Fewer smokers than expected get the disease - but why?
Fewer smokers than expected are being hospitalised for Covid-19. Researchers suspect that nicotine may influence the disease. But it could just as well be a class issue. So says Louise Adermark, a nicotine researcher at the University of Gothenburg.
Could it be that nicotine reduces the rate of smoking among those needing treatment for Covid-19? This question is now being asked by researchers around the world.
According to Konstantinos Farsalinos, cardiologist and specialist in cardiovascular diseasesbut also known for his research on e-cigarettes, Covid-19 could be a disease made worse by a strong reaction from the immune system. A so-called cyclosporine storm. And that's where nicotine comes in. Nicotine has known properties that inhibit such a reaction.
"The disease becomes more difficult to control when the immune system, at a late stage, attacks its own cells. Nicotine could work to control that process," Farsalinos and his colleagues write in the the online version of the scientific journal ScienceDirect.
Mr Farsalinos and his research colleagues already observed in early March that the proportion of smokers requiring advanced care for COVID-19 does not correspond to the proportion of the population who are de facto daily smokers. And as Vejpkollen previously reported, French researchers have observed the same pattern among COVID-19 patients in France. Although many smokers are severely affected by COVID-19, statistically, smokers are underrepresented among the more severe cases. The French researchers now want to test nicotine patches in the treatment of COVID-19.
Nicotine affects diseases
But there is considerable uncertainty about the role of nicotine. Nicotine certainly has properties that affect the course of various diseases. But there is currently no developed treatment with nicotine. At least not directly. Nicotine researcher Louise Adermark, Department of Neuroscience and Physiology at the University of Gothenburg, notes that there is still some knowledge about the effects of nicotine.
"To my knowledge, there is no treatment based on nicotine, although there are treatments that affect acetylcholine - which in turn activates nicotine receptors. This is important in, for example, Alzheimer's disease and some other motor disorders," she told Vejpkollen.
However, Louise Adermark believes that there may be some benefits of nicotinealthough the current state of knowledge is unclear.
'Several cells of the immune system can be activated by nicotine. When it comes to medicines, it is primarily CERTAIN nicotine receptors that we want to activate. For example, many studies show that nicotine receptors have anti-inflammatory and neuroprotective effects. Others may have a more negative effect. For future treatments, it is important to have drugs designed to act on a specific receptor subtype." says Louise Adermark.
Could be a class issue
The under-representation of smokers among COVID-19 patients can also be explained in other ways, she says. 'And it doesn't have to do with nicotine. It could just as well be due to economic factors. A class issue, in other words.
"One should be aware that those who are infected, and who are smokers, often have very serious symptoms. To be blunt, there is also a socio-economic aspect here. Population groups that have a high proportion of smokers may also, to a lesser extent, have an economy that allows them, for example, to go to Italy on a skiing holiday. This in turn could lead to fewer infections in that group globally," says Louise Adermark.
At the same time, more studies could be interesting, she says. Especially in Sweden, where nicotine is used by many people who do not smoke cigarettes.
"It would be interesting to see if similar figures apply to our Swedish snus users" she tells Vejpkollen.
