Non-adherence to a gluten free diet (GFD) could lead to persistent villous atrophy and the development of complications in coeliac disease. However, current adherence assessment methods have their own limitations: dietetic evaluation by a specialist dietitian is usually accurate but resources are often limited; serology has been shown to have poor sensitivities in measuring adherence; and although duodenal biopsies are considered the gold standard, it is invasive and expensive. We aimed to assess the sensitivities of 2 validated questionnaires, which have been suggested as non-invasive markers of adherence.Methods
We prospectively recruited coeliac disease patients who were referred to secondary care for further evaluation of dietary adherence and disease remission. All patients were tested with tissue transglutaminase (IgA-TTG) and endomysial antibodies (IgA-EMA), and completed 2 adherence questionnaires, one devised by Biagi et al.,1 and Coeliac Disease Adherence Test (CDAT) devised by Leffler et al.2 The questions were largely related to the patients’ attitude and strategy towards gluten avoidance. The Biagi questionnaire consists of 4 questions, and the score ranges from 0–4; score <3 indicates non-adherence. CDAT consists of 7 questions, and the score ranges from 7–35; score >13 indicates non-adherence. Duodenal biopsies were taken from all patients, and the presence/absence of villous atrophy was the reference standard used to determine the sensitivities.Results
A total of 120 patients were recruited, 80 females (67%), median age 54, median duration of GFD 5 years. Forty-five patients (37.5%) had persistent villous atrophy. The median CDAT score was 12, and the median Biagi score was 3. The sensitivities of the surrogate markers for adherence compared to duodenal histology are demonstrated below.Conclusions
CDAT alone was not superior compared to IgA-TTG (p=0.6961). However, the combination of CDAT and Biagi questionnaires significantly outperformed IgA-TTG (p=0.0162) in detecting villous atrophy. These questionnaires could potentially provide an immediate reflection of dietary adherence, although the sensitivities remain suboptimal and cannot replace histological assessment.