NEW YORK (Reuters Health) – Celiac disease is 4 times more common now than it was in the 1950’s, according to researchers at the Mayo Clinic in Rochester, Minnesota.

Their conclusion results from a study in which they had access to frozen blood samples that had been drawn between 1948 and 1954 from 9133 healthy young Air Force personnel. The investigators tested these samples for the presence of celiac disease autoantibodies and then compared the results with their findings in two other gender-matched cohorts: 5558 present-day residents of Minnesota born in the same years as the earlier cohort, and 7210 present-day Minnesota residents who are now the same ages as the frozen-sample donors were in 1948-1954.

In the July issue of Gastroenterology, lead author Dr. Alberto Rubio-Tapia and his colleagues report that 14, or 0.2%, of the subjects who provided blood samples roughly 60 years ago had undiagnosed celiac disease. In contrast, the rate of undiagnosed celiac disease was 0.8% in the current subjects with similar years of birth as the1948-1954 cohort (with 46 cases of undiagnosed celiac disease) and 0.9% in the current subjects with similar age at sampling (with 68 undiagnosed celiacs).

In other words, “the prevalence of celiac disease has dramatically increased more than four-fold in the United States during the past 50 years,” the researchers said. Similar increases have been reported in Europe, they added.

Dr. Rubio-Tapia’s team also found that among the volunteers in the 1948-1954 study, all-cause mortality during the next 45 years was nearly four times higher for people with undiagnosed celiac disease than for those who were seronegative (hazard ratio 3.9).

In a press release from the Mayo Clinic, senior author Dr. Joseph Murray commented, “Some studies have suggested that for every person who has been diagnosed with celiac disease, there are likely 30 more who have it but are not diagnosed. And given the nearly quadrupled mortality risk for silent celiac disease we have shown in our study, getting more patients and health professionals to consider the possibility of celiac disease is important.”

“Moreover,” the research team concludes, “our finding that the prevalence of celiac disease seems to have increased dramatically during the past 50 years suggests that celiac disease is emerging as a substantial public health concern in the United States.”

“The reasons for the increasing prevalence of celiac disease over time will need further study,” Dr. Rubio-Tapia told Reuters Health. “Human genetic changes are extremely slow, unlikely to happen in only 50 years, thus the most likely explanation may be environmental.”

Dr. Rubio-Tapia also cited what is sometimes referred to as the “hygiene hypothesis,” noting that “changing patterns of childhood infection as a consequence of a cleaner environment may also affect the prevalence of celiac disease (and other autoimmune diseases),” leading to fewer infections but more allergic and/or autoimmune diseases. “Recent data from Europe support this theory in celiac disease,” Dr. Rubio-Tapia pointed out. “The prevalence of celiac disease was lower in Russian Karelia (on the border with Finland) with inferior prosperity and (standards of hygiene) than in Finland.”

“However,” he continued, “I think that the ‘hygiene hypothesis’ is likely only a partial explanation because celiac disease is a global health problem that affects both developed and developing countries…. Also, there is evidence that certain infections such as rotavirus may increase the risk of celiac disease in genetically predisposed individuals. So, the interaction between humans and infectious microorganisms is very complex and certainly different in each person.”

“Finally,” Dr. Rubio-Tapia said, “as celiac disease is triggered by gluten, we can speculate that maybe some changes in gluten such as patterns of consumption, processing or preparation of gluten-containing foods might be factors; however, extensive scientific evidence are lacking and (any such change) remains to be proven experimentally.”

Ultimately, Dr. Rubio-Tapia concluded, “the increasing prevalence of celiac disease over time may be the result of several of (these) factors acting together to cause damage of the intestine in genetically susceptible persons.”

Reference:
Gastroenterology 2009;137:88-93.