Diabetes and risk of non-Hodgkin lymphoma: A case-control study

Aims and background: We investigated the relation between diabetes and the risk of non-Hodgkin lymphoma, as epidemiological results are controversial and diabetes has been related to the risk of several neoplasms. Patients and methods: We analyzed the combined dataset of two Italian case-control studies conducted in 1985-1997 and 1999-2002. Cases were 671 patients, aged <85 years, with incident, histologically confirmed non-Hodgkin lymphoma, and controls were 1799 patients admitted to hospitals for acute nonneoplastic conditions. Odds ratios were estimated using unconditional multiple logistic regression models including terms for age, center, sex, residence and educational level. Results: No material association between diabetes and non-Hodgkin lymphoma risk was observed, with an odds ratio of 1.12 (95% confidence intervals, 0.70-1.77). No association was found in relation to age at first diagnosis of diabetes, years since diagnosis, or in younger and older subjects at diagnosis of non-Hodgkin lymphoma. Conclusions: The results of the study allow to exclude a strong association between diabetes and non-Hodgkin lymphoma, although the small number of cases with diabetes leaves open the possibility of a moderate direct relation.