COVID-19 usually presents as a respiratory illness, but cardiovascular complications such as irregular heartbeat (arrhythmia), lack of blood flow to the brain (stroke), and heart failure are also reported in some patients. Men tend to have worse COVID-19 outcomes than women. Since pre-existing cardiovascular disease is a known risk factor for severe COVID-19 and has a higher incidence in men, it has been proposed as a possible explanation for these sex differences.
Dr Carinna Hockham from the George Institute for Global Health, UK, in association with Imperial College London, who led the research, said:
“Our research aimed to understand whether sex differences in the severity of COVID-19, including the risk of death, and in cardiovascular complications, were explained by the higher prevalence of pre-existing cardiovascular diseases in men compared to women . ”
The study analyzed 11,167 patients who were hospitalized with COVID-19 between May 2020 and May 2021 in 13 countries. The team found that 13 out of 100 women and 17 out of 100 men developed some type of cardiovascular complication during their hospital stay, representing a 30% lower risk in women.
Arrhythmia was the most common cardiovascular complication, observed in 5 out of 100 women and 8 out of 100 men . Other complications, such as cardiac ischemia and pulmonary embolism, were less frequent.
The researchers found that sex differences in rates of cardiovascular complications were evident regardless of whether they had preexisting cardiovascular disease. They argued that the results not only have implications for the general understanding of sex differences in health and disease, but also demonstrate the critical importance of considering sex and gender differences in all aspects of human health.
Hockham said: “Our finding that the so-called ’male disadvantage’ in COVID-19 severity cannot be explained solely by pre-existing cardiovascular disease burden indicates that other factors are contributing to disease severity. "More research is needed to better understand why men are at higher risk for severe COVID-19, including examining whether viral mechanisms affect women and men differently."
What is already known about the topic
- Women with Covid-19 disease have a lower risk of respiratory failure, hospitalization or death than men.
- It is unclear whether these sex differences in Covid-19 disease extend to cardiovascular complications or to what extent the differences are explained by the lower prevalence of pre-existing cardiovascular diseases in women.
What does this study contribute?
- Female participants admitted to hospital for Covid-19 had a lower risk of arrhythmia, cardiac ischemia, pulmonary embolism or death than male participants while in hospital.
- These sex differences persisted in patients with preexisting cardiovascular disease and could not be explained by the lower prevalence of cardiovascular disease in female participants.
- No differences were seen between the sexes for the risk of heart failure or stroke
How it can affect clinical practice
- More research is needed to better understand the male disadvantage in Covid-19, specifically whether the pathophysiological mechanisms of Covid-19 itself affect women and men differently.
Conclusions In patients admitted to hospital for Covid-19, female participants were less likely than male participants to have a cardiovascular complication. The differences between sexes cannot be attributed to the lower prevalence of pre-existing cardiovascular disease in women. The reasons for this advantage in women require more research. |
