Celiac disease ‘frequently’ asymptomatic in type 1 diabetes
Celiac disease as a comorbidity of type 1 diabetes is often asymptomatic, and people with both diseases should closely monitor glucose levels during transition to a gluten-free diet, according to a study.
“Celiac disease is a disorder triggered by gluten that is frequently unrecognized and asymptomatic, especially in individuals with type 1 diabetes or other autoimmune conditions,” Farid Mahmud, MD, FRCPC, associate professor and clinician investigator in the division of endocrinology at the Hospital for Sick Children at the University of Toronto, told Healio. “A significant challenge faced by clinicians relates to absence of evidence to assess the benefits and harms of screening and treatment in asymptomatic persons, especially in the context of type 1 diabetes.”
In the Celiac Disease and Diabetes-Dietary Intervention and Evaluation Trial, Mahmud and colleagues screened for celiac disease among 1,298 adults and 1,089 children with type 1 diabetes and no symptoms of the condition, such as weight or growth changes, gastrointestinal symptoms or anemia. The researchers identified 51 participants with biopsy-positive celiac disease and randomly assigned 27 to a gluten-free diet and 24 to a regular diet containing gluten for 1 year. HbA1c was evaluated at baseline and 6 and 12 months and postprandial glucose levels with continuous glucose monitoring. Participants in the regular-diet group who became symptomatic for celiac disease during the study were transitioned to a gluten-free diet.
The primary outcome of was change in HbA1c from baseline to 12 months.
Among the entire cohort, more pediatric than adult participants had undergone previous serologic screening for celiac disease, 43.6%vs. 6.9%, respectively, and adult participants had higher celiac disease-seropositivity rates (6.8% vs. 4.7%).
“The higher rates of asymptomatic celiac disease observed in adults were surprising and reflective of lower rates of prior screening overall. ... This may reflect a misperception of celiac disease as a condition exclusively seen during the pediatric period,” Mahmud said.
The two diet groups had similar HbA1c levels and ranges for hypoglycemia, euglycemia and hyperglycemia during the study. However, the gluten-free group experienced higher 2-hour (P = .0015) and 4-hour (P = .014) postprandial glucose excursions vs. the regular-diet group, which experienced a return to premeal levels at 4 hours. In the gluten-free diet group, there was a 0.3% increase in HbA1c over 12 months (P = .028).
According to Mahmud, clinicians be aware that celiac disease is an important autoimmune comorbidity in patient with type 1 diabetes and that clinical vigilance is warranted during transition to a gluten-free diet.
“It’s also important to recognize that while we did see glycemic variability with the [gluten-free diet] in the short term, there is a need for longitudinal studies to further assess the clinical impact of this ‘double diagnosis’ to better understand potential benefits and risks of treatment in asymptomatic individuals with type 1 diabetes.” Mahmud said.