The effects of SARS-CoV-2 infection on the cardiovascular system in men and women need to be further investigated, as there are various indications that there are important sex differences in the effects of the resulting disease, COVID-19. This is what Georgios Kararigas, Professor of Physiology at the School of Medicine of the University of Iceland, says in an Editorial published in Physiological Reviews, a prestigious scientific journal in the field of Physiology and Medicine.
Kararigas has recently joined the University of Iceland, but his research work has been focusing on sex differences in physiology and diseases related to the cardiovascular system. In the article in Physiological Reviews, Kararigas summarizes various studies investigating the effects that SARS-CoV-2 is known to have on the body, with special emphasis on the cardiovascular system, but as is well known, the effects of COVID-19 on patients have been shown to vary in severity, ranging from mild symptoms to death.
Kararigas points out that one of the factors that seems to affect symptoms and mortality is biological sex. Men appear to be at greater risk of developing severe symptoms or dying from COVID-19 than women, but at the same time certain sex-specific conditions seem to make women more susceptible to the disease. He points out that there are indications that pregnant women are more likely to become seriously ill from the virus than is generally the case. Kararigas further points out that people with underlying conditions, such as cardiovascular diseases, suffer from more severe symptoms and are more likely to die from COVID-19.
In the article, Kararigas also says that much is still unclear about the effects of COVD-19 on the cardiovascular system and how these may differ between the sexes. It has been found that the virus causes damage to the cardiovascular system in some parts of patients, which may eventually lead to cardiac dysfunction and arrhythmia. Interestingly, studies conducted early in the US epidemic have shown that the majority of those who suffer from such symptoms are men. However, it is currently not easy to make clear conclusions, because the consequences of the disease are very different among people. Some patients of both sexes struggle with chest pain many months after the infection, which raises the question of whether there is a further effect of the disease on the cardiovascular system in the long term.
In the article, Kararigas highlights various physiological factors that may influence the response to the disease in a sex-dependent manner. Inflammatory responses are known to differ between men and women, including those with cardiovascular diseases. One of the hallmarks of COVID-19 is an exaggerated inflammatory response of the body to the infection and it is possible that an inflammatory response to the disease leads to a more serious effect on the cardiovascular system in men than in women.
Kararigas points out, however, that it is not possible to draw clear conclusions in this regard, as there is a lack of data on the various effects of this harmful disease between the sexes. This needs to be improved in order to gain a better understanding of the underlying factors that influence the development of the disease. Also, sex-based biomarkers that can predict an increased risk of severe symptoms, hospitalization and even death in COVID-19 patients may be of great importance (biomarkers may be molecules in the blood or elsewhere in the body that indicate a person's biological condition). By finding such biomarkers, it is possible to identify those patients who are at most risk from the disease and thus adapt treatments in a sex-dependent manner, thereby reducing any long-term effects of the disease in an individualized approach. Therefore, there is a need for comprehensive long-term research, ensuring that sufficient numbers of both men and women are studied.
The Editorial is available on the Physiological Reviews website.