system reaction occurs in people who have inherited genes that make them susceptible to IBD. Unidentified environmental factors serve as the “trigger” that initiates the harmful immune response in the intestines.

Historical Perspective and Research Advances

Ulcerative colitis was first described in 1875 by two English physicians, Wilks and Moxon, who distinguished it from diarrheal diseases caused by infectious agents. Reports of a disease with similar symptoms to ulcerative colitis date back to before the Civil War and even many years before that, although it was not named as a distinct disease until 1875. Crohn’s disease was first described in 1932 by three doctors—Burrill Crohn, Leon Ginzberg, and Gordon D. Oppenheimer. At the time, any disease in the small intestine was thought to be intestinal tuberculosis. These doctors collected data from 14 patients with symptoms of abdominal cramps, diarrhea, fever, and weight loss, which showed that the symptoms were not the result of tuberculosis or any other known disease. They described a new disease entity, which was first called regional ileitis, and later, Crohn’s disease. Reports of diseases with symptoms similar to Crohn’s disease date back to the early 1900’s.

In the years since inflammatory bowel diseases were identified, research has been underway to better understand these diseases, to uncover the causes, and to develop effective treatments. Major scientific advances, specifically in the fields of genetics, immunology, and microbiology, have led to greater understanding of the underlying mechanisms involved in IBD, resulting in the development of increasingly effective treatments.

What Are the Signs and Symptoms of IBD?

As the lining of the intestine becomes inflamed and ulcerated, it loses its ability to adequately process food and waste or absorb water, resulting in loose stools (diarrhea). Most people with Crohn’s disease or ulcerative colitis experience an urgency to have a bowel movement and have crampy abdominal pain. Inflammation can cause small sores (ulcers) to form in the colon and rectum. These can join together and become large ulcers that bleed, resulting in bloody stools. Blood loss can eventually lead to anemia if unchecked. The symptoms of IBD vary from person to person, and may change over time. Symptoms can range from mild to severe. People with Crohn’s disease and ulcerative colitis often go through periods when the disease is quiet with few or no symptoms present (remission), alternating with times when the disease is active and causing symptoms (flares).

Symptom Recurrence

Crohn’s disease:

Because Crohn’s disease can occur in various areas of the GI tract, disease activity and severity can vary widely over time. Most patients have active disease at the time Crohn’s disease is diagnosed.

With medical and/or surgical treatment:

  • About 50% of patients will be in remission or have mild disease over the next five years
  • 45% of those in remission will remain relapse-free over the next year
  • 35% will have one or two relapses
  • 11% will have chronically active disease

For a Crohn’s disease patient in remission, relapse rates at one, two, five, and ten years are estimated at 20%, 40%, 67%, and 76%, respectively. (2)

Ulcerative colitis:

In a given year:

  • 48% of people with ulcerative colitis are in remission
  • 30% have mild disease activity
  • 20% have moderate disease activity
  • 1% to 2% have severe disease (1)

Seventy percent of patients who have active disease in a given year will have another episode of active disease in the following year. Only 30% of those in remission in a given year will have active disease in the following year. The longer a person with ulcerative colitis remains in remission, the less likely he or she is to experience a flare-up of the disease in the following year.

Disease Progression Over Time

Once IBD has been diagnosed, the symptoms can almost always be effectively managed. However, Crohn’s disease and ulcerative colitis are chronic illnesses, and changes are likely to occur over time. Symptoms may recur at times and complications may develop.

IBD Complications

In addition to the signs and symptoms of IBD described on the preceding pages, some people develop complications that may require urgent medical care.

