Coeliac disease characteristics, compliance to a gluten free diet and risk of lymphoma by subtype

Objective: Coeliac disease is associated with an increased risk of malignant lymphomas. We investigated the importance of coeliac disease characteristics and diet compliance for risk of lymphoma. Methods: In a nested case-control design, we identified 59 patients with lymphoma and 137 matched controls from a population-based cohort of 11,650 inpatients with coeliac disease. We assessed coeliac disease characteristics at diagnosis and dietary compliance collected prospectively from medical records during follow-up. Results: Poor compliance was not significantly associated with risk of lymphoma overall (odds ratio 1.83, 95% confidence interval 0.78-4.31) nor of lymphoma subtypes. Risk estimates differed by subtype; risk of T-cell lymphoma (odds ratio 1.01, confidence interval 0.32-3.15) or intestinal lymphoma (odds ratio 0.66, confidence interval 0.17-2.56) was unelevated, whereas there was an indication of a risk increase of B-cell lymphoma (odds ratio 4.74, confidence interval 0.89-25.3) or extraintestinal lymphoma (odds ratio 3.00, confidence interval 0.73-12.3) following poor compliance. History of weight loss (odds ratio 2.89, confidence interval 1.00-8.29) at coeliac disease diagnosis was associated with an increased risk of lymphoma when excluding tumours occurring with short latency (<3 years). Conclusions: Compliance to a gluten-free diet did not significantly alter lymphoma risk, but a moderate effect cannot be excluded. Weight loss, a potential marker of coeliac disease severity, may be associated with lymphoma risk. (C) 2011 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.