Type 1 and type 2 diabetes in celiac disease: prevalence and effect on clinical and histological presentation

BACKGROUND Association between celiac disease and type 1 diabetes in adults is still somewhat unclear, and that between celiac disease and type 2 diabetes even less known. We studied these issues in a large cohort of adult celiac disease patients. METHODS The prevalence of type 1 and type 2 diabetes in 1358 celiac patients was compared with the population-based values. Furthermore, patients with celiac disease and concomitant type 1 or type 2 diabetes and those with celiac disease only underwent comparisons of clinical and histological features and adherence to gluten-free diet. RESULTS The prevalence of type 1 diabetes (men/women) was 8.0 % /1.8 % in celiac patients and 0.7 % /0.3 % in the population, and that of type 2 diabetes 4.3 % /2.5 % and 4.4 % /3.0 %, respectively. Celiac patients with concomitant type 1 diabetes were younger (45 years vs 65 years and 52 years, P < 0.001) and more often screen-detected (43 % vs 13 % and 14 %, P < 0.001), had less other gastrointestinal diseases (8 % vs 40 % and 25 %, P = 0.028), more thyroidal diseases (18 % vs 16 % and 13 %, P = 0.043) and lower dietary adherence (71 % vs 95 % and 96 %, P < 0.001) compared with celiac patients with concomitant type 2 diabetes and patients with celiac disease only. Patients with concomitant type 2 diabetes had more hypercholesterolemia than the other groups (8 % vs 6 % and 4 %, P = 0.024), and both diabetes groups more hypertension (47 % and 31 % vs 15 %, P < 0.001) and coronary artery disease (29 % and 18 % vs 3 %, P < 0.001) than the patients with celiac disease only. CONCLUSIONS Type 1 diabetes was markedly overrepresented in celiac disease, especially in men, whereas the prevalence of type 2 diabetes was comparable with the population. Concomitant type 1 or type 2 diabetes predisposes celiac patients to severe co-morbidities and type 1 diabetes also to poor dietary adherence.