Potential reno-protective effects of a gluten-free diet in type 1 diabetes

Coeliac disease is common in type 1 diabetes. It is managed with a gluten-free diet, characterised by foods low in AGEs. We hypothesised that this diet would lead to lower plasma AGEs and be associated with reduced albuminuria. From a single paediatric clinic, we recruited 21 children with type 1 diabetes and biopsy-proven coeliac disease, and 38 individuals with diabetes alone. The groups were matched for age, sex, duration of disease and metabolic control. Participants completed a detailed clinical and dietary history. Blood samples were taken for HbA(1c), coeliac serology, thyroid function, serum IgA levels and plasma AGEs, and urine samples were obtained for estimation of the albumin/creatinine ratio (ACR). All the individuals with coeliac disease were asymptomatic, with negative transglutaminase antibodies. There were no significant differences between the groups in terms of age (14 years), sex (29% male), duration of diabetes (7 years), mean HbA(1c) (8.3%), lipid levels or treatment regimens. However, children with diabetes and coeliac disease had twofold lower levels of urinary ACR than with those diabetes alone (p = 0.04). This was associated with lower levels of circulating AGEs (p = 0.03). These associations were independent of metabolic control, diabetes management and other potentially confounding variables, such as household exposure to cigarette smoke. Adherence to a gluten-free diet may provide additional benefits for individuals with coeliac disease, and potentially those with type 1 diabetes.