Hormone replacement therapy associated with reduction in mortality from COVID-19

A new paper in Family Practice, published by Oxford University Press, indicates that receiving hormone replacement therapy within six months of a recorded diagnosis of COVID-19 was associated with a reduction in mortality from the disease.

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread. Men and women are equally susceptible to the infection. Men tend to have more severe infections, however, and have higher rates of hospitalization and mortality. A recent review of sex differences in COVID-19, using data from 38 countries, found mortality in men was 1.7 times higher than in women. Younger women or those with higher estrogen levels are less likely to experience COVID-19 complications.

Earlier studies have also shown that women have faster and greater immune responses to viral infections. Researchers have observed similar data in previous pandemics, including the SARS-CoV (Severe Acute Respiratory Syndrome Corona Virus) and MERS-CoV (Middle East Respiratory Syndrome Corona Virus) outbreaks.

The reason for these sex differences is uncertain. Limited recent observational data suggest that estrogen may reduce the severity of COVID-19 disease. This study investigated the association between hormone replacement therapy or combined oral contraception use, and the likelihood of death in women with COVID-19. Researchers investigated combined oral contraception, which contains estrogen, because some Recent observational data suggests that women taking oral contraceptives have a lower risk of acquiring COVID-19.

Investigators used a retrospective cohort with medical records from the Oxford-Royal College of General Practitioners Research and Surveillance Centre primary care database. They identified a group of 1,863,478 women over 18 from 465 general practices in England. There were 5451 COVID-19 cases within the cohort. Hormone replacement therapy was associated with a 22% reduction in all-cause mortality in COVID-19.

This suggests that estrogen may well contribute a protective effect against COVID-19 severity. This may explain why fewer women compared to men have been hospitalized, admitted to intensive care, or died due to COVID-19 during the pandemic.

This study supports the theory that estrogen may offer some protection against severe COVID-19. We hope that this study can provide reassurance to patients and clinicians that there is no indication to stop hormone replacement therapy because of the pandemic."

Christopher Wilcox, Author