NEW YORK (Reuters Health) – The incidence of non-Hodgkin’s lymphoma (NHL) is increased somewhat in patients with diabetes, according to results of a meta-analysis published in Diabetes Care for December.

“Although the relative risk is moderate, given the rapidly increasing incidence and prevalence of diabetes, the number of incident cases of NHL attributed to diabetes can potentially be very high,” senior author Dr. Anastassios G. Pittas, at Tufts University School of Medicine in Boston, and colleagues point out.

Dr. Pittas’ team conducted a Medline search for studies reporting an association between diabetes and NHL. Their search turned up 5 prospective cohort studies and 11 case-control studies.

The prospective cohort studies, published since 1971, had mean follow-up periods ranging from 7 to 24 years and involved more than 160,000 diabetics and 337 incident cases of NHL. The 11 case-control studies published since 1988 involved 382 cases of NHL among 4844 patients with diabetes and 7974 cases of NHL among 86,660 controls.

Combined data from all studies showed the risk ratio of NHL in patients with diabetes was 1.19. Among prospective studies, the RR for NHL among patients with diabetes was 1.41, while the increased risk was not statistically significant in the case-control studies (RR 1.12).

Dr. Pittas and associates point out that the incidence of NHL has increased since 1950 and is commonly associated with conditions characterized by immune dysregulation.

Furthermore, they note, diabetes is “characterized by immune dysfunction related to impaired neutrophil activity and changes in cellular and humoral immunity, which may, at least in part, account for the increased risk of NHL that we found in this study.”

Reference:
Diabetes Care 2008;31:2391-2397.