Up to a decade after diagnosis, some people with celiac disease are still anemic

Anemia sometimes continues even for those on the gluten-free diet whose intestines have healed

By Amy Ratner, director of scientific affairs

Even after a decade on the gluten-free diet, some adults and children with celiac disease continue to be anemic, a recent study by researchers in Italy has found.

In adults, nearly 18 percent were anemic after eight to 10 years on the diet, compared to 24 percent at diagnosis. Meanwhile, more than 4 percent of children were anemic after eight to 10 years, compared to about 6 percent at diagnosis.

Anemia is one of the most common symptoms outside of intestinal problems reported by patients at diagnosis and can be the only sign of celiac disease.

Anemia is due mainly to the lack of iron absorption. Celiac disease affects the part of the intestine that absorbs iron from the diet, explaining why iron-deficiency anemia is a frequent symptom of celiac disease in both children and adults, says the study published in the journal BMC Gastroenterology.

How the study was done

The study was based on a review of medical records of 184 adults and 127 children at three points in time: at diagnosis and three to five years and eight to 10 years later. Researchers reviewed medical test results that showed hemoglobin, iron, folate and vitamin B12 levels. The study participants were patients with celiac disease seen at the University Hospital of L’Aguila.

Women were more likely than men to be anemic at diagnosis, in part because the average age of study participanatas suggests many of the women were still having menstrual periods. Children with anemia at diagnosis were likely to be younger than those who were not anemic, and they more commonly had iron deficiency. This could be because younger children often have a more severe case of celiac disease than older children, the study suggests.

Researchers reviewed how often and how severely patients suffered from anemia by looking at the concentration of hemoglobin. Hemoglobin is a protein found in red blood cells, and low levels can be a sign of anemia.

Overall, hemoglobin levels increased over time, but not enough to remedy anemia quickly. After three to five years on the diet, anemia remained a stubborn symptom.

Anemia persists

The decrease in the percentage of adults with anemia at eight to 10 years was significant, the study says. However, at eight to ten years, nearly one-fifth of adult patients who had healing of the intestine and an increase of hemoglobin remained anemic.

The study partially disproves the idea that healing of the intestine alone is enough to resolve anemia, the authors note.

The study suggests that anemia persists in adults more frequently because they have a longer delay in diagnosis and pronounced damage to the very tiny structure of the cells of the lining of the intestine. This damage, which would lead to some impairment of iron absorption, could persist even when the intestine shows healing.

Overall anemia might be less common in children than adults because children have faster and more complete intestinal healing on the gluten-free diet, the study hypothesizes. Rapid healing in children could be traced to quicker diagnosis and more strictly following the diet, the study says.

Other potential causes of anemia related to iron deficiency for those with celiac disease on a gluten-free diet include not following the diet closely, inadvertently being exposed to gluten through cross-contact and a gluten-free diet that is low in iron.

The length of the study was one of its strengths, while the low percentage of data available for both follow-up points was one of its limitations.

You can read more about the study here.