Introduction
According to the 10th revision of the International Statistical Classification of
Diseases and Related Health Problems (ICD-10), transsexualism (F64.0) is defined as
a condition in which an individual self-identifies and desires to have physical characteristics
and social roles that connote the opposite biological sex.[1] Gender incongruence is the proposed name of the gender identity-related diagnoses
in the 11th revision of the ICD (ICD-11). Not all individuals with gender incongruence
have gender dysphoria or seek treatment. According to the 4th Edition of the Diagnostic and Statistical Manual of Mental Disorders(DSM-4) from
the American Society of Psychiatry, in the gender identity disorder, the individual
manifests marked anxiety, discomfort and suffering, because of the desire to live
and be accepted as someone with the opposite gender than the one designated at birth,
independently of the sexual orientation. Recently, on the 5th Edition of the DSM (DSM-5), the term “gender identity disorder” was substituted for “gender dysphoria” (GD).[2]
[3]
Usually, these individuals manifest a strong desire to define a social identity and
redesign their physical appearance according to the gender of identification by means
of hormonal therapy and/or surgical procedures.
The recognition and acceptance of transgender women (individuals 46 XY, with male
phenotype and female identity) and transgender men (individuals 46 XX, with female
phenotype and male identity) have increased in the last decade, both among health
providers and among the general population.[2]
In the Brazilian Public Health System (SUS, in the Portuguese acronym), the transsexualization
process was institutionalized by means of the ministerial order SAS/MS-457, stated
on August 19th, 2008. This determination established guidelines to regulate clinical and surgical
procedures that could be used to adapt the genital status to match gender identification
in transgender individuals. In 2010, the Brazilian Federal Council of Medicine (CFM,
in the Portuguese acronym), by means of the 1995/2010 resolution, authorized and amplified
the surgical procedures for sexual reassignment, since these procedures were officially
approved by the Ministry of Health (MS, in the Portuguese acronym). After that, on
November 19th, 2013, a new determination published by the MS, GM/MS 2,803,[4] redefined and amplified the management of the transsexualization process in the
SUS, which now, besides including new procedures, also allowed a larger number of
health centers to be enabled to offer treatment to this population. Nowadays, centers
registered to offer medical assistance to transgender individuals must be capable
of offering integral care, from the primary care to the specific and specialized assistance,
in a multidisciplinary and interdisciplinary effort. According to the World Professional
Association for Transgender Health (WPATH)[5] and the MS in Brazil (regulatory ordinance n° 2.803, 2013 November 19th Art. 13),[4] it is recommended that the gender affirmation process is performed by a team composed
of a social assistance provider, mental health professionals (psychiatrist and psychologist),
an endocrinologist, a gynecologist and a plastic surgeon, while the diagnosis and
treatment are being determined.[4]
[5]
In addition, the centers that provide health assistance for this specific population
must be connected to the SUS network, making the primary care centers the principal
access to the health system. According to the offered protocol, in order to be submitted
to a surgical procedure for sexual reassignment, an individual must be at least 21
years old, and have no less than 1 year of hormonal therapy and a 2-year follow-up
with a mental health professional. It is important to distinguish, during the psychological
evaluation, transgender dysphoria from other mental disorders that present with similar
manifestations, as well as to identify and precisely treat psychiatric conditions
that may be generated by the incongruence between gender identity and biological sex,
such as anxiety, depression, auto-mutilation, compulsive behavior, drug abuse, personality
and alimentary disorders and also autism spectrum disorders.[5] Thus, it has been proposed that the diagnostic might be confirmed by a mental health
professional who recommends hormonal therapy for those transgender individuals that
desire to use it.[5]
[6]
Recommendations for the Use of Testosterone in Male Transgenders
The testosterone treatment's main goal is to start the development of male physical
characteristics. The androgenization may be offered to transgender men who are 18
years old or older and who have characteristics of gender dysphoria/gender incongruence,