Complications of ulcerative colitis include:

  •  Heavy, persistent diarrhea, rectal bleeding, and pain
  • Perforated bowel—chronic inflammation of the intestine may weaken the intestinal wall to such an extent that a hole develops
  • Toxic megacolon—severe inflammation that leads to rapid enlargement of the colon

Complications of Crohn’s disease include:

  • Fistula—inflammation can cause ulcers to form on the inside wall of the intestines or other organs. These ulcers can extend through the entire thickness of the bowel wall and form a tunnel (fistula) to another part of the intestine, between the intestine and another organ, or to the skin surface
  • Stricture—a narrowing of a section of intestine caused by scarring, which can lead to an intestinal blockage
  • Abscess—a collection of pus, which can develop in the abdomen, pelvis, or around the anal area
  • Perforated bowel—chronic inflammation of the intestine may weaken the wall to such an extent that a hole develops
  • Malabsorption and Malnutrition
  • Nutritional deficiencies—can develop due to an inability to absorb nutrients such as proteins, vitamins, and fats

Complications Outside the GI Tract

Not all complications of IBD are confined to the GI tract. For reasons that are not entirely understood, some people develop symptoms that are related to the disease but affect other parts of the body. The most common of these complications affect the skin and bones.3 These extraintestinal complications may be evident in the:

  • eyes (redness, pain, and itchiness)
  • mouth (sores)
  •  joints (swelling and pain)
  • skin (tender bumps, painful ulcerations, and other sores/rashes)
  • bones (osteoporosis)
  •  kidney (stones)
  • liver (primary sclerosing cholangitis, hepatitis, and cirrhosis)—occurs rarely


Death due specifically to Crohn’s disease or its complications is uncommon. However, people with Crohn’s disease have a statistically slightly higher overall mortality rate than would otherwise be expected compared with the general healthy population. The increase in deaths is largely due to conditions such as cancer (particularly lung cancer), chronic obstructive pulmonary disease, gastrointestinal diseases, (both including and excluding Crohn’s disease), and diseases of the genital and urinary tracts. (4)

Death due to ulcerative colitis or its complications is also uncommon. Most people with ulcerative colitis do not have a higher risk of dying from any particular disease than the general population. However, those with extensive inflammation in the colon are at higher risk than the general population for dying from gastrointestinal and lung diseases (although not lung cancer). (5)

Who Is at Risk?

IBD is a complex disease that results from the interaction of an individual’s genes with environmental factors and the immune system.


Scientific evidence clearly points to the role of heredity in IBD. Studies have shown that 5% to 20% of affected individuals have a first-degree relative (parent, child, or sibling) with one of the diseases.6 Children of parents with IBD are at greater risk than the general population for developing IBD. (7) The risk is greater with Crohn’s disease than with ulcerative colitis. The risk is also substantially higher when both parents have IBD. One study found that 36% of people with both parents affected developed IBD. (8)

Further evidence for the importance of genetics in IBD comes from studies of identical twins. If one twin has ulcerative colitis, his or her identical twin has a one in five lifetime risk of developing IBD. If one twin has Crohn’s disease, his or her identical twin has a one in three lifetime risk of developing IBD.

While genetics is clearly a factor, the association is not simple. It is likely that more than one gene is at work, and just having the genes associated with IBD doesn’t absolutely predict the disease will occur. Instead, these are susceptibility genes, which increase the chances for getting the disease. It is clear that other factors, including environmental factors, must also come into play.

Numerous genes and genetic mutations connected to IBD have been identified. The first one discovered was a mutation in the NOD2/CARD15 gene, which was found to be associated with developing Crohn’s disease.9 Up to 20% of IBD patients in North America and Europe may have a mutation in the NOD2/CARD15 gene. While genetic testing to identify whether a person has one or more susceptibility genes is possible, it is not currently a part of the diagnostic process. This is because many people who carry these genes will never develop IBD. So, at this time genetic testing can identify a potential risk for IBD in an individual, but cannot predict whether or not they will develop it.

Environmental Triggers

The environmental factors that trigger IBD are not known, but several potential risk factors have been studied. More studies are needed to fully understand the risk factors for IBD.

