Autoimmune disease is a risk factor for the development of non-Hodgkin's lymphoma.

Objective: To investigate the relationship of prior autoimmune disease to the development of non-Hodgkin's lymphoma (NHL).

Methods: Patients with NHL (n = 278) seen from 1993 to 2002 were compared with a group of patients with other hematological disorders (controls, n = 317) seen at the same time. All patients were questioned about prior autoimmune disease. Comparisons between NHL patients and controls were based on analysis of a 2 2 table of counts using Fisher's exact test. Analysis of the effect of autoimmune disease on NHL status, controlling for other risk factors, was performed using logistic regression.

Results: Thirty-six (13%) NHL patients had a prior autoimmune disease compared to 5% of controls (p = 0.001). Sixty-nine percent of NHL patients with a prior autoimmune disease were female compared to 43% without a prior autoimmune disease, and this was similar in control patients, 69% and 48%, respectively. Twenty percent of all women with NHL had a history of autoimmune disease compared to 7% of women in the control group (p = 0.001). Nineteen of the NHL patients with autoimmune disease (56%) received immunosuppressive treatment compared to 5 (38%) in the controls.

Conclusion: Autoimmune disease may account in part for the increase in NHL, especially in women.