February 14, 2022

expert reaction to study looking at oestrogen levels and COVID-19 mortality

An observational study published in BMJ Open looks at pharmaceutical modulation of oestrogen in postmenopausal women in Sweden, and death due to COVID-19.

Prof Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said:

“This is an observational study comparing three groups of women, based on whether they used hormonal therapy to boost oestrogen levels or who had, as a result of treatment for breast cancer, had reduced oestrogen levels or neither. The findings are apparently dramatic. However, it must be remembered that there is a long history of observational studies, especially in relation to hormone therapy, making dramatic claims of benefits that have not been confirmed in randomised trials.

“It is quite likely that this study follows in such a line, and at the very least, great caution should be exercised in thinking that menopausal hormone therapy will have substantial, or even any, benefits in dealing with Covid-19.

“There are many reasons for finding that studies of this type can have very serious biases in them. There is little doubt that women have lower risks than men, at any given age, of coronary heart disease mortality, but this is independent of whether they take hormonal therapy or not. Very noticeable different mortality due to Covid-19 between men and women is seen at ages beyond 70 and this is very unlikely to have any relation to menopausal hormone therapy. Such sex differences are noted in the paper, and for example is seen with venous thromboembolism (VTE), but VTE is very well known to be increased (not decreased) by menopausal hormone therapy (MHT).

“There are short-term benefits of MHT but women should not, based on this or other observational studies, be advised to take MHT for a supposed benefit on death from Covid-19.”

‘Association between pharmaceutical modulation of oestrogen in postmenopausal women in Sweden and death due to COVID-19: a cohort study’ by Sund M, et al. was published in BMJ Open on 23:30 UK time on Monday 14^th February 2022.

DOI: 10.1136/ bmjopen-2021-053032

All our previous output on this subject can be seen at this weblink:

www.sciencemediacentre.org/tag/covid-19

Declared interests

Prof Stephen Evans: “No conflicts of interest.  I am funded (one day per week) by LSHTM.  They get funding from various companies, including Astra Zeneca and GSK but I am not funded by them, I have no involvement in obtaining funding from them and I am not an investigator on any grants obtained from them.  I am the statistician to the ‘meta-Data Safety and Monitoring Board’ for CEPI.  I am paid for my attendance at those meetings and will be paid expenses for travel if that occurs.  I am a participant in the Oxford/Astra Zeneca trial, and on 13th January 2021 learnt I had received the active vaccine.”