Three years ago, Angelina Jolie announced in a New York Times op-ed that she'd had a preventive double mastectomy after testing positive for mutations in the BRCA1 gene, which put her at an increased risk of breast and ovarian cancers.
The article went hugely viral, and became a flashpoint in the debate about breast cancer risk and prevention. It also spurred a bunch of researchers to study what impact Jolie's decision might have on mastectomy rates and testing for the cancer-causing BRCA1 and 2 genetic mutations.
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In the latest paper, published in the BMJ, researchers from Harvard looked at insurance data from nearly 10 million women before and after Jolie's May 2013 editorial.
In the two weeks following the article, they found that BRCA testing rates shot up by 65 percent. But mastectomy rates remained unchanged in the months after that. This suggests, they wrote, that "BRCA tests obtained as a result of the Jolie editorial did not yield additional BRCA positive mutations that might warrant preventive mastectomy."
These BRCA1 and 2 mutations are rare, and most experts agree only women with a very particular family history and risk profile should bother getting tested. Yet the study suggests women followed Jolie into medical screening they didn't need.
That's not to mention the cost to the health system: At about $3,000 per test, the researchers estimate this Jolie-inspired surge led to $14 million in health care spending in those two weeks alone.
And the "Jolie effect" seemed to persist long after the op-ed appeared. Average monthly test rates increased from 16 tests per 100,000 women between January and April 2013 to 21 tests per 100,000 women after the op-ed during May through December that year.
In sum, this looks like a case of celebrity-induced overtesting, the researchers wrote: "Celebrity announcements can reach a broad audience but may not effectively target the population that would benefit most from the test."
This is just one of many examples of where a celebrity says something about health and we follow like sheep. In 2000, Katie Couric's awareness campaign about colorectal screening led to an increase in colonoscopy use, and was dubbed the "Katie Couric effect." News of Kylie Minogue's announcement about a breast cancer diagnosis in 2005 led to an "unprecedented increase" in mammography bookings. After Charlie Sheen disclosed last year that he was HIV-positive, researchers sifted through Google search information and found that his announcement "corresponded with the greatest number of HIV-related Google searches ever recorded in the United States."
"The research — on the aggregate, at the population level — says it's clear: Celebrity culture, celebrity endorsements, have an impact," said Tim Caulfield, a researcher and author of the book Is Gwyneth Paltrow Wrong About Everything?. "Now we can debate whether that's good or bad."