Gender affirming hormone therapy is generally continued lifelong, so understanding any potential risks and finding ways to mitigate them is essential. While research in this area is in its infancy, there is growing interest in systems that are highly regulated by sex hormones including metabolic and bone health.
In the limited studies to date, transgender adults appear to have a higher risk of cardiovascular disease.1 It is unclear whether hormone therapy is causal, and modern gender-affirming hormone therapy formulations likely confer a lower risk of cardiovascular disease than the regimens historically studied. Monitoring of cardiovascular risk is performed through baseline and then annual biochemistry, as well as physical examination (blood pressure, weight, body mass index).2 Counselling the patient on what is known, and not yet known, about cardiovascular risk as well as the contributing factors so that primary prevention strategies may be implemented. In addition to smoking cessation, regular exercise, and dietary interventions, optimisation of insulin resistance, lipid profile, and blood pressure is recommended with onward referral on for more specialised cardiovascular assessment if the patient is considered high risk.2
Bone health appears to be maintained for those on masculinizing hormone therapy regimens, indicating estradiol (via aromatisation of administered testosterone) is sufficient to preserve bone microarchitecture.3 Conversely, higher fracture rates and unfavorable bone microarchitectural parameters are associated with feminising hormones.3,4 Screening and monitoring of bone health is particularly important in those individuals at higher risk (such as individuals previously on medications to induce pubertal blockade, and those on androgen blocking agents or prior gonadectomy with inadequate replacement sex hormone levels.
To accurately understand cardiovascular and bone health in transgender adults, additional high-quality research that evaluates modern hormone therapy regimens whilst also controlling for potential confounding factors are needed.