COLUMBUS, Ohio - New research adds to the growing body of evidence suggesting that there's a link between allergies and reduced risk of a serious type of cancer that starts in the brain. This study suggests the reduced risk is stronger among women than men, although men with certain allergy profiles also have a lower tumor risk.
The study also strengthens scientists' belief that something about having allergies or a related factor lowers the risk for this cancer. Because these tumors, called glioma, have the potential to suppress the immune system to allow them to grow, researchers have never been sure whether allergies reduce cancer risk or if, before diagnosis, these tumors interfere with the hypersensitive immune response to allergens.
Scientists conducting this study were able to analyze stored blood samples that were taken from patients decades before they were diagnosed with glioma. Men and women whose blood samples contained allergy-related antibodies had an almost 50 percent lower risk of developing glioma 20 years later compared to people without signs of allergies.
"This is our most important finding," said Judith Schwartzbaum, associate professor of epidemiology at Ohio State University and lead author of the study. "The longer before glioma diagnosis that the effect of allergies is present, the less likely it is that the tumor is suppressing allergies. Seeing this association so long before tumor diagnosis suggests that antibodies or some aspect of allergy is reducing tumor risk.
"It could be that in allergic people, higher levels of circulating antibodies may stimulate the immune system, and that could lower the risk of glioma," said Schwartzbaum, also an investigator in Ohio State's Comprehensive Cancer Center. "Absence of allergy is the strongest risk factor identified so far for this brain tumor, and there is still more to understand about how this association works."
Many previous studies of the link
|Contact: Judith Schwartzbaum|
Ohio State University