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 (HbA1c) was lower in cases compared with control subjects [8.3 ± 1.1% vs. 8.7 ± 0.9%, P = 0.02 (mean ± sd)]. In cases, HbA1c 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 HbA1c 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 HbA1c 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.