Vaccine, pills and thrombosis: the benefit / risk ratio is also political

On March 15, the statement of the President of the Republic produced a thunderous effect. While the vaccination campaign in France struggled to reach its goals, Emmanuel Macron decided to suspend the use of AstraZeneca, the last approved vaccine.

Then France joined the decisions of some of its European colleagues. After Denmark, Norway or Austria, Germany decided to suspend this vaccine: The Paul Ehrlich Institute, the federal agency for the regulation of German medicines and vaccines, did report that a serious brain form and a very rare venous thrombosis had been declared. 7 people under the age of 50 after injection.

A few days later, on March 18, the Pharmacovigilance Risk Assessment Committee of the European Medicines Agency (EMA) published its conclusion: “The proven efficacy of the vaccine in preventing hospitalization and death of patients with Covid-19 far outweighs the very low risk. development of thrombosis of the venous sinus of the brain or disseminated intravascular coagulation ”.

The next day, the French government decided to resume vaccination with AstraZeneca, limiting the use of the vaccine to people over 55. But the withdrawal has enabled patient associations such as the AVEP (Association for Victims of Pulmonary Thromboembolism and Stroke) or her German counterpart Riziko Pille to question what they denounce as political asymmetries about thrombosis risk.

Clearly, how is it to be explained that the risk, estimated at 1 in 2,500 each year, for women taking 3rd or 4th generation birth control pills is so little recognized and recognized? And this, when at the same time the risk, estimated at 6 cases per million vaccinated people, is the subject of similar scrutiny …

Multiple consequences and causes

Venous thrombosis is a very diverse and relatively common medical category. The spectrum of their clinical consequences is very wide: from superficial phlebitis and minor side effects to death from pulmonary embolism, including post-thrombotic syndromes with severe disability.

These accidents can occur after surgery, prolonged immobilization, or even during pregnancy. But thrombosis is also associated with taking various medications, in particular birth control pills. But nine years ago, an increased risk of thrombosis was associated with taking three pills.e and 4e the generation was mixed during the media coverage of the young woman’s case.

In 2006, at the age of 18, Marion Larat did indeed become a victim of cerebrovascular disorder (CVA), the serious consequences of which she retained. When she discovers a few years later that this stroke was likely caused by her contraception with 3 pille generation, the young woman decides to prosecute the manufacturer, Bayer, as well as the National Agency for the Safety of Medicines (ANSM), which authorized its marketing.

This complaint will open up a period of questions about the side effects of the pill in which other members like AVEP will get involved and trigger what some call a “pill crisis.”

Emergency vaccine

The controversy surrounding the risk of thrombosis associated with either the pill or the AstraZeneca vaccine arises at different stages in the distribution of these products.

In the case of the vaccine, due to a serious social hazard, a conditional marketing authorization was used. This faster and easier process has fewer requirements. But use is dependent on an enhanced pharmacovigilance system to indicate the benefit / risk assessment.

Thus, cases of thrombosis after AstraZeneca injection, although very rare, have been identified by physicians in relation to their specific clinical presentation. Not only are thrombosis located in unusual anatomical areas, but their association with a lack of platelets makes treatment much more difficult.

In practice, the AEM decision on March 18 led to the inclusion of a new item in the vaccine information booklet published on March 19, 2021. The latter points to the existence, in very rare cases, of a link between vaccines. and thrombosis, mainly in women under the age of 55. He encourages health care providers to be attentive to the signs and symptoms of thromboembolism, and to inform vaccinated people, recommending that they consult at the first warning signs.

Pills, ancient marketing

The situation is different with combined hormonal pills. When the pill of the crisis 3e and 4e generations broke out in 2012, some of these contraceptives have received their MA for over twenty years (those dates are listed for each product in the Vidal dictionary).

These MAs were provided by health authorities based on an overall assessment of the balance between benefits, risks and side effects that were considered beneficial. But, as with any drug, the responsibility for the prescription rests with doctors: they must conduct a second assessment of the balance between risks and benefits, individually and tailored to each one. Therefore, the prescription is not recommended for women who smoke, have diabetes, have a family history of thrombosis, liver problems, or are older than a certain age.