  • Smoking—Active smokers are more than twice as likely as nonsmokers to develop Crohn’s disease. (12) Surprisingly, the risk of developing ulcerative colitis is decreased in current smokers compared with people who have never smoked. The numerous potential harmful health effects of smoking (e.g., cancer, heart disease) largely overcome any benefits of smoking for people with ulcerative colitis.
  • Antibiotics—May increase the risk for IBD.
  • Nonsteroidal anti-inflammatory drugs (aspirin, ibuprofen, naproxen)— May increase the risk for getting IBD and may worsen the condition.
  • Appendicitis in children—Children who undergo an appendectomy (removal of the appendix) are less likely to develop ulcerative colitis later in life. However, appendectomy in childhood may increase the risk for Crohn’s disease.
  • Diet—IBD is not triggered by eating any one particular food. But for some people, certain foods can aggravate symptoms. The role of diet in Crohn’s disease and ulcerative colitis is an important subject, and more research is needed to better understand how diet may impact these diseases.
  • Age–Although Crohn’s disease and ulcerative colitis can occur at any age, people are more frequently diagnosed between the ages of 15 and 30. A population-based study conducted from 1940 to 2000 in Olmsted County, Minnesota, examined the incidence of IBD. The total number of new cases of ulcerative colitis diagnosed each year (incidence) was just over two per 100,000 people ages 0 to 19. The incidence climbed to just under 14 per 100,000 people ages 20 to 29. The incidence started to decline from then on, with a slight increase in the 50 to 59 age group. The study showed similar trends for Crohn’s disease.
  • Gender–In general, IBD affects men and women equally, although the study from Olmsted County, Minnesota, found a higher incidence of ulcerative colitis in men. In addition, men are more likely than women to be diagnosed with ulcerative colitis in their 50’s and 60’s.
  • Geographic distribution–IBD is found mainly in developed countries, more commonly in urban areas, and more often in northern climates. However some of these disease patterns are gradually shifting. The highest Crohn’s disease incidence is reported in Canada while highest ulcerative colitis rates are reported for Denmark, Iceland, and the United States. Two major epidemiological studies were conducted in the United States, one in California and the other in Minnesota.

Racial and Ethnic Impacts

IBD can affect anyone: however, Caucasians are more likely than other ethnic groups to have IBD. The diseases are especially prevalent in Jews of European descent (Ashkenazi Jews). African Americans and Hispanics in the United States are increasingly affected. Nationwide epidemiologic data (such as incidence and prevalence) about minority populations with IBD are not available. One small study of IBD patients in California looked at interracial variations in disease characteristics. It included Caucasian, African American, Hispanic, and Asian subjects.15  For example, Asians were diagnosed with IBD at older ages than Caucasians and African Americans, and Hispanics were diagnosed at older ages than Caucasians. A higher proportion of Caucasians had a family history of IBD than African Americans or Asians.

Other research shows that people of various ethnic groups who have immigrated to the United States from countries with low incidences of ulcerative colitis have higher rates of developing the disease once living in this country.16 This suggests that race and ethnicity alone are probably not the sole determining factors, and that as yet unexplained environmental influences are at work.

Racial Variations

Data from the Multicenter African American IBD Study and the National Institute of Diabetes and Digestive and Kidney Diseases IBD Genetics Consortium suggest that there are differences in symptoms and location of disease among racial and ethnic groups. African Americans with Crohn’s disease are more likely than Caucasians to have disease in the colon or upper GI tract (esophagus, stomach, and first section of the small intestine).17 They are also less likely to have disease in the last section of the small intestine (terminal ileum). African Americans are also more likely to have certain extraintestinal complications, such as uveitis (swelling/irritation of the eye). Hispanics have a higher prevalence of a skin disorder called erythema nodosum (tender, red nodules beneath the skin).

Special Populations

IBD can affect men and women of all ages. For certain populations of IBD patients—such as children, women of childbearing age, and older adults—there are special considerations regarding these diseases.


Most people with IBD are diagnosed after age 15. IBD can be diagnosed at a younger age, although it is rare in children younger than eight years of age. An estimated 50,000 children (under age 20) in the United States have IBD, representing five percent of all IBD patients.18 However, the number of children with IBD appears to be increasing in recent years. In children, Crohn’s disease occurs twice as frequently as ulcerative colitis. Slightly more boys than girls develop IBD (especially Crohn’s disease) in childhood. (19)

When IBD is diagnosed in childhood it may be more extensive and follow a more severe course than when it is diagnosed in adulthood.20 Some children with IBD experience delayed puberty and some fail to grow at a normal rate (growth failure).21 In approximately one-third of children with Crohn’s disease and one-tenth of children with ulcerative colitis, their final adult height is less than expected because of their IBD.


