Many Patients Unaware of Overdiagnosis Harms

May 28, 2015
Ryan Marotta, Assistant Editor

Patients remain largely uninformed about the dangers of unnecessary disease screening and overdiagnosis.

Patients remain largely uninformed about the dangers of unnecessary disease screening and overdiagnosis.

A new study published in PLOS One surveyed 500 Australians on their knowledge and views of overdiagnosis, which occurs when a patient is diagnosed with a disease that is unlikely to progress to cause harm, often when screened for diseases such as breast or prostate cancer.

Nearly 90% of those who had been screened for breast cancer said they were not informed about overdiagnosis risks, and more than 80% of men screened for prostate cancer reported the same.

Across all those surveyed, only 1 in 10 said they had been told about overdiagnosis, while 93% expressed a desire for information on both the benefits and risks of disease screening.

“Our survey results show we need to better inform the community about the harms as well as benefits of screening, including the important harm of overdiagnosis,” said study co-author Kirsten McCaffery, PhD, in a press release.

The study authors suggested a potential cause of overdiagnosis is expanded disease definitions that include patients with mild problems and those at very low risk of illness.

In an exclusive interview with Pharmacy Times, lead study author Ray Moynihan, PhD, noted the results of the Australian survey could likely be applied to American patients, despite clear differences between the 2 nations’ health care systems.

“As someone who has lived and worked in the US and studied health systems and overdiagnosis, I can see no reasons to think there would be very different results in the US,” Dr. Moynihan told Pharmacy Times, though he acknowledged a separate US survey would be needed to verify this hypothesis.

This is not the only recent study to evaluate the risks of overdiagnosis, as an inquiry in the United Kingdom estimated 1 in 5 cancers diagnosed through breast cancer screening would not harm the affected women. Additionally, an analysis published in Health Affairs estimated breast cancer screenings results in the potential overdiagnosis of more than 20,000 women a year in the United States, at a total cost of more than $1 billion.