This vision of balancing the benefits and risks of estrogen-progestogen pills has been promoted since the late 1960s and early 1970s. At the time, abortion was illegal, and doctors and activists in the French family planning movement offered medical contraceptives. As a response to what they see as a social calamity, a health disaster and a real public health problem in a country where refusal to have intercourse is the main method of contraception.

The argument for unsafe pregnancy and abortion

In this context, the risks associated with estrogen-progestogens, demonstrated in the late 1960s by extensive epidemiological studies involving several tens of thousands of women, are compared with the risks of unwanted pregnancy. But they are also being investigated for the risk of abortion, especially when the latter are performed in poor sanitary conditions.

It is also indicated that there is a high risk of thromboembolism during pregnancy or abortion. Therefore, the risk of thrombosis associated with pill use is considered low given the benefits of this method of contraception, both in terms of fertility control and in terms of reducing direct health risks for women. control allows.

In this case, the risk becomes an undesirable phenomenon indicated in the leaflets of these medicines. And the doctors will have to identify at a preliminary medical examination women of the “risk group”, to exclude them from the prescription. For connoisseurs of that time, the pill is safe if it was prescribed within the limits of contraindications.

Risks in perspective

This estimate of the “benefit / risk balance” of estrogen-progestogen pills was regularly challenged during the 1960s and early 1980s. But in France, systematically, when the risks associated with pills are mentioned, experts and, in particular, some gynecologists and endocrinologists are mobilized in the media to put them in perspective, while confirming the superiority of pills as a means of contraception.

This concept, which can be described as “birth control pills,” will be widespread among women, but also among many prescribers. The latter has a strong influence on the determination of the individual benefit / risk balance when prescribing tablets: the thrombotic risk is not sufficiently taken into account.

The 2012 crisis, however, will provide new media with information on the risks of contraceptive pills, and at the same time will be a moment of crystallization of the claims made by the associations. They regret then and still relate to the overly systematic practice of prescribing drugs, not striving for individual characteristics: for most women, due to the lack of sufficient information, the risk of thrombosis is completely invisible.

This crisis also offers an opportunity to question the sharing of contraceptive risks between partners: pill-based contraceptive policies are accompanied by a very gender-based vision of fertility management, where the responsibility, mental health burden and risks rest with women alone. …

Finally, the crisis rekindles the debate about the dominance of health care providers in contraceptive selection and fertility management. Pill-based education and practice dictates the contraceptive choices actually offered to women and men, leaving little room for their individual preferences or their lifestyle.

The calculation depends on the social context

The history of the contraceptive pill shows this: the balance of health benefits / risks of mass-prescribed health products for populations of healthy people and whose benefits combine individual and collective aspects of public health is not a matter of simple mathematical calculation.

Of course, this can only be determined on the basis of knowledge of the desired or undesirable effects of the product. But it also depends on the social context in which the product is used, on the functions it is intended to perform (fertility control, immune defense against viruses) and therefore on the way these functions are defined. …

Note, however, that after being evaluated within administrative standards (MA, decision on reimbursement through health insurance, etc.), and then applied in daily practice in mainstream medical practice, the benefit / risk balance loses its meaning. measurement of social construction. It then turns into a fixed value indicator that will be strictly objectively objectified from a scientific point of view. And in mediatized expert discourse, it simply becomes “positive” or “negative”.

It should also be remembered that the social acceptability of the risks associated with drugs and the assessment of their benefits are not intangible data – like the media coverage of claims made by associations of victims of thrombosis associated with pills.

Finally, in addition to medical and public health aspects, it should be noted that the benefit / risk balance also reflects political trade-offs between different stakeholder groups with diverging interests. These arbitrations make the risks associated with a product or medical device more or less transparent, depending on the geographic or historical context in which the power relationships between these participants are expressed.

Back to top button