For women of childbearing age with IBD, there are considerations related to fertility and pregnancy. During times when the disease is in remission, women with Crohn’s disease or ulcerative colitis have normal fertility rates. When the disease is active, conceiving a child may be more difficult and fertility may be affected, at least temporarily. Some people with ulcerative colitis may need to have surgery to remove the colon and rectum. Studies show that in women who have ileoanal J-pouch surgery, fertility rates are reduced to about one-third of normal. This is thought to be due to scarring and/or blockage of the fallopian tubes from inflammation and/or postoperative surgical scarring.

Ideally, women with IBD should be in remission for six months before becoming pregnant. For women in remission or with mild disease at the time of conception, the birth will almost always be normal. The risk for complications, such as miscarriage, stillbirth, and developmental defects, is increased when the disease is active at the time of conception and during pregnancy. Most women with Crohn’s disease can deliver vaginally, but cesarean delivery may be preferred for patients with anorectal and perirectal abscesses and fistulas to reduce the likelihood of more fistulas developing or extending into an episiotomy scar.

Older Adults

An estimated 8% to 16% of cases of IBD are diagnosed in people 60 years of age and older. For the most part, the symptoms and features of the diseases when diagnosed in the elderly are the same as when diagnosed at a younger age. However, symptoms of diarrhea and bleeding are more likely to be present at diagnosis in older adults compared with younger IBD patients. In addition, the diagnosis of IBD is more likely to be missed or delayed in older adults compared with younger adults. (22)

IBD patients older than 60 years experience twice as many drug-related adverse events, but the risk of steroid-associated complications is similar to those younger than age 65.23 Other goals of medical treatment are to heal the lining of the GI tract, avoid hospitalization, and, if possible, avoid surgery. Eventually, some people with Crohn’s disease or ulcerative colitis will require surgery. There is no standard regimen for managing all people with IBD. The approach to treatment must be tailored to the individual. Factors that determine the approach to treatment include:

  • Disease severity
  • Anatomic location of disease
  • Previous response to medication
  • Side effects of medication
  • Comorbidities (other diseases or medical conditions that the person has)


Treatment with medication is the first therapeutic option.24 The main goals of medical treatment are to achieve remission (the absence of symptoms) and, once that is accomplished, to maintain remission (prevent flare-ups of symptoms).

Medical Treatment

There are five main categories of medications used to treat IBD:

Aminosalicylates: These are anti-inflammatory compounds that contain 5-aminosalicylic acid (5-ASA). Examples are sulfasalazine, balsalazide, mesalamine, and olsalazine. These drugs (given orally or rectally) act to decrease inflammation at the wall of the intestine. They are effective in treating mild-to-moderate episodes of Crohn’s disease and ulcerative colitis, as well as preventing relapses and maintaining remission.

Up to 75% of patients with ulcerative colitis are helped with aminosalicylates. They are somewhat less effective for Crohn’s disease.

Corticosteroids: These medications, which include prednisone, prednisolone, and budesonide, affect the body’s ability to begin and maintain an inflammatory process. They keep the immune system in check. They are effective for short-term control of flare-ups. They are not recommended for long-term or maintenance use because of their side effects, which can include infection, bone loss, weight gain, cataracts, skin fragility, sleep disturbance, and mood swings.

Immunomodulators: This class of medications modifies the activity of the immune system so that it cannot cause ongoing inflammation. Examples include azathioprine, 6-mercaptopurine (6-MP), and methotrexate. These drugs are generally used to maintain remission in people who have not responded to other medications. Forty-two percent of patients with Crohn’s disease will achieve remission on azathioprine.

Antibiotics: The antibiotics ciprofloxacin and metronidazole have modest benefit for people with Crohn’s disease that affects the colon or the area around the anus. They may be used when infections, such as abscesses, occur. There is no substantial scientific evidence to support the use of antibiotics in the treatment of ulcerative colitis.

Biologic therapies: These are the most recently developed treatments for IBD. Three of these agents (adalimumab, certolizumab pegol, and infliximab) target an inflammatory protein called tumor necrosis factor (TNF). These medications are indicated for people with moderate to severe active disease who have not responded well to conventional therapy. The three anti-TNF medications are FDA-approved for the treatment of Crohn’s disease; only infliximab is also approved for ulcerative colitis. Approximately 60% of patients with IBD respond to these biologic therapies; of these, about 35% will be in remission at the end of one year. A fourth biologic agent, natalizumab, is an antibody that inhibits certain types of white blood cells that are involved in the inflammatory process. It is approved only for Crohn’s disease.