which must be attested by a mental health professional, and who also are completely
capable of deciding to receive or not an individualized treatment, based on cost/benefit
ratio, on social and economic issues and on individual specific necessities.[5] The use of androgens for virilization is usually well tolerated and improves the
quality of life and reduces the self-acceptance conflicts. However, there is still
lack of evidence regarding the psychological effect of the long-term use of these
hormones.[7] The transgender men, before starting treatment, must be informed about the limitations
and possible side effects that might advent from the androgen administration, such
as irreversible physical alterations and the risk of infertility, although the severity
and reversibility of this last side effect are not yet completely clarified.[2] Some physical results may not be achieved, despite the dose of testosterone used;
furthermore, the intentional use of supra physiologic doses of this hormone, greater
than the male pattern, may lead to increased risk of complication.[7]
The best moment to start the androgenic therapy is usually defined in collective agreement
between the transgender individual that aims to start the transsexualization process
and the mental health team that assisted him, diagnosed the gender dysphoria condition
and recommended his sexual reassignment.[5]
[6]
[8]
Many different pharmacological formulations have been used by the health care services
in the transsexualization process, including intramuscular testosterone esters in
a short term or long-term release injection, undecanoate testosterone capsules, testosterone
gel, patches or subcutaneous systems. Not every option is available for therapy in
Brazil.[9] Oral testosterone (17 methyltestosterone or fluoximetazona) is not recommended because
of excessive liver toxicity. The transdermal formulations, in gel or patch form, simulate
the physiological release of testosterone, with minimal plasmatic oscillations. Usually,
the side effects related to the transdermal use are secondary to skin-to-skin contact
in the gel form and cutaneous irritation in the patch form. Both presentations are
high-cost drugs and the patch is not available in Brazil. The oral administration
of undecanoate testosterone, 80 to 160 mg/day, is not associated with hepatotoxic
effect, and its intramuscular long-term release injection, 800 to 1,000 mg every 12
weeks, keeps the plasmatic levels stable, with no peaks after administration. This
drug is approved and available for therapy in Brazil, but its prohibitive cost makes
it impracticable as a regular treatment, especially in the public health system. The
most common used formulation is the intramuscular testosterone esters in a short-term
release injection, the testosterone cypionate or enanthate, 200 mg every 2 or 3 weeks.
These are low-cost drugs and offer good tolerance and satisfactory clinical response,
although they are not able to simulate the circadian rhythm and induce a supraphysiologic
testosterone plasmatic level on the 1st days after administration ([Table 1]).[2]
[10]
Table 1
Testosterone formulations
|
Composition
(testosterone)
|
Dose
|
Advantages
|
Disadvantages
|
|
Cypionate or Enanthate
Intramuscular route
|
200 mg every
2–3 weeks
|
Low cost
|
Does not mimic testosterone circadian rhythm
Plasmatic levels of testosterone reach high non-physiological levels (800–1,000 ng/dL)
in the first days after administration
|
|
Undecanoate testosterone
oral route
|
60–160 mg /day
|
Safe
(no hepatotoxicity)
|
2–4 daily doses
|
|
Undecanoate testosterone
intramuscular route
|
800–1,000 mg every 12 weeks
|
Stable concentrations
Physiologic doses
|
High cost
|
|
Gel (1%) (topic application)
|
25–100 mg/day
|
Stable concentrations
|
High cost
|
|
Skin-to-skin contact transference
|
|
Not available in Brazil
|
|
Patch (topic application)
|
2.5–10 mg/day
|
Stable concentrations
|
High cost
|
|
Skin irritation
|
|
Not available in Brazil
|
The androgenic therapy usually has a benefic psychological effect in transgender men,
reducing anxiety, depression, emotional lability and humor disorders, probably due
to the presence of androgen receptors all over the central nervous system.[2] Although this improvement in psychological health may be due to a direct testosterone
effect, it is more likely that this benefit on psychological symptoms are secondary
to a reduction in the dysphoria caused by the physical alterations in response to
the androgen therapy.[9] Some transgender man still present with signs of anxiety and depression, even after
the hormonal induced physical changes are complete, mainly those individuals who desire
to have a surgical procedure for transsexualization.
