Why are men more at risk of suffering from severe COVID-19? New study attempts to find out

The researchers included 3,086 COVID-19 patients admitted to the hospital on or before 13 April 2020 until 2 June, and already had a majority of about 59.6% male patients. The men admitted were younger on average and less likely to have comorbidities such as hypertension, diabetes and obesity, in comparison with women.

Read more: COVID-19 fatality rate in patients with diabetes

The study, however, found that even though the laboratory markers for women were lower than the male patients and unadjusted mortality was also similar between the two sexes, more men on average were in need of intensive care than women. 

They found that the male sex was itself an independent risk factor for mortality after adjusting for other key factors such as demographics, pre-existing health conditions as well as baseline hypoxia. It must be noted that previous studies have also found people from poorer socio-economic backgrounds and certain ethnicities to be more at risk of contracting the severe symptoms of COVID-19 as well.

Read more: Over 17 million patients analysed to determine risk factors for COVID-19 deaths

The male patients who were admitted were of the average age of about 64 years, while for women it was about 74 years, a full 10-year difference between the hospitalised patients. There was a higher prevalence of male patients who were smokers as well, although women had a higher rate of underlying conditions such as hypertension, diabetes, obesity and COPD or asthma.

Read more: COVID-19 and COPD

The differences in the clinical markers suggested that male patients were 20% more likely to suffer from death in comparison with female patients.

However, when calculating mortality risk after taking the above-mentioned comorbidities into consideration, women with pre-existing conditions were at a higher risk of suffering from mortality from COVID-19 than their male counterparts.

The findings even suggested that men with conditions such as heart disease or obesity did not have any effect on mortality due to COVID-19, although the same conditions elevated the risk in women, making them 75% to 80% more likely to die from the infection.

Read more: Common causes of death in COVID-19

As mentioned above, the comparatively lower laboratory markers among women than men that included white blood cells that are key in fighting off inflammation in the body indicate the higher likelihood of men suffering from poorer outcomes in the case of COVID-19. The higher number of these markers, as well as cytokines such as IL-6 and IL-8 also signal a higher likelihood of death.

Read more: What is a cytokine storm

Even though the findings of the study suggest men are at a higher risk of death and suffering from severe complications of COVID-19, certain factors such as underlying obesity or heart disease put women at a higher risk of death from the viral infection. However, the chances of suffering from severe complications or mortality are anyway higher among those with comorbidities.

Some of the findings of the study performed at Icahn are similar to what previous research that was done elsewhere around the world has shown. A study published in Frontiers in Public Health earlier suggested that they found similar evidence of men suffering from severe outcomes even in the case of earlier disease outbreaks such as SARS and MERS. The World Health Organization (WHO) reported that about 63% of the deaths in Europe were that of men.

The study done in China, where the disease is said to have originated, looked at case fatality records and reported that twice as many men had died of the infection as women. Another study from Wuhan had also suggested that out of the laboratory markers checked, male patients had higher figures in 11 of those markers, while some other parameters increased significantly as the disease progressed until the patients died.

Italy, which was one of the first countries to be badly hit by the pandemic, reported about 80% of their patients who were admitted to intensive care were men. Another critical factor that has been thought to be leading to higher infections in men has been the higher expression of cell receptors such as ACE2 receptors—the SARS-CoV-2 virus attaches itself to this receptor to infect an individual.

The new research, however, looked at other clinical and molecular factors which are specific to men and women to be able to arrive at their findings. The findings of the study could be critical in identifying the patterns of the disease in men and women, and why it affects them differently, which could ultimately lead to more focused diagnosis and treatment for both sexes.