Surgical Treatment

Medication may not adequately control symptoms for everyone with IBD, and some people with these conditions develop complications that require surgery.

  •  After 30 years of disease, up to a third of people with ulcerative colitis will require surgery. The standard surgical procedure for ulcerative colitis is removal of the colon and rectum. Patients who undergo this procedure are cured of ulcerative colitis. Most patients who have surgery for ulcerative colitis can have a procedure called an ileo pouch-anal anastomosis (IPAA). In this procedure, after the entire colon and rectum is removed, the small intestine is attached to the anal area, allowing the patient to continue to pass stool through the anus. An IPAA is not the best surgical treatment for all patients with ulcerative colitis. Some patients will need a permanent ileostomy, where the fecal waste empties into an external bag attached to the patient’s abdomen. These patients are also cured of their ulcerative colitis and typically have an excellent quality of life.
  • About 70% of people with Crohn’s disease eventually require surgery. Different types of surgical procedures may be performed for Crohn’s disease, depending on the reason for surgery, severity of illness, and location of the disease in the intestines. Unlike ulcerative colitis, surgery does not cure Crohn’s disease. Approximately 30% of patients who have surgery for Crohn’s disease experience recurrence of their symptoms within three years and up to 60% will have recurrence within ten years.25

Risk of Other Diseases

IBD patients are at a slightly greater risk for some other diseases, including colon cancer, blood clots, and a liver disease called primary sclerosing cholangitis (PSC).

Risk for Cancer

People with Crohn’s disease or ulcerative colitis have a higher risk for colorectal cancer than the general population. Colorectal cancer rarely occurs in the first eight to ten years after initial diagnosis of IBD. The risk increases the longer a person lives with the disease. An analysis of all published studies found that as many as 18% of people with IBD may develop colorectal cancer by the time they have had IBD for 30 years.26 The degree of increased risk is also related to the length of colon involved and the severity of disease. Because of this increased risk, people with IBD are advised to undergo more frequent colonoscopies than the general population (every one to two years after eight years of disease). The use of certain medications for IBD may increase the risk for lymphoma (blood cancer that originates in the lymphatic system). Two studies found a three to four times increased rate of lymphoma in IBD patients taking medications that suppress the immune system, such as immunomodulators or biologic therapies.27,28 Although this may seem alarming, the overall risk is very low; less than one percentof IBD patients taking these medications will ever develop lymphoma.

Risk for Blood Clots

People with IBD have about a three times greater risk than the general population for developing deep vein thrombosis (a blood clot that forms in a vein deep in the body) or pulmonary embolism (a blood clot causing a sudden blockage in a lung artery).29 Hospitalized IBD patients appear o be at even greater risk. Treatment with blood thinners while in the hospital can reduce the risk of blood clots.

Risk for primary sclerosing cholangitis (PSC)

PSC is a form of severe inflammation and scarring that develops in the bile ducts. About half of all PSC patients have IBD. PSC occurs more frequently in people with ulcerative colitis than in those with Crohn’s disease and affects men more than women. Symptoms include jaundice, nausea, weight loss, and itching. About five percent of patients with ulcerative colitis (those with extensive disease) and one percent of patients with Crohn’s disease develop this condition. The cause is not known and  there is no effective medication for PSC. A liver transplant may ultimately be required.

In Crohn’s disease, a recent review of studies30 showed that complications inside the GI tract (such as strictures) occurred in:

  • up to 33% of patients at the time of diagnosis
  • approximately 50% of patients within 20 years of diagnosis

In ulcerative colitis:

  • 50% of patients have mild disease at the time of diagnosis
  • up to 19% of patients have severe disease at the time of diagnosis
  • 90% of patients have at least one relapse of active symptoms within 25 years of diagnosis

Use of the Healthcare System

People with IBD most often receive care in physicians’ offices or other outpatient sites. Hospitalization is required for severe disease, to treat certain complications, and for surgery.

