Martin den Heijer

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Articles (11)

Objective Hormone therapy in transgender people might be associated with an increased risk of cardiovascular disease (CVD). We aimed to investigate whether the risk of CVD is increased in transgender people compared with people of the same birth sex. Design and methods PubMed, Cochrane, Embase, and Google Scholar were searched until July 2022. Studies evaluating cardiovascular events in transgender women or men were included. Primary outcomes were stroke, myocardial infarction (MI), and venous thromboembolism (VTE). The risk for transgender women versus cisgender men and for transgender men versus cisgender women was analysed through random-effects meta-analysis. Results Twenty-two studies involving 19 893 transgender women, 14 840 transgender men, 371 547 cisgender men, and 434 700 cisgender women were included. The meta-analysis included 10 studies (79% of transgender women and 76% of transgender men). In transgender women, incidence of stroke was 1.8%, which is 1.3 (95% confidence interval [CI], 1.0-1.8) times higher than in cisgender men. Incidence of MI was 1.2%, with a pooled relative risk of 1.0 (95% CI, 0.8-1.2). Venous thromboembolism incidence was 1.6%, which is 2.2 (95% CI, 1.1-4.5) times higher. Stroke occurred in 0.8% of transgender men, which is 1.3 (95% CI, 1.0-1.6) times higher compared with cisgender women. Incidence of MI was 0.6%, with a pooled relative risk of 1.7 (95% CI, 0.8-3.6). For VTE, this was 0.7%, being 1.4 (95% CI, 1.0-2.0) times higher. Conclusions Transgender people have a 40% higher risk of CVD compared with cisgender people of the same birth sex. This emphasizes the importance of cardiovascular risk management. Future studies should assess the potential influence of socio-economic and lifestyle factors.

Year:

2024

Context Liver fat content and visceral fat volume are associated with insulin resistance and cardiovascular disease and are higher in men than in women. Objective To determine the effect of estradiol and testosterone treatment on liver fat and visceral fat in transgender persons. Design Open-label intervention study (SHAMVA) with a 1-year follow-up. Setting Gender clinic in a hospital. Patients 8 trans women and 18 trans men receiving hormone treatment. Interventions Trans women received an antiandrogen and after 6 weeks estradiol was added. Trans men were randomized to receive triptorelin, testosterone, and anastrozole for 12 weeks or triptorelin and testosterone for 12 weeks, followed by only testosterone until week 52. Main outcome measures Liver fat content, visceral and abdominal subcutaneous fat volume, measured by magnetic resonance spectrometry or imaging at baseline, 6, 8, 18, and 58 weeks in transwomen or at baseline; at 6 and 12 weeks in trans men with anastrozole; and at 52 weeks in trans men without anastrozole. Results In trans women, liver fat content decreased by 1.55% (−2.99 to −0.12) after 58 weeks, compared to week 6. Visceral fat did not change. In trans men with anastrozole, the liver fat content and visceral fat volume did not change. In trans men without anastrozole, after 52 weeks, liver fat content increased by 0.83% (0.14 to 1.52) and visceral fat volume increased by 34% (16 to 51). Conclusions Sex hormones regulate liver fat content and visceral fat in men and women.

Year:

2023

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2023

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2023

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2023

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2023

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2023

Background Initiating feminizing gender-affirming hormone therapy (GAHT) in transgender women causes a steep decline in serum testosterone. It is unknown if testosterone concentrations change further and whether adrenal androgen levels change during feminizing GAHT and after gonadectomy. This limits clinical decision making in transgender women with symptoms attributed to GAHT or gonadectomy. Methods Transgender women (n = 275) initiating estradiol and cyproterone acetate (CPA) were included at baseline, and had follow-up visits after 3 months, 12 months, and 2 to 4 years. During follow-up, 49.5% of transgender women underwent a gonadectomy. Total testosterone (TT), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), and androstenedione (A4) were measured using liquid chromatography tandem mass spectrometry. Results After 3 months of GAHT, mean TT, calculated free testosterone (cFT), and A4 decreased by 18.4 nmol/L (95% CI, −19.4 to −17.4, P < 0.001 [ie, −97.1%]), 383 pmol/L (95% CI, −405 to −362, P < 0.001 [ie, −98.3%]), and 1.2 nmol/L (95% CI, −1.4 to −1.0, P < 0.001 [ie, −36.5%]), respectively, and remained stable thereafter. DHEA and DHEAS decreased by 7.4 nmol/L (95% CI, −9.7 to −5.1 [ie, −28.0%]) and 1.8 µmol/L (95% CI, −2.2 to −1.4 [ie, −20.1%]), respectively, after 1 year and did not change thereafter. After gonadectomy, CPA therapy is stopped, which induced no further change in TT, cFT, DHEA, DHEAS, and A4 compared with those who did not undergo gonadectomy. Conclusions Our findings confirm that after an initial drop, testosterone levels in transgender women remain stable. Adrenal androgens decrease in the first year of CPA and estrogen supplementation and remain unchanged after gonadectomy. Androgens did not change after gonadectomy and cessation of CPA. Correlates with clinical symptoms remain to be elucidated.

Year:

2022

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2022

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2022

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2022

Collaborators (6)

tom fiers

Ghent University Hospital

BELGIUM
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Annemieke C Heijboer

-

NETHERLANDS
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Daniel van Raalte

-

NETHERLANDS
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A.S. Paul van Trotsenburg

Amsterdam University Medical Centers

NETHERLANDS
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Peter H Bisschop

University of Amsterdam

NETHERLANDS
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Guy T'Sjoen

Ghent University Hospital

BELGIUM
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