Taking aspirin or ibuprofen daily for at least five years may increase women’s risk of breast cancer, a California teacher study indicates.
However, the research team said it was not certain if the risk is merely “casual,” particularly since its massive study found no increased risk of breast cancer for shorter-term, less frequent use of the non-steroidal anti-inflammatory drugs, or NSAIDs.
For the long-term use, women who took aspirin were 80 percent more likely to develop breast cancer while women who took ibuprofen were 50 percent more likely to develop the disease.
The findings were the opposite of other recent studies.
The team reported results of its study of 114,460 California teachers in the Journal of the National Cancer Institute.
Lead researcher Sarah Marshall of the University of Southern California said she had expected the NSAIDs to reduce the risk of breast cancer.