Crohn’s Disease (31)

  • In 2004 there were more than 800,000 physician office visits in the United States specifically for Crohn’s disease.
  • The overall number of physician office visits for Crohn’s disease increased by 74% from 1992 to 2004. In 2004 there were 57,000 hospitalizations specifically for Crohn’s disease.
  • Rates of hospitalization were relatively stable from 1979 to the early 1990s, but then increased modestly.

Ulcerative Colitis

  • In 2004 there were about 500,000 physician office visits in the United States specifically for ulcerative colitis.
  • The overall number of physician office visits for ulcerative colitis increased from 1992 to 2004.
  • In 2004 there were 35,000 hospitalizations specifically for ulcerative colitis.
  • Rates of hospitalization were relatively stable from the 1970s, but increased 67% in the years 1999 to 2004.

Burden of Disease

Impact on Patients

Patients with Crohn’s disease and ulcerative colitis can and do lead full and productive lives. However, when these diseases are active they can have significant impact on the quality of life for patients due to flare-ups and complications. Complications, which are described in the “Signs and Symptoms” section, can occur inside or outside the GI tract.

Psychological Health

Having a chronic illness such as IBD can be emotionally burdensome. Symptoms of IBD can flare up unexpectedly and can be painful, uncomfortable, inconvenient, and embarrassing. IBD patients may experience a wide range of emotions in response to having these conditions. Some IBD patients react to the unpredictable and sometimes severe nature of IBD symptoms with feelings of anger, anxiety, or fear. They may also have elevated stress levels. In addition, stressful situations (even those unrelated to the disease itself) may lead to flare-ups of symptoms. Depression is a serious disorder that can affect some people with IBD. However, depression is treatable with psychological counseling and/or antidepressant drugs. Mental health counseling and support groups can be extremely helpful in dealing with the psychological impact of IBD.

Direct Costs

  • Total annual direct costs for all patients with IBD (both Crohn’s disease and ulcerative colitis) in the United States in the year 2004 (the last year for which data are available) were $1.84 billion. (32)
  • Mean annual direct costs for Crohn’s disease were $8,265 per patient (based on 2003- 2004 US insurance claims data). (33)
  • Mean annual direct costs for ulcerative colitis were $5,066 per patient (based on 2003- 2004 US insurance claims data).

Indirect Costs

  • Total annual indirect costs for all patients with IBD in the United States in the year 2004 were $328 million.
  • Based on a national health survey in 1999, nearly 32% of symptomatic IBD patients reported being out of the workforce in a one-year period, incurring an indirect cost of an estimated $5,228 per patient. (34)

The total annual financial burden (adding direct and indirect costs) of IBD in the United States is an estimated $2.2 billion.

Financial Burden

There are both direct and indirect costs associated with IBD. Direct medical costs include expenses for hospitalizations, physician services, prescription drugs, over-the-counter drugs, skilled nursing care, diagnostic procedures, and other healthcare services. Indirect costs are the value of lost earnings or productivity. Indirect costs also include the value of leisure time lost.

What We Know Now

In the decades since ulcerative colitis and Crohn’s disease were identified, significant scientific progress has been made in understanding these chronic inflammatory diseases. Advances in basic science (particularly immunology, genetics, and microbiology) have added to the knowledge about the causes of the diseases and have provided targets for developing new treatments.

An increasing number of susceptibility genes have been identified. The list of genes that have been found to play a role in Crohn’s disease is rapidly expanding (see Figure 8). In 2007, eight such genes had been identified. By 2010, that number grew to over 70 genes. In addition, the importance of what is called the microbiome has been recognized. The microbiome comprises all the microorganisms (bacteria, viruses, fungi, and other microbes) that reside in or on the human body. An important area of IBD research involves identifying the constellation of bacteria that reside in the intestines and understanding how they communicate and interact within the intestines and with the immune system.

