title: Early elevation of albumin excretion rate is associated with poor gluten-free diet adherence in young people with coeliac disease and diabetes.
abstract: OBJECTIVE
  There are conflicting data on microvascular complications in coexisting Type 1 diabetes and coeliac disease. We compared complications rates in youth with or without coeliac disease and examined the association between gluten-free diet adherence and complications.
  
  
  METHODS
  This was a comparative study of adolescents (2510 without coeliac disease, 129 with coeliac disease); 60 (47%) did not adhere to a gluten-free diet--defined as elevated anti-tissue transglutaminase or endomysial immunoglobulin A titres. Retinopathy was detected using 7-field fundal photography and albumin excretion rate by timed overnight urine collections, with early elevation defined as albumin excretion rate ≥ 7.5 μg/min. Logistic regression was used to examine the association between complications and explanatory variables, including coeliac disease vs. no coeliac disease, gluten-free diet adherence vs. non-adherence, diabetes duration and HbA1c .
  
  
  RESULTS
  Median age at last assessment was 16.5 years. Those with coeliac disease vs. those without were younger at diabetes diagnosis (7.1 vs. 8.6 years, P < 0.001) and had longer diabetes duration (9.3 vs. 7.2 years, P < 0.001). HbA1c was lower in those with coeliac disease vs. those without (67 vs. 70 mmol/mol, 8.3 vs. 8.6%, P = 0.04) and adherence to a gluten-free diet vs. non-adherence (66 vs. 72 mmol/mol, 8.2 vs. 8.7%, P = 0.003). There were no differences in complication rates between those with coeliac disease vs. those without (retinopathy 22 vs. 23%, elevated albumin excretion rate 31 vs. 28%). Non-adherence to a gluten-free diet was associated with elevated albumin excretion rate (40 vs. 23%, P = 0.04). In multivariable logistic regression, elevated albumin excretion rate was associated with non-adherence to a gluten-free diet (odds ratio 2.37, 95% CI 1.04-5.40, P = 0.04) and diabetes duration (odds ratio 1.13, 95% CI 1.02-1.25, P = 0.03), but not HbA1c .
  
  
  CONCLUSIONS
  While glycaemic control is better in patients with coeliac disease, non-adherence to a gluten-free diet is associated with elevated albumin excretion rate. The possible protection of a gluten-free diet on complications warrants further investigation.
authors.affiliation: Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead; Discipline of Paediatrics and Child Health, University of Sydney, Sydney.
authors.forename: A
authors.initials: A
authors.lastname: Pham-Short
authors.forename: K
authors.initials: K
authors.lastname: C Donaghue
authors.forename: G
authors.initials: G
authors.lastname: Ambler
authors.forename: A
authors.initials: A
authors.lastname: K Chan
authors.forename: S
authors.initials: S
authors.lastname: Hing
authors.forename: J
authors.initials: J
authors.lastname: Cusumano
authors.forename: M
authors.initials: M
authors.lastname: E Craig
mesh_terms: D000293:Adolescent; D000418:Albumins / Q000378:metabolism*; D000419:Albuminuria / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000652:urine; D002446:Celiac Disease / Q000150:complications / Q000178:diet therapy* / Q000453:epidemiology* / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000178:diet therapy / Q000453:epidemiology* / Q000378:metabolism; D055050:Diet, Gluten-Free; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data*
chemical_list: D000418:Albumins; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human