UNUSUAL CAUSE OF BRANCH RETINAL ARTERY OCCLUSION: POLYCYTHEMIA IN A TRANSGENDER MAN FROM UNREGULATED TESTOSTERONE USE

Thrombotic risk associated with gender-affirming hormone therapy

Transgender and gender-expansive (TG) people-those who identify with a gender other than their assigned sex at birth-frequently experience gender dysphoria, which is associated with negative health outcomes. One key strategy for improving gender dysphoria is the use of gender-affirming hormone therapy (GAHT): estrogen for feminization and testosterone for masculinization. Estrogen use in cisgender women is associated with well-established changes in hemostatic parameters, including increases in prothrombotic factors and decreases in inhibitors of coagulation. Cisgender women using estrogen have an increased risk of thrombosis. Studies of thrombosis risk associated with estrogen GAHT in TG people are less robust, with some studies limited by the use of hormones and hormone management strategies that are no longer recommended. However, TG women using estrogen appear to be at increased risk of both arterial and venous thrombosis, which may increase with longer time on estrogen. Testosterone use in both cisgender and transgender men is associated with increases in hemoglobin and hematocrit, which can lead to erythrocytosis and thus increased risk of thrombosis. The results of studies evaluating thrombosis risk in the setting of testosterone use are mixed. This review presents an overview of alterations in hemostatic parameters and thrombosis risk associated with use of exogenous estrogen and testosterone. Understanding what is known and unknown about thrombosis risk associated with use of these hormones is essential for hematologists who may be asked to evaluate TG people and provide guidance on management of those who may be at increased risk of thrombosis.

Monitoring Haematocrit in Paediatric Patients Receiving Testosterone Therapy in Arab Countries

Objectives Testosterone is the main agent used to induce puberty in boys in Arab countries. It is recommended to monitor haematocrit before and during androgen replacement. However, data from single centre studies indicated that this recommendation is rarely practiced by paediatricians compared to adult physicians. The aim of this study is to evaluate the monitoring of haematocrit of patients on Testosterone therapy by paediatric endocrinologists practicing in Arab countries. Methods A cross-sectional study using an online survey that was sent to all members of the Arab Society for Paediatric Endocrinology and Diabetes (ASPED), who they practice in all Arab countries. The study was carried out between July and October 2019. Ethical approval was granted by ASPED council in May 2019 (MRE2019-02Q).  Results One hundred four physicians responded to the survey from 17 countries. 81/104 (77.8%) answered the question about Testosterone monitoring (42 paediatric endocrinologists, 11 general paediatrician consultants with interest in endocrine, 16 specialists, four fellows and eight residents). Of the 81 responders 18 clinicians (22.2%) thought of monitoring the haematocrit; 15 (18.5%) thought no laboratory monitoring is needed at all. Conclusion The survey indicated that most paediatric endocrinologists in Arab countries do not monitor haematocrit in patients on testosterone replacement and majority are not aware that secondary erythrocytosis can result from androgen therapy. Raising the awareness on monitoring haematocrit during androgen replacement therapy is needed especially when reaching the adult dose.

Longitudinal Changes in Hematologic Parameters Among Transgender People Receiving Hormone Therapy

CONTEXT

The effect of gender-affirming hormone therapy (HT) on erythropoiesis is an area of priority in transgender health research.

OBJECTIVE

To compare changes in hematologic parameters and rates of erythrocytosis and anemia among transgender people to those of cisgender controls.

DESIGN

Longitudinal observational study.

PARTICIPANTS AND SETTING

We compared 559 transfeminine (TF) and 424 transmasculine (TM) people enrolled in 3 integrated health care systems to matched cisgender referents.

INTERVENTIONS AND OUTCOME

Hormone therapy receipt was ascertained from filled prescriptions. Hemoglobin (Hb) and hematocrit (Hct) levels were examined from the first blood test to HT initiation, and from the start of HT to the most recent blood test. Rates of erythrocytosis and anemia in transgender participants and referents were compared by calculating adjusted hazard ratios and 95% confidence intervals (CI).

RESULTS

In the TF group, there was a downward trend for both Hb and Hct. The corresponding changes in the TM cohort were in the opposite direction. TM study participants experienced a 7-fold higher rate (95% CI: 4.1-13.4) of erythrocytosis relative to matched cisgender males, and an 83-fold higher rate (95% CI: 36.1-191.2) compared to cisgender females. The corresponding rates for anemia were elevated in TF subjects but primarily relative to cisgender males (hazard ratio 5.9; 95% CI: 4.6-7.5).

CONCLUSIONS

Our results support previous recommendations that hematological parameters of transgender people receiving HT should be interpreted based on their affirmed gender, rather than their sex documented at birth. The clinical significance of erythrocytosis following testosterone therapy, as well as anemia following feminizing HT, requires further investigation.