Genes affect three types of traits:

  • Immune regulation
  • Mucosal barrier and cellular stress
  • Policing of bacteria

A greater understanding of the underlying mechanisms of IBD has already led to the development of novel treatments, such as biologic agents used to treat people with moderate to severe Crohn’s disease or ulcerative colitis. Even newer treatments have been developed which are being tested in clinical trials. New technological advances should allow research to move even faster. The Crohn’s & Colitis Foundation is a critical source of funding for the IBD research community. Crohn’s & Colitis Foundation was the first lay organization dedicated to supporting research into the causes of and cures for IBD, as well as improving treatments. Since its founding in 1967, Crohn’s & Colitis Foundation has provided over $150 million in research awards. Crohn’s & Colitis Foundation's research investments have led to some of the major breakthroughs in understanding and treating IBD.

Ongoing funding for research is needed. One day we will will find a cure for these diseases.


1. Langholz E, Munkholm P, Davidsen M, Binder V. Course of ulcerative colitis: analysis of changes in disease activity over years. Gastroenterology. 1994;107:3-11.

2. Lapidus A, Bernell O, Hellers G, Lofberg R. Clinical course of colorectal Crohn’s disease: a 35-year follow-up study of 507 patients. Gastroenterology. 1998;114:1151-1160.

3. Ephgrave K. Extraintestinal manifestations of Crohn’s disease. Surg Clin North Am. 2007;87(3):673-680.

4. Duricova D, Pedersen N, Elkjaer M, et al. Overall and cause-specific mortality in Crohn’s disease: a meta-analysis of population-based studies. Inflamm Bowel Dis. 2010;16:347-53.

5. Jess T, Gamborg M, Munkholm P, Sørensen TIA. Overall and cause-specific mortality in ulcerative colitis: meta-analysis of population-based inception cohort studies. Am J Gastroenterol. 2007;102:609-617.

6. Russell RK, Satsangi J. Does IBD run in families? Inflamm Bowel Dis. 2008;14(S2):S20-S21.

7. Noble CL, Arnott IDR. What is the risk that a child will develop inflammatory bowel disease if one or both parents have IBD? Inflamm Bowel Dis. 2008;14(S2):S22-S23.

8. Bennett RA, Rubin PH, Present DH. Frequency of inflammatory bowel disease in offspring of couples both presenting with inflammatory bowel disease. Gastroenterology. 1991;100:1638-1643.

9. Noomen CG, Hommes DW, Fidder HH. Update on genetics in inflammatory disease. Best Pract Res Clin Gastroenterol. 2009;23(2):233-243.

10. Loftus EV, Jr. Clinical epidemiology of inflammatory bowel disease: incidence, prevalence, and environmental influences. Gastroenterology. 2004;126(6):1504-1517.

11. Bernstein CN. Assessing environmental risk factors affecting the inflammatory bowel diseases: a joint workshop of the Crohn’s & Colitis Foundations of Canada and the USA. Inflamm Bowel Dis. 2008;14(8):1139-1146.

12. Cosnes J. What is the link between the use of tobacco and IBD? Inflamm Bowel Dis. 2008;14 (Suppl 2):S14-S5.

13. Loftus CG, Loftus EV, Jr., Harmsen WS, et al. Update on the incidence and prevalence of Crohn’s disease and ulcerative colitis in Olmsted County, Minnesota, 1940-2000. Inflamm Bowel Dis. 2007;13:254-261.

14. Herrinton LF, Liu L, Lewis JD, Griffin PM, Allison J. Incidence and prevalence of inflammatory bowel disease in a Northern California managed-care organization, 1996-2002. Am J Gastroenterol. 2008;103(8):1998-2006.

15. Sewell JL, Inadomi JM, Yee HF, Jr. Race and inflammatory bowel disease in an urban healthcare system. Dig Dis Sci. 2010;55:3479-3487.

16. Probert CS, Jayanthi V, Pinder D, Wicks AC, Mayberry JF. Epidemiological study of ulcerative proctocolitis in Indian migrants and the indigenous population of Leicestershire. Gut. 1992;33:687-693.

17. Nguyen GC, Torres EA, Regueiro M, et al. Inflammatory bowel disease characteristics among African Americans, Hispanics, and non-Hispanic whites: characterization of a large North American cohort. Am J Gastroenterol. 2006;101(5):1012-1023.