In the majority of the testosterone therapy protocols, the male physical characteristics
can be seen in almost all users after 6 months of therapy, and the maximum virilization
effects are usually achieved after 3 to 5 years of regular use of the hormone.[11] The increase in facial and corporal hair according to the male pattern can be observed
after 4 to 6 weeks of treatment. Testosterone also progressively increases the hair
follicle density, the thickness and the hair growth rate.[5]
[9]
[11] However, as testosterone acts directly in the pilosebaceous unit, the hair growth
rate is usually associated with acne and, in individuals with specific genetic predisposition,
a long-term use can induce alopecia.[9] Another collateral effect that may occur as a consequence of androgenic therapy
is clitoromegaly (3.5–5.0 cm), which can be associated with pain in 20% of the cases,
especially in those transgender men treated with undecanoate testosterone.[9]
Testosterone treatment seems to be associated with an increase in sexual desire of
transgender men. A prospective study evaluating transgender men, with no history of
psychiatric diseases or use of medication, who were submitted to different types of
testosterone formulations in one year, demonstrated an increase in sexual desire,
sexual fantasies and masturbation frequency in 70% of the individuals. However, no
increase in the frequency of intercourse or in sexual satisfaction was reported.[12]
Voice alterations, similar to those observed in male puberty, have also been observed
in male transgender after 3 to 6 months of treatment. Commonly, the voice gets deeper,
although almost one third of male transgenders will need speech therapist support
because of voice fatigue, instability, quality and projection.[9]
Testosterone therapy also modifies the body composition toward a male pattern, in
general with higher muscular mass and lower adipose mass than females. A period of
up to 2 years of androgen administration is needed to produce a redistribution of
body fat with more pronounced truncal adiposity. An increase in 1.5 to 6.0 Kg of lean
mass may also occur, with a correspondent increase in muscular strength and a reduction
in 2 to 4 Kg in body fat.[13]
Typically, testosterone can induce alteration in the vaginal epithelium, clinically
manifested by signs of mucosa atrophy. Transgender men treated with intramuscular
testosterone presented a thinner vaginal epithelium, with loss of superficial and
intermediate layers and intracytoplasmic glycogen reduction, similar to that observed
in postmenopausal women.[5]
One of the main goals of transgender men under androgen therapy is the achievement
of amenorrhea, which contributes enormously to the psychological well-being in these
individuals. With the usual recommended therapeutic doses, amenorrhea will occur in
90% of the patients in the first 6 months, reaching almost 100% after 1 year of treatment.[8] Although menstrual cycles are suspended, the endometrial evaluation in male transgenders
has shown inconsistent results. In one study, all the evaluated samples indicated
inactive endometrium, similar to the endometrium seen in postmenopausal women but
in another study, only half of the patients presented atrophic endometrium, while
in the other half a proliferative endometrium was found even after 2 to 9 months of
androgenic therapy.[9]
Even though the role of androgenic therapy on the ovaries has been widely discussed,
no definitive conclusions were made. Testosterone may lead to stromal hyperplasia
and increase ovarian volume, which assumes a polycystic morphology, defined by the
presence of 12 or more preantral follicles per ovary, in mostly all transgender men.
However, more recent data have shown that the ovarian morphology in these individuals,
analyzed by tridimensional ultrasound, does not differ from the ovaries of cycling
women, suggesting that androgen therapy in transgender man does not necessarily induce
a polycystic ovary morphologic pattern.[14]
Mammary tissue is another target that seems to have its composition altered by testosterone
therapy.[9] Histological analyses of mammary tissues from androgen treated transgender men submitted
to mastectomy during the transsexualization process have evidenced a substantial reduction
in glandular and adipose tissues and an increment in the fibrous connective tissue.
