To those who would like to use it to protect themselves against Covid-19, a reminder of the disastrous effects of nicotine

While the Covid-19 pandemic has taken hold of most countries in the world, the international scientific community is mobilizing to find ways to contain it. At the end of April, in France, researchers mainly from CNRS, Inserm, APHP and Institut Pasteur began to focus on the therapeutic consequences of nicotinic receptor modulating agents. In other words, they suggest that nicotine might protect against the novel coronavirus.

If it were to be verified, this hypothesis – which is the subject of several studies – should not encourage anyone to start smoking, nor to increase their consumption of cigarettes. Indeed, a study published in the May 2020 issue of the journal Hypertension reveals the implications of chronic nicotine exposure in the development of cardiovascular and pulmonary diseases. According to scientists, it could lead to pulmonary hypertension.

Harmful effects from the first week of exposure

To carry out their work, the researchers, from the Louisiana State University Health Sciences Center New Orleansused a new model of nicotine inhalation in mice, which closely mimics human smokers, as well as e-cigarette users.

For eight weeks, they examined the effects of chronic nicotine inhalation on the development of cardiovascular and pulmonary diseases. They were particularly interested in blood pressure and cardiac remodeling — the most common cause of heart failure after a heart attack. Result: from the first week of exposure, nicotine inhalation increased systolic blood pressure — measured during the relaxation phase of the heart — and diastolic — corresponding to contraction of the heart — mouses.

Rise in right ventricular systolic pressure

“The increase was temporary, but was long enough to pose potential health risks to people with pre-existing cardiopulmonary conditions”says Eric Lazartigues, professor of pharmacology at Louisiana State University Health Sciences Center New Orleans, in a press release published on the establishment’s website.

In addition to pulmonary hypertension induced by chronic nicotine inhalation, the researchers found that nicotine led to “muscularization” of previously non-muscular pulmonary arterioles — small branches of arteries leading to capillaries. This phenomenon is consistent with an increase in right ventricular systolic pressure and pulmonary vascular resistance.

Right ventricular failure, a leading cause of death in pulmonary hypertension

As a reminder, right ventricular failure is one of the main causes of death in pulmonary hypertension. However, the researchers found that an eight-week exposure to nicotine resulted in significantly higher right ventricular systolic pressure, as well as thickening of the walls and right ventricular hypertrophy. Enough to discourage those who relied on nicotine to protect themselves against Covid-19.