Earlier research indicated that higher childhood socioeconomic status and delayed infection with the prevalent Epstein-Barr virus were important predictors of Hodgkin's lymphoma in young adulthood. Because attending nursery school or day care favors earlier exposure to common childhood infections, the study supports the hypothesis that delayed infection increases the risk of young-adult Hodgkin's lymphoma, but fails to uphold the link to socioeconomic factors. The research also shows that Hodgkin's lymphoma among adults aged 55 and over is associated with lower socioeconomic status, but not preschool attendance, indicating the existence of a separate mechanism for the development of Hodgkin's lymphoma in the two age groups.

"Years of epidemiological evidence have linked the risk of Hodgkin's lymphoma among young adults to high maternal education, few siblings, low housing density, and other aspects of higher childhood socioeconomic status," noted lead author Ellen T. Chang, Sc.D., of the Harvard School of Public Health. "It has been believed that these characteristics postpone childhood exposure to common pathogens, including the usually harmless Epstein-Barr virus, which can cause infectious mononucleosis when infection is delayed until adolescence. Infectious mononucleosis is a demonstrated risk factor for Hodgkin's lymphoma. However, we found no association between any of these factors and Hodgkin's lymphoma risk."

Chang went on to explain that how and when a child's immune system matures, as well as changes in the social environment of preschool aged children in the United States, account primar
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Contact: Elizabeth J. Tait
tait@aacr.org
215-440-9300
American Association for Cancer Research
6-Aug-2004