The effect of biopsy‐positive silent coeliac disease and treatment with a gluten‐free diet on growth and glycaemic control in children with Type 1 diabetes

Objective To determine the effect of coeliac disease and treatment with a gluten‐free diet on growth and glycaemic control in asymptomatic children with Type 1 diabetes. Methods Data were compared in children with coeliac disease diagnosed by annual antibody screening and jejunal biopsy and treated with a gluten‐free diet (n = 49) against individuals who were antibody negative (n = 49) matched for age, sex and duration of diabetes. Results No differences in growth were observed. In the years prior to diagnosis of coeliac disease, mean glycated haemoglobin (HbA_1c) was lower in cases compared with control subjects [8.3 ± 1.1% vs. 8.7 ± 0.9%, P = 0.02 (mean ± sd )]. In cases, HbA_1c deteriorated 12 months from the start of a gluten‐free diet to levels similar to control subjects (8.9 ± 1.5% vs. 8.8 ± 1.5%, P‐value for analysis of variance = 0.9). In regression analysis, the diagnosis of coeliac disease and start of a gluten‐free diet was associated with a rise in HbA_1c in the first year of treatment [odds ratio 1.56 (95% confidence intervals 1.16–2.10), P = 0.003] after adjusting for insulin dose and regimen and other variables. Conclusions In children with Type 1 diabetes, lower HbA_1c prior to diagnosis of silent coeliac disease rises following treatment with a gluten‐free diet to levels similar to those without coeliac disease. Although unproven, these observations may relate to abnormalities at the small bowel mucosa before the appearance of circulating coeliac antibodies.