About this trial

It is known from the literature that women and men differ in their perception of pain. Why this is the case has not been conclusively clarified. Sex hormones could have a significant influence on this. The study team suspects that the classic hormone status of women is responsible for the lower pain threshold compared to men.

People undergoing gender affirming therapy receive biologically opposite-sex hormones in order to adapt their external appearance as well as their voice, emotional life etc. to the desired gender. The aim of this study is to longitudinally record whether the intake of opposite-sex sex hormones leads to a change in pain and perception thresholds in this patient collective. To this end, potential study participants will be informed about the study and asked whether they would like to participate before the start of hormone therapy during their first visit to the transgender outpatient clinic.

If consent is given, a questionnaire on mental health (PHQ 9), a blood sample to determine the hormone status and the first QST (quantitative sensory testing) measurement are then carried out. The second measurement with blood sampling takes place 3-4 weeks after the first measurement. The 3rd and 4th measurements with blood sampling are taken 3 and 6 months respectively after the first measurement. The PHQ 9 is measured again at the time of the last measurement. Study participation ends after a total of 6 months. The blood samples, the PHQ 9 and the QST measurements have no influence on the treatment of the study participants.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

≥ 18 years of age

Assigned female at birth (AFAB)

Diagnosed gender identity disorder/gender dysphoria and planned therapy with testosterone OR

≥ 18 years of age

Disqualifiers

Any sex hormone intake during the last 6 months

Acute or chronic pain

Polyneuropathy

Diagnosis of alcohol or drug addiction

Trial population

The study population will consist of adult participants, who must meet all of the prespecified inclusion criteria to be eligible for inclusion in the study and must not meet any of the prespecified exclusion criteria.

Trial design

Design model

Cohort

Time perspective

Prospective

Treatments tested in this trial

Quantitative Sensory Testing
Diagnostic test
Quantitative sensory testing (QST) is a psychophysical test procedure. With the help of calibrated stimuli and subjective sensory information, the functional state of the somatosensory system of a subject or patient is examined with regard to the expression of clinical signs. The test includes: * Cold detection threshold * Warm detection threshold * Paradoxical heat sensation * Cold pain threshold * Heat pain threshold * Mechanical detection threshold * Mechanical pain threshold * Mechanical pain sensitivity * Dynamic mechanical allodynia * Wind-up phenomena * Vibration threshold * Pressure pain threshold
Patient Health Questionnaire 9
Diagnostic test
The Patient Health Questionnaire 9 (PHQ-9), a validated and internationally used health questionnaire, will also be completed twice at the first study day before the sex hormone therapy is initiated and during the last study day in month 6. The questionnaire consists of 9 items on the topic of mental well-being.
Hormone concentrations
Diagnostic test
Blood concentrations of the following laboratory parameters will be determined: * Follicle stimulating hormone (FSH) * Luteotropic hormone (LH) * Prolactin (PRL) * Oestradiol (E2) * Sex hormone-binding globulin (SHBG) * Testosterone

Treatment groups

40 Participants

are divided into 2 treatment groups

Group A: AFAB Group3 interventions

Group B: AMAB Group3 interventions

Trial outcomes

Primary outcomes

1

Cold detection threshold

°C (Arithmetic mean after 3 measurement repetitions) With the Limits Method, the perception and pain thresholds are recorded as the first detected stimulus in the context of increasing stimulus intensities. This test will be performed with the Thermal Sensory Analyzer (TSA II, Medoc). A thermode equipped with a Peletier element and a cooling water supply is placed on the skin. Then the following parameters are determined using the Limits method: * Cold detection thresholds * Heat detection thresholds * Thermal difference thresholds for the detection of paradoxical heat sensations The contact area of the respective thermodes is 9.0 cm². By pressing a stop switch, which is connected to a computer unit, a threshold value determination can be made after a continuous ascending or descending temperature range with the thermode contact area, starting from a base temperature of 32°C. The temperature changes at a rate of 1°C/s.

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

2

Warm detection threshold

°C (Arithmetic mean after 3 measurement repetitions) With the Limits Method, the perception and pain thresholds are recorded as the first detected stimulus in the context of increasing stimulus intensities. This test will be performed with the Thermal Sensory Analyzer (TSA II, Medoc). A thermode equipped with a Peletier element and a cooling water supply is placed on the skin. Then the following parameters are determined using the Limits method: * Cold detection thresholds * Heat detection thresholds * Thermal difference thresholds for the detection of paradoxical heat sensations The contact area of the respective thermodes is 9.0 cm². By pressing a stop switch, which is connected to a computer unit, a threshold value determination can be made after a continuous ascending or descending temperature range with the thermode contact area, starting from a base temperature of 32°C. The temperature changes at a rate of 1°C/s.

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

3

Thermal sensory limen

°C With the Limits Method, the perception and pain thresholds are recorded as the first detected stimulus in the context of increasing stimulus intensities. This test will be performed with the Thermal Sensory Analyzer (TSA II, Medoc). A thermode equipped with a Peletier element and a cooling water supply is placed on the skin. Then the following parameters are determined using the Limits method: * Cold detection thresholds * Heat detection thresholds * Thermal difference thresholds for the detection of paradoxical heat sensations The contact area of the respective thermodes is 9.0 cm². By pressing a stop switch, which is connected to a computer unit, a threshold value determination can be made after a continuous ascending or descending temperature range with the thermode contact area, starting from a base temperature of 32°C. The temperature changes at a rate of 1°C/s.

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

4

Paradoxical heat sensation

Number of Paradoxical heat sensation out of 3 The paradoxical heat sensations (PHS) can occur during the determination of the TSL (thermal sensory limen) by thrice alternating cold and warm stimuli. A paradoxical heat sensation occurs when the patient expresses heat perceptions during an actual cold stimulus, contrary to what is indicated by the software, or vice versa. In the aforementioned thermal threshold measurement, alternating high and low temperatures are set on the thermode. The study participant does not know the sequence and must recognize the respective tendency. Alternating the temperature changes is done without resetting the initial temperature. PHS has no unit, it is given as a number: PHS 0; 1; 2 or 3, depending on the number of false temperature perceptions.

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

Secondary outcomes

1

Patient Health Questionnaire 9

Consists of 9 items concerning patient mental well-being. The EQ-5D-5L, a validated and internationally used health questionnaire, will also be completed twice at the first study day before the sex hormone therapy is initiated and during the last study day in month 6. It consists of a page with questions on mobility, self-care, usual activities, pain/discomfort and anxiety/depression as well as an assessment of one's own state of health on a scale of 1-100 (100 = best health you can imagine).

Time frame

At the time of enrollment and on the last study day after 6 months.

2

Hormone concentrations (follicle stimulating hormone)

Laboratory measurement of follicle stimulating hormone (FSH) in mIU/mL

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

3

Hormone concentrations (luteotropic hormone)

Laboratory measurement of luteotropic hormone (LH) in mIU/mL

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

4

Hormone concentrations (prolactin)

Laboratory measurement of prolactin (PRL) in ng/mL

Time frame

At the time of enrollment and after 3-4 weeks, 3 months and 6 months.

Perception of Pain During Gender Affirming Hormone Therapy

About this trial

Eligibility criteria

Qualifiers

Disqualifiers

Trial population

Trial design

Treatments tested in this trial

Treatment groups

Trial outcomes

Primary outcomes

Secondary outcomes

Other outcomes

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