Metabolic syndrome in patients with coeliac disease on a gluten-free diet.

BACKGROUND: Several studies have shown that weight changes are common in patients with coeliac disease after starting a gluten-free diet (GFD), but data on the prevalence of metabolic syndrome in this population are still scarce. AIMS: To assess the prevalence of metabolic syndrome in patients with CD at diagnosis and 1 year after starting GFD. METHODS: We enrolled all consecutive patients with newly diagnosed coeliac disease (CD) who were referred to our third-level CD Unit. For all patients we collected: waist circumference, BMI, blood pressure, lipid profile (HDL cholesterol, triglycerides) and levels of blood glucose. Diagnosis of metabolic syndrome was made according to the International Diabetes Federation (IDF) criteria for European countries. The prevalence of metabolic syndrome was re-assessed after 12 months of GFD. RESULTS: Ninety-eight patients with CD were assessed, two patients with CD (2%) fulfilled the diagnostic criteria for metabolic syndrome at diagnosis and 29 patients (29.5%) after 12 months of GFD (P < 0.01; OR: 20). With regard to metabolic syndrome sub-categories 1 year after GFD compared to baseline respectively: 72 vs. 48 patients exceeded waist circumference cut-off (P < 0.01; OR: 2.8); 18 vs. 4 patients had high blood pressure (P < 0.01; OR: 5.2); 25 vs. 7 patients exceeded glycemic threshold (P = 0.01; OR: 4.4); 34 vs. 32 patients with CD had reduced levels of HDL cholesterol (P = 0.7); and 16 vs. 7 patients had high levels of triglycerides (P = 0.05). CONCLUSIONS: Patients with coeliac disease show a high risk of metabolic syndrome 1 year after starting a gluten-free diet. We suggest that an in-depth nutritional assessment is undertaken for all patients with coeliac disease.

The presence of anti-endomysial antibodies and the level of anti-tissue transglutaminases can be used to diagnose adult coeliac disease without duodenal biopsy.

BACKGROUND: The new ESPGHAN guidelines for diagnosis of paediatric coeliac disease suggest to avoid biopsy in genetically pre-disposed and symptomatic individuals with positive anti-endomysial antibodies (EMA) and anti-tissue transglutaminases (a-tTG). However, duodenal biopsy remains the gold standard in adult coeliac disease. AIMS: To establish the cut-off values of a-tTG, which would: predict the presence of duodenal histology (Marsh ≥2) diagnostic for coeliac disease; and predict the presence of villous atrophy (Marsh 3) in adults. METHODS: We performed an observational prospective study including all consecutive adult patients with suspected coeliac disease. All subjects were tested for EMA and a-tTG. Coeliac disease diagnosis was made in presence of Marsh ≥2, a-tTG >7 U/mL and positive EMA. A ROC curve was constructed to establish the best specificity cut-off of a-tTG levels, which would predict the presence of Marsh ≥2 and Marsh 3 at histology. RESULTS: The study included 310 patients with positive antibodies. Histology showed Marsh 1 in 8.7%, Marsh 2 in 3.5%, Marsh 3 in 87.7%. The best cut-off value of a-tTG for predicting Marsh ≥2 was 45 U/mL (sensitivity 70%; specificity 100%; PPV 100%; NPV 24.1%); the best cut-off for predicting villous atrophy was 62.4 U/mL (sensitivity 69%, specificity 100%; PPV 100%; NPV 31%). CONCLUSIONS: The diagnosis of coeliac disease can be reached without histology in adult patients with positive EMA and a-tTG levels >45 U/mL. An a-tTG level >62.4 was diagnostic for villous atrophy. These results could contribute to improving the diagnosis of coeliac disease by allowing for a significant reduction in diagnosis-related costs.