Do industry ties influence changing disease definitions?

There potentially could be ulterior motives behind the changing of disease definitions, a study published in the August issue of PLOS Medicine found. When diagnostic criteria were expanded for some conditions, most members of the decision-making panels had financial ties to the pharmaceutical industry and none of the panels reported thoroughly assessing the potential consequences of the broadened disease definitions.

These findings, according to the study, could be contributing to the overdiagnosis of several conditions, including hypertension.

The study authors, led by Raymond N. Moynihan of Bond University in Robina, Australia, analyzed panel publications from the U.S. on diagnostic criteria between 2000 and 2013. They determined how the new proposals affected disease definition, the reasons behind the changes, whether the panels addressed potential harms and any industry ties.

They looked at 16 publications on 14 conditions common in the U.S., including MI and hypertension. Of those 14, 10 supported widening definitions and one suggested narrowing for reasons including standardizing criteria and new studies on risks among disease-free people. None of the publications offered a comprehensive assessment of how the new definitions could harm patients, although six briefly mentioned it.

The researchers also found numerous potential conflicts of interest within most of the panels.

“Among 14 panels with disclosure sections, the average proportion of members with industry ties was 75 percent,” they wrote. “For members with ties, the median number of pharmaceutical or device companies to which they had declared ties to was seven.”

Panel members with ties often served as consultants, advisers or speakers and may also have received support for their research.

“Companies with financial relationships with the greatest proportion of panel members were marketing or developing drugs for the same conditions about which those members were making critical judgments,” they added.

The study did not uncover a causal relationship between the two variables, but it suggested there could be unexplored dangers to patients that may warrant additional research. The data, they argued, may also point to the need for alternative strategies for reviewing disease definitions that are “free of financial conflicts of interest and informed by rigorous analysis of benefits and harms.”