Day Care May Cut Leukemia Risk

Exposure To More Children — And More Infections — Could Be Reason

(WebMD)  In the current study, Gilham looked at 3,800 children with cancer. Some of the kids had leukemia — either ALL or another type — and some had other forms of cancer. They were between 2 and 5 years old when they were diagnosed. Social activity and day care habits were compared with 7,600 children without cancer.


Formal Day Care Protects Most

Interaction with an older infant at least once a week that did not live in the same home was associated with a 34 percent decreased risk of ALL. Protection from other types of leukemia was similar.

When other types of cancer were taken together there was also a similar level of protection. However, when individual types of cancer were evaluated, risk was decreased only for central nervous system cancers, such as brain cancer.

When the results were looked at more closely, the researchers discovered that the protection from social activity mostly stemmed from formal day care. This included kids who attended day care for any amount of time, a playgroup at least two half-days a week, or at least two half-days a week in a smaller childcare setting with at least four children.

The more social activity or day care the child was exposed to, the lower the risk of ALL. The effect was most pronounced when the child attended day care within the first three months of life.


Infection Important For Child Health

Gilham's study is published in BMJ Online First. Gilham is a statistician at the Institute of Cancer Research in Sutton, England.

The researchers say that some degree of early exposure to infection seems to be important for child health. However, they add that more research is needed to determine the true effect and if the link is associated with any particular infection.

Sources: Gilham C. BMJ Online First; pp 1-6. National Cancer Institute.