The number of cases of celiac disease, an immune-system reaction to dietary gluten, has increased more than fourfold in the past 50 years, according to a report from the Mayo Clinic.

The study also found that subjects who did not know they had celiac disease were nearly four times more likely than celiac-free subjects to die during 45 years of follow-up.

“Celiac disease has become much more common in the past 50 years, and we don't know why,” says Joseph A. Murray, MD, the Mayo Clinic gastroenterologist who led the study. “[The diorder] now affects about one in a hundred people.

“We have also shown that undiagnosed or ‘silent' celiac disease may have a significant impact on survival. The increasing prevalence, combined with the mortality impact, suggests celiac disease could be a significant public health issue.”

The Mayo team first tested blood samples from 9,133 healthy young adults at Warren Air Force Base in Wyoming between 1948 and 1954 for the antibody that people with celiac disease produce in reaction to gluten. The results were then compared with two recently collected gender-matched cohorts from Olmsted County, Minn.

Researchers found that young people today are greater than 4.5 times more likely to be diagnosed with celiac disease than their counterparts in the 1950s (Gastroenterology. 2009; 137:88-93).

“Our results confirm recent data showing that undiagnosed celiac disease is associated with significant excess mortality over time,” the researchers conclude. “Thus early detection and treatment of presymptomatic celiac disease seem logical if we assume that strict adherence to a gluten-free diet has the same positive effect on undiagnosed celiac disease as previously shown in symptomatic celiac disease.”

The findings indicate the need for heightened awareness among both patients and clinicians. “Celiac disease is unusual, but it's no longer rare,” Dr. Murray explains. “Until recently, the standard approach to finding celiac disease has been to wait for people to complain of symptoms and to come to a clinician for investigation. This study suggests that we may need to consider looking for celiac disease in the general population, more like we do in testing for cholesterol or BP.”