No atypical hyperplasia or carcinoma were reported during a follow-up of 19 years
under androgen therapy.[15] The estimated risk of breast cancer in transgender men under testosterone therapy
is 5.9 (0.5–27.4) cases per 100,000 persons/year, while this risk for normal women
is 155 cases per 100,000 women/year.[15] More studies are necessary to confirm these data.
Other comorbidities, such as sleep apnea, impairment in lipid profile, insulin sensitivity
reduction, polycythemia, venous thromboembolism, arterial hypertension and atherosclerosis,
can be worsen or be initiated by the chronic use of androgen therapy, potentially
increasing cardiovascular risk.[16] However, the use of different testosterone formulations does not seem to affect
the systemic arterial blood pressure, the carotid intima media layer thickness nor
the deposition of calcium in the coronary arteries. Also, no effect on fasting glucose,
intensity of insulin resistance, or venous thromboembolism risk has been reported.[9]
[16] A recent meta-analysis concluded that the cardiovascular risk evaluation in transgender
men submitted to androgen therapy is limited due to several weaknesses: low level
of evidence obtained from a few observational studies, lack of control group, small
subjects number, comparison of different androgen therapy protocols, short-term follow-up
and beginning of therapy before 30 years of age, when the cardiovascular risk itself
is naturally very low.[17]
It is recommended that transgender men under androgen therapy should be monitored
for cardiovascular risk every 3 months during the 1st year after treatment initiation
and then every 6 to 12 months. The protocols suggested by the Endocrine Society Clinical
Practic[8] and the WPATH[4] recommend that, to minimize risks, plasmatic testosterone levels should be kept
within male physiological ranges (300–1,000 ng/dl) during hormonal treatment. Gonadotrophin
levels can be suppressed, but in some cases, they can be above normal follicular phase
ranges, suggesting that the hypothalamus-hypophysis-ovary (HHO) axis may not be suppressed
by male physiologic levels of androgen.[1] This reinforces the importance of contraceptive measures for transgender men that
practice penis-in-vagina intercourse with men or transgender women. Estradiol measurement
during the first 6 months of therapy may help monitoring the activity of the HHO,
once suppressed levels of estradiol (< 50 pg/ml) associated to amenorrhea suggests
a blocked axis.[16] Concentrations of estradiol < 3 0 pg/ml combined with FSH > 40 UI/l might be better
markers of ovarian suppression.
It is recommended that testosterone levels be measured 7 to 10 days after intramuscular
testosterone esters injection, nearby the nadir levels or at any time after 1 week
of transdermal androgen use. Estradiol levels shall be evaluated after 6 months of
treatment or after amenorrhea is installed. From the metabolic point of view, blood
pressure, lipid profile, fasting glucose and hematocrit shall be monitored before
and every 3 months on the 1st year of androgen therapy.[8] Because testosterone can be aromatized in estradiol, its long-term effects on ovary,
uterus and breast are not completely defined, thus screening for endometrial, ovarian,
and breast cancer shall be performed in agreement with the particularities of each
case. A pelvic ultrasound may be performed every 6 months or whenever the health assistance
provider believes it is necessary.[1]
[8]
[12]
According to the literature, it seems that androgen therapy for transgender men may
be prescribed for the whole life. There is not enough evidence to determine if this
is the best treatment for all transgender individuals or only for those submitted
to oophorectomy.
A higher overall mortality has been described in transgender individuals, but available
data cannot establish a cause and effect correlation between long-term use of testosterone
as the main cause of death in this population; instead, it suggests that drug abuse,
sexually transmitted diseases (STDs), mainly HIV-AIDS, and suicide are more frequent.
Thus, in addition to HIV, hepatitis, and other STD screening, it is recommended that
mental disorders screening should also be included in the routine follow up of transgender
men, because of its high prevalence in this population who live under the chronic
stress that is still imposed on some minorities.[5]
[6]
