Higher mortality in men from COVID19 infection-understanding the factors that drive the differences between the biological sexes

Abstract

The emergent global pandemic caused by the rapid spread of Severe Acute Respiratory syndrome-Coronavirus-2 (SARS-CoV-2) has led to increased mortality and negatively impacted day to day activities of humankind within a short period of time. As the data is rapidly emerging from earlier outbreak locations around the world, there are efforts to assimilate this with the knowledge from prior epidemics and find rapid solutions for this. One of the observations and a recurring theme is the disproportionate differences in the incidence of infection and the consequent mortality between males and females. We, therefore, analyzed retrospective datasets from the previous epidemics and the ongoing pandemic in order to address these differences in clinical outcomes. The data shows that even though the infection rates are similar, the odds ratio of male mortality remains high, indicating a divergence in the crosstalk between the three pathogenic human Coronavirus (hCoVs)-the SARS-CoV, MERS-CoV and the SARS-CoV-2 and immune effectors in the two sexes. One proximate cause is the sex-specific modulation of the X-linked genes that can influence susceptibility to infection. Future studies are needed to confirm these findings, which can form the basis for developing rational strategies for ending the current and preventing future pandemics.

Epidemiological profile of COVID-19 deaths in the public hospital in Rio de Janeiro, Brazil

“…13,20,21 Moreover, the random effects model yields an aggregate odds ratio (OR) of 1.84 for comparing the odds of death for males to females, maybe for possible sex differences in the immune response. 22 The reasons for the observed differences related to COVID-19 deaths are multifactorial. Another important factor is to consider is the stage of the epidemic in which the country finds itself.…”

Physiological implications of COVID-19 in reproduction: angiotensin-converting enzyme 2 a key player

“…Moreover, Channappanavar et al (2017) found that the removal of the testes did not affect disease outcomes in male mice, whereas ovariectomy or treating female mice with the oestrogen receptor antagonists ICI-182 and ICI-780 resulted increased mortality to SARS-CoV infection, signifying that oestrogen signalling protects female mice from lethal SARS-CoV infection. In light of the recent pandemic situation, the same research team has stated that this could also be the reason for the male susceptibility to COVID-19 (Iyer et al 2020).…”