Knowing how SARS-CoV-2, the virus that causes COVID-19, affects different groups of people is one way to help healthcare workers streamline treatment. Studies done in several countries with large patient populations have found that men with COVID-19 have worse outcomes than women.

Underlying conditions, or comorbidities in men; immune system differences between men and women; and hormonal factors are among the factors that have been associated with COVID outcomes, though no definitive risk factors have emerged.

Getting a clearer understanding of how risk factors for COVID-19 differ between men and women should not only improve clinical risk assessment, it will likely also add to our understanding of how the SARS-CoV-2 virus affects men as opposed to women. That's why a team of researchers from the Icahn School of Medicine at Mount Sinai undertook a study designed to highlight the differences between men and women in the clinical course of COVID-19.

Men were less likely than women to have underlying health conditions such as obesity or hypertension, but they were more likely to die from COVID-19 or have serious outcomes.

The process of figuring out why certain patient populations have poorer outcomes begins with very careful monitoring of SARS-CoV-2’s effects on various populations. As researcher Kuan-lin Huang told TheDoctor, “Different sexes or different age groups may have a different response to different vaccines, and different vaccines may offer different levels of protection.”

Timing is Important
The study compared COVID-19 outcomes in nearly 5,000 patients hospitalized with COVID-19 between March and August 2020 with those of a validation group of almost 1,700 patients hospitalized between August 2020 and January 2021.

Among patients hospitalized with COVID-19 early in the pandemic, men were less likely than women to have underlying health conditions such as obesity or hypertension. However, men were more likely to die or have serious outcomes such as admission to intensive care and intubation, when factors such as age or other comorbidities were taken into account.

Although men hospitalized early in the pandemic were more likely than women to have low oxygen levels, or hypoxia, women with hypoxia were more likely to die from COVID-19 early on. And women who were obese were at increased of intubation or admission to intensive care.

What was surprising about the findings of the current study were the gender-specific effects of comorbidties on COVID-19 outcomes. “It was interesting to us that even though men were doing worse in general, women were more likely to be affected by hypoxia in the earlier phases of the pandemic. And women were more likely to be affected by obesity early on,” said Huang, an assistant professor of genetics and genomics at the Icahn School of Medicine.

Data on the progression of the disease among distinct populations need to be made widely available, he believes, in order to help doctors better care for patients with COVID-19.

Men still had worse outcomes when all other factors were taken into consideration, but, Huang explained, because the overall mortality rate among patients hospitalized with COVID-19 improved later in the pandemic and care for patients with COVID-19 also improved, gender-specific COVID-19 outcomes remain unclear.

The study is published in Nature Communications Medicine.