Cases of diverticulitis have been on the rise in the U.S. (iStock photo)
Diverticulitis, a disabling colon problem that can cause pain, obstruction and fever, became more common in the U.S. from the late 1990s to the mid-2000s, a new study suggests.
The findings are from one Minnesota county, but other research indicates that hospitalizations for diverticulitis also increased in the U.S. generally during this period.
The overall incidence of diverticulitis, with or without hospitalization, increased by 50 percent since 2000, and more so in younger people, said lead author Dr. Adil E. Bharucha of the Mayo Clinic in Rochester, Minnesota.
So-called diverticula, which are small pouches along the large intestine, become more common with age. The presence of these pouches is called diverticulosis. If the pouches become inflamed or infected, the condition is called diverticulitis.
According to the American Society for Gastrointestinal Endoscopy, half of all people in the U.S. over age 60, and nearly everyone over age 80, has at least some diverticula in their colon.
In the vast majority of patients, if diverticulitis does develop, it's minor and can be treated with a short course of antibiotics, Bharucha told Reuters Health by email. "Some patients will have symptoms of irritable bowel syndrome after the diverticulitis resolves," he said.
He and his coauthors used the Rochester Epidemiology Project to study the records of all diagnoses of diverticulitis in Olmsted County, Minnesota, between 1980 and 2007.
In this time period, 3,222 people were diagnosed with diverticulitis, 56 percent of them women, at an average age of 62 years.
Between 1980 and 1989 the incidence rate was 115 cases per 100,000 people per year, which increased to 188 cases by 2000 to 2007.
While the problem was more common in older people, cases in younger people increased over time, the authors write in the American Journal of Gastroenterology.
The 12 percent complication rate did not change over time, nor did the incidence of surgery.
Experts do not know why the incidence of diverticulitis has been on the rise, Bharucha said.
Obesity may be one risk factor for the condition, and obesity has also become more common in recent decades, which may partly explain the trend, he said.
"More than one-third of adults are now considered to be obese," said Dr. Anne Peery, who studies risk factors for diverticular disease at the University of North Carolina at Chapel Hill School of Medicine.
"Given these trends, it's not surprising that the incidence of diverticulitis is rising," Peery told Reuters Health by email. She was not part of the new research.
Most patients with diverticulitis are unable to work or perform their day-to-day actives, she said.
"It's an unpredictable disease and that can be a source of significant stress," Peery said.
These results are helpful to providers in that they confirm the earlier finding that complications like abscess or perforation are more likely to happen with a first instance of diverticulitis, rather than with recurrent disease, she said.
"Traditionally, low intake of dietary fiber has been implicated (as a) cause of diverticulitis," but the role of diet is still unclear, Bharucha said. "As always, it helps to quit smoking, exercise, lose weight, and to avoid using aspirin and non-steroidal anti-inflammatory drugs (NSAIDs) if possible."
But no one really knows exactly what causes the disease, Peery said.