Association between pharmaceutical modulation of estrogen and death from COVID-19 in Swedish postmenopausal women: a cohort study 

Sund M, Fonseca-Rodríguez O, Josefsson A, et al Association between drug-mediated regulation of estrogen and death from COVID-19 in Swedish postmenopausal women: a cohort study BMJ Open 2022; 12: e053032. doi: 10.1136/ bmjopen-2021-053032

Commentary

This study was examining whether increasing estrogen levels in postmenopausal women reduces the risk of mortality after COVID-19 morbidity.

The study was based on the Swedish Public Health Agency registry and was　constructed through a nationwide registry-based study.

The sample consisted of postmenopausal women aged 50-80 years who were identified as COVID-19. They were tested in subjects who had previously been diagnosed with breast cancer and were receiving endocrine therapy or hormone replacement therapy, and in a control group who did not meet these criteria.

The analysis was adjusted for potential confounders such as age, annual disposable income, highest level of education, and weighted Charlson Comorbidity Index (wCCI).

As an outcome, they were mainly examining death after COVID-19.

From a cohort of 49,853 women diagnosed with COVID-19 between February 4 and September 14, 2020 in Sweden, 16,693 were sampled.

Fourteen thousand six hundred and eighty-five met the study criteria, and 11,923 were included in the control group. In group 2, with an OR of 0.47 (0.34-0.63), only the adjusted OR for death remained significant, finding that the absolute risk of death was 4.6% in the control group, compared to 10.1% and 2.1% in the reduced and increased estrogen groups, respectively. And the risk of death after infection was significantly reduced, indicating that even after adjustment, estrogen supplementation in postmenopausal women is associated with a lower risk of death from COVID-19. However, these findings also seem to be beneficial at this stage, although the researchers said that randomized intervention trials are needed.