Inflammatory bowel disease has become more common among American youth

The number of young Americans with inflammatory bowel disease has been rising for years, leaving the U.S. with one of the highest prevalence rates in the world, a new study finds.

More than 100,000 Americans under 20 have IBD — an inflammatory disease that includes Crohn's disease and ulcerative colitis — according to the study, published last month in the journal Gastroenterology. White youth and those in the Northeast had the highest rates of IBD, researchers said. 

MORE: Creative ways to stay active, and burn calories, during the holidays

The study analyzed data from two commercial insurance claims datasets and Medicaid data from five states, including Pennsylvania, to estimate the prevalence of pediatric IBD across the country.

Chron's disease is more common than ulcerative colitis in the pediatric population, researchers found, but ulcerative colitis diagnoses have grown at a faster rate. They increased by 29% since 2009, while Chron's disease diagnoses jumped by 22%.

"Our findings reveal that pediatric IBD affects a significant number of American youth, with prevalence rates among the highest reported worldwide," lead investigator Dr. Michael D. Kappelman, a professor of pediatrics and epidemiology at the University of North Carolina at Chapel Hill, said in a release. "This study provides crucial data to inform healthcare policy, resource allocation, and future research priorities in pediatric IBD."

More research is needed to understand the reasons behind the demographic and geographic variations in pediatric IBD prevalence rates, researchers said. The study was funded by the Centers for Disease Control and Prevention and led by researchers from UNC, the Crohn's & Colitis Foundation and the University of Pennsylvania. 

Pediatric IBD: Causes, symptoms and treatments

IBD affects approximately 1.6 million Americans and is usually diagnosed before age 35, making it one of the most significant chronic diseases affecting children and adolescents, according to the Children's Hospital of Philadelphia.

Issues within the immune system cause the body's antibodies and immune cells to mistake its own healthy cells as invaders and attack them, resulting in inflammation. Crohn's disease can affect any part of the gastrointestinal tract, from the mouth to the anus, and may appear in patches that affect one area of the GI tract and not the next, according to CHOP. Ulcerative colitis involves continuous segments of inflammation in the large intestine and the rectum. Both types of IBD can cause alternating periods of no symptoms, or remission, and periods of inflammatory symptoms, or flares.

Symptoms of IBD vary in children, but they include abdominal pain, diarrhea, blood in the stool, urgent need to move bowels and weight loss. Other symptoms may include skin rashes, joint pain, fatigue or fevers.

The exact cause of IBD is unknown, but research suggests it is caused by an interaction between genes, environmental factors and the immune system. 

To diagnosis children with IBD, a variety of tests and physical examinations are considered, as is the child's health history.  

Treatments aim to relieve symptoms, prevent flares and heal the intestine. They may include medications, nutritional changes or surgery.