18. Kappelman MD, Rifas-Shiman SL, Kleinman K, et al. The prevalence and geographic distribution of Crohn’s disease and ulcerative colitis in the United States. Clin Gastroenterol Hepatol. 2007;5:1424-1429. 23

19. Kugathasan S, Hoffmann RG. The incidence and prevalence of pediatric inflammatory bowel disease (IBD) in the USA. J Pediatr Gastroenterol Nutr. 2004;30:S48-S49.

20. Van Limbergen J, Russell RK, Drummond, HE, et al. Definition of phenotypic characteristics of childhood-onset inflammatory bowel disease. Gastroenterology. 2008;135:1114-1122.

21. Heuschkel R, Salvestrini C, Beattie RM, Hildebrand H, Walters T, Griffiths A. Guidelines for the management of growth failure in childhood inflammatory bowel disease. Inflamm Bowel Dis. 2008;14(6):839-849.

22. Travis S. Is IBD different in the elderly? Inflamm Bowel Dis. 2008;14:S2.

23. Akerkar GA, Peppercorn MA, Hamel B, et al. Corticosteroid-associated complications in elderly Crohn’s disease patients. Am J Gastroenterol. 1997;92:461-464.

24. Kozuch PL, Hanauer SB. Treatment of inflammatory bowel disease. A review of medical therapy. World J Gastroenterol. 2008;14(3):354-377.

25. Sachar DB. The problem of post-operative recurrence of Crohn’s disease. Med Clin North Am. 1990;74:183-188.

26. Eaden JA, Abrams KR, Mayberry JF. The risk of colorectal cancer in ulcerative colitis: a meta-analysis. Gut. 2001;48(4):526-535.

27. Kandiel A, Fraser AG, Korelitz BI, Brensinger C, Lewis JD. Increased risk of lymphoma among inflammatory bowel disease patients treated with azathioprine and 6-mercaptopurine. Gut. 1005;54(8):1121-1125.

28. Siegel CA, Marden SM, Persing SM, Larson RJ, Sands BE. Risk of lymphoma associated with combination anti-tumor necrosis factor and immunomodulator therapy for the treatment of Crohn’s disease: a meta-analysis. Clin Gastroenterol Hepatol. 2009;7(8):874-881.

29. Nguyen GC, Sam J. Rising prevalence of venous thromboembolism and its impact on mortality among hospitalized inflammatory bowel disease patients. Am J Gastroenterol. 2008;103(9):2272-2280.

30. Peyrin-Biroulet L, Loftus EV Jr, Colombel J-F, Sandborn WJ. The natural history of adult Crohn’s disease in population-based cohorts. Am J Gastroenterol. 2010;105:289-297.

31. Everhart JE. In: Everhart JE, editor. The burden of digestive diseases in the United States. US Department of Health and Human Services, Public Health Service, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases. Washington, DC: US Government Printing Office, 2008; NIH Publication No. 09-6443. pp. 97-106.

32. Ruhl CE, Sayer B, Byrd-Holt DD, Brown DM. In: Everhart JE, editor. The burden of digestive diseases in the United States. US Department of Health and Human Services, Public Health Service, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases. Washington, DC: US Government Printing Office, 2008; NIH Publication No. 09-6443. pp. 137-147.

33. Kappelman MD, Rifas-Shiman SL, Porter CQ, et al. Direct health care costs of Crohn’s disease and ulcerative colitis in US children and adults. Gastroenterology. 2008;135(6):1907-1913.

34. Longobardi T, Jacobs P, Bernstein CN. Work losses related to inflammatory bowel disease in the United States: results from the National Health Interview Survey. Am J Gastroenterol. 2003;98(5):1064-1072.

For further information, call Crohn's & Colitis Foundation's IBD Help Center: 888.MY.GUT.PAIN (888.694.8872).

The Crohn's & Colitis Foundation provides information for educational purposes only. We encourage you to review this educational material with your health care professional. The Foundation does not provide medical or other health care opinions or services. The inclusion of another organization's resources or referral to another organization does not represent an endorsement of a particular individual, group, company or product.

About this resource

Published: May 1, 2011

Downloads available

IBD Factbook (.pdf)
File: 2.32 MB

733 Third Avenue, Suite 510, New York, NY 10017    |    800-932-2423    |    info@crohnscolitisfoundation.org
Powered by Blackbaud
nonprofit software