Global Coagulation Assays in Transgender Women on Oral and Transdermal Estradiol Therapy

Hui Yin Lim; Shalem Y Leemaqz; Niloufar Torkamani; Mathis Grossmann; Jeffrey D Zajac; Harshal Nandurkar; Prahlad Ho; Ada S Cheung

doi:10.1210/clinem/dgaa262

Global Coagulation Assays in Transgender Women on Oral and Transdermal Estradiol Therapy

J Clin Endocrinol Metab. 2020 Jul 1;105(7):dgaa262. doi: 10.1210/clinem/dgaa262.

Authors

Hui Yin Lim^{1

2

3

4}, Shalem Y Leemaqz⁵, Niloufar Torkamani^{4

6}, Mathis Grossmann^{4

6}, Jeffrey D Zajac^{4

6}, Harshal Nandurkar³, Prahlad Ho^{1

2

3

4}, Ada S Cheung^{4

6}

Affiliations

¹ Department of Haematology, Northern Hospital, Epping, Victoria, Australia.
² Northern Pathology Victoria, Northern Health, Epping, Victoria, Australia.
³ Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia.
⁴ Department of Medicine (Austin Health), The University of Melbourne, Heidelberg, Victoria, Australia.
⁵ Robinson Research Institute, Adelaide Medical School, The University of Adelaide, Adelaide, Australia.
⁶ Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia.

PMID: 32413907
DOI: 10.1210/clinem/dgaa262

Abstract

Context: The thrombotic effects of estradiol therapy in transgender women are unclear. Global coagulation assays (GCA) may be better measures of hemostatic function compared with standard coagulation tests.

Objective: To assess the GCA profiles of transgender women in comparison to cisgender controls and to compare how GCA differ between routes of estradiol therapy in transgender women.

Design: Cross-sectional case-control study.

Setting: General community.

Participants: Transgender women, cisgender male and cisgender female controls.

Main outcome measures: Citrated blood samples were analyzed for (i) whole blood thromboelastography (TEG®5000), (ii) platelet-poor plasma thrombin generation (calibrated automated thrombogram); and (iii) platelet-poor plasma fibrin generation (overall hemostatic potential assay). Mean difference (95% confidence intervals) between groups are presented.

Results: Twenty-six transgender women (16 oral estradiol, 10 transdermal estradiol) were compared with 98 cisgender women and 55 cisgender men. There were no differences in serum estradiol concentration (P = 0.929) and duration of therapy (P = 0.496) between formulations. Transgender women demonstrated hypercoagulable parameters on both thromboelastography (maximum amplitude + 6.94 mm (3.55, 10.33); P < 0.001) and thrombin generation (endogenous thrombin potential + 192.62 nM.min (38.33, 326.91); P = 0.009; peak thrombin + 38.10 nM (2.27, 73.94); P = 0.034) but had increased overall fibrinolytic potential (+4.89% (0.52, 9.25); P = 0.024) compared with cisgender men. No significant changes were observed relative to cisgender women. Route of estradiol delivery or duration of use did not influence the GCA parameters.

Conclusion: Transgender women on estradiol therapy demonstrated hypercoagulable GCA parameters compared with cisgender men with a shift towards cisgender female parameters. Route of estradiol delivery did not influence the GCA parameters.

Keywords: coagulation; estrogen; global coagulation assays; thrombosis; transgender.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Administration, Cutaneous
Administration, Oral
Adult
Blood Coagulation Tests / methods*
Case-Control Studies
Cross-Sectional Studies
Estradiol / administration & dosage*
Female
Fibrin / analysis
Hormone Replacement Therapy*
Humans
Male
Middle Aged
Thrombelastography
Thrombin / analysis
Transgender Persons*

Substances

Estradiol
Fibrin
Thrombin