Blood transfusion and risk of non-Hodgkin's lymphoma in Connecticut women.

The incidence and mortality rates of non-Hodgkin's lymphoma have been increasing worldwide. Allogeneic blood transfusion has been suggested as a risk factor for non-Hodgkin's lymphoma, but the results from epidemiologic studies have been inconsistent. Data from a population-based case-control study of Connecticut women were analyzed to evaluate this relation. A total of 601 histologically confirmed, non-Hodgkin's lymphoma incident cases identified between 1996 and 2000 and 717 randomly selected controls were included in this study. Allogeneic blood transfusion was not associated with the increased risk of non-Hodgkin's lymphoma overall (odds ratio = 1.0, 95% confidence interval: 0.7, 1.3) or by subtype of the disease. The risk also did not vary by number of allogeneic blood transfusions, age at first transfusion, or time since first transfusion. When the reason for blood transfusion was considered, an increased risk of non-Hodgkin's lymphoma was found only for allogeneic blood transfusion for reason of anemia. In summary, the authors' findings do not support the hypothesis that allogeneic blood transfusion increases the risk of non-Hodgkin's lymphoma.