Advocacy from independent experts reflected in new ob-gyn guideline

A group of independent doctors spoke out in 2019 against what they saw as a potentially harmful recommendation that was influenced by financial conflicts of interest. The guideline advocated expanding the use of blood thinners for most women who had a cesarean birth, despite a lack of evidence to support this rule, leading to more women being given these medications unnecessarily.

Now it appears that the independent doctors’ advocacy has helped to change that practice. In August 2020, the Society for Maternal-Fetal Medicine and American College of Gynecology released their recommendations for blood thinners in women undergoing c-section. The new guideline acknowledges the lack of evidence behind broad use of blood thinners for all c-section patients, and instead recommends treating just higher-risk c-section patients with these medications.

“The fact that 46 of us stood against this pharma-funded approach may have helped bring evidence to this guideline,” said Dr. Adam Urato, Chief of Maternal-Fetal Medicine at the MetroWest Medical Center in Framingham, Massachusetts, who led the effort by independent doctors to speak out.

Jeanne Lenzer, investigative journalist and one of the creators of the List of Independent Experts, sees this new guideline as an example of what independent doctors can do when they advocate for patients. “This could be the beginning of a movement in which doctors from the international List of Industry-Independent Health Experts can come together to challenge clinical practice guidelines – most of which are compromised by financial conflicts of interest,” said Lenzer.

Blood thinners for all?

In 2016, the National Partnership for Maternal Safety (NPMS) released a list of recommendations for reducing deaths from blood clots in pregnant and postpartum women in the journal Obstetrics & Gynecology, popularly known as the “Green Journal.” One of these recommendations was expanding the use of blood thinners to most women after a cesarean birth. Since nearly one third of births in the US are by c-section, that’s about 1.3 million women a year who would be put on blood thinners after giving birth. This broad expansion of blood thinners was concerning to doctors who noted that this practice “is not justified by the available data and has the very real potential of doing more harm than good.”

Urato was also very concerned that the NPMS guidelines may have been influenced by industry connections. NPMS has significant has financial ties to industry companies, including three that manufacture or sell blood thinners. However, the 2016 recommendations did not include any of these conflict of interest disclosures from the NPMS. Urato reached out to doctors from the List of Independent Experts, and soon had a coalition of nearly fifty professionals. They wrote a letter to Obstetrics and Gynecology, which was published in November 2019, describing their concern both about the conflicts of interest and lack of disclosure of these conflicts in the journal. The letter also got the attention of major media outlets like the Wall Street Journal.

A new evidence-based guideline

In August 2020, the Society for Maternal-Fetal Medicine and American College of Gynecology released new recommendations on preventive thrombolytic treatment for women undergoing c-section. The guideline authors write that all women having a c-section should be given compression cuffs to stimulate blood flow, and those with a history of blood clots or family history of blood clots should receive blood thinners. But for women at low risk of blood clots, there is not enough evidence to support that they receive blood thinners, they write, reversing the recommendation from the NPMS.

The SMFM/ACOG document outlines the potential benefits and harms of giving all women blood thinners. The authors note that even among women at high risk of blood clots after surgery, 640 would need to take blood thinners to prevent one episode of venous thromboembolism (a dangerous blood clot that starts in the leg). At the same time, blood thinners can lead to the c-section wound separating and bleeding after the operation; one in 200 women to take blood thinners after c-section may be harmed.

While using compression cuffs to get the blood flowing is an inexpensive and safe intervention, the decision to use drugs to get the blood flowing is not as straightforward, and depends on the patient’s level of risk from blood clots. The SMFM/ACOG recommends that patients with a personal history of deep venous thrombosis or pulmonary embolism or family history of blood clots receive blood thinners, although they acknowledge that there is still not a high quality of evidence to support this recommendation.

Challenging industry influence in guidelines

Obstetrics is far from the only medical field in which industry conflicts may influence clinical practice guidelines. Evaluations of guidelines for gastroenterology, dermatology, oncology, and more find that the majority of guideline authors receive industry payments, and many receive payments in excess of $10,000.

“This dynamic is harmful to patients and the public because it often results in recommendations that put the profits of the drug companies above the health of patients and the public. There is a desperate need for clinical guidelines that are not influenced by corporate cash,” said Urato.

When it comes to clinical guidelines for cholesterol and heart health, financial conflicts of interest not only affect panelists’ interpretation of data, they “can also blind panel members to the fact that neither they nor the peer reviewers have been granted access to the underlying clinical trial data,” said John Abramson MD, MSc, Lecturer in the Department of Health Care Policy at Harvard Medical School. “Without seeing the underlying trial data, guideline panel members are not able to ensure that the analyses they are integrating into their guidelines are accurate and complete.”

“The IOM/NAM recommends that no members of guideline panels have conflicts of interest (and certainly not a majority), and no chairs or vice chairs have conflicts of interest. But both of these recommendations are routinely violated, and this is highly likely to bias the guidelines in favor of the manufacturers,” said Abramson. “Independent physicians could bring attention to these violations.”