The purpose of this study is to test whether and how a person's brain changes in the first few months after starting gender affirming hormone therapy (GAHT). The investigators want to know if GAHT changes: 1) cerebral blood flow (CBF), 2) brain structure, connectivity, and cognitive task performance, and 3) neurocognitive function (memory, attention, executive function, processing speed). 36 male at birth and 36 female at birth participants will conduct baseline studies prior to GAHT, with a second identical set of study visits 4-6 months after GAHT begins.
The purpose of this study is to assess the effects of GAHT on cerebral structure and function. To this end, this study has three aims: Aim 1: To identify if transgender males and females demonstrate changes in * A) basal CBF and * B) CBF responses to acute stress-particularly in areas involved in cognition, memory, and learning. Aim 2: To identify if transgender adults will demonstrate significant changes in: * A) overall brain structure, * B) functional connectivity, and * C) task activation. Aim 3: To identify if neurocognitive function changes in transgender adults. The investigators hypothesize that: * Aim 1: Transgender females will demonstrate increased basal CBF and larger CBF responses to acute stress, particularly in areas involved in cognition, memory, and learning, whereas transgender males will display lower basal CBF and lower CBF responses to acute stress. * Aim 2: Transgender patients will demonstrate significant changes in: a) overall brain structure, b) functional connectivity, and c) task activation. * Aim 3: Neurocognitive function will increase in transgender females and decreases in transgender males, primarily in the domains of memory, attention, executive function, and processing speed.
Study Type
OBSERVATIONAL
Enrollment
72
Two MRI visits (baseline and after 4-6 months of continuous GAHT) will involve structural scans of the brain, scans while performing cognitive tasks, and a scan taken while responding to an inhaled CO2 stressor. This visit will take approximately 1.5 hours.
Two cognition and health test trials (baseline and after 4-6 months of continuous GAHT) will involve a body composition scan to determine body fat percentage, muscle mass, and bone density. This will be followed by a set of cognitive tasks using the NIH Toolbox.
Optional graded exercise test will be performed if the participant consents to this optional procedure (baseline and after 4-6months of continuous GAHT). to determine cardiorespiratory fitness. This test will be performed on a cycle ergometer, with a metabolic allowing for the measurement of maximal oxygen consumption via indirect calorimetry.
UW School of Medicine and Public Health
Madison, Wisconsin, United States
RECRUITINGChange Cerebral Blood Flow (CBF)
CBF at rest and in response to cognitive stressors.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Brain Structure
Grey matter and White matter volumes.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Brain Connectivity
Measured using MRI.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Cognitive Function: Flanker Inhibitory Control and Attention
NIH Toolbox to assess neurocognitive function. The Flanker test is a measure of executive function and is scored using a T-score where 100 is the average, higher scores indicate better performance.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Cognitive Function: Pattern Comparison Processing Speed Test
NIH Toolbox to assess neurocognitive function. The Pattern Comparison Processing Speed Test measures how many correct responses the participant has within 90 seconds. There is a maximum of 130 items.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Cognitive Function: List Sorting Working Memory Test
NIH Toolbox to assess neurocognitive function. The List Sorting Working Memory Test is a measure of recall and sorting. Participants scores reflect the number of items recalled and appropriately sorted up to 28 items maximum.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Cognitive Function: Dimensional Change Card Sort Test
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
NIH Toolbox to assess neurocognitive function. The Dimensional Change Card Sort Test measures accuracy: the number of accurate responses, up to a maximum of 40.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Cognitive Function: Picture Vocabulary Test
NIH Toolbox to assess neurocognitive function. The Picture Vocabulary Test has the participant hear a word and then pick from one of four pictures that best represents the word. It is scored using a T-score where 100 is the average, higher scores indicate better performance.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change Cerebral Blood Flow (CBF)
Changes in CBF in response to inhaled mixture of room air and CO2
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Changes in sex steroid concentrations
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Body Composition
Dual-energy X-ray absorptiometry (DEXA)
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Blood Glucose
Glucose is a marker of metabolic health
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Insulin
Insulin is a marker of metabolic health.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Change in Cytokines
Cytokines are a marker of inflammation.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)
Optional Graded Exercise Test: VO2 Max
An optional graded exercise test will be performed to determine cardiorespiratory fitness. This test will be performed on a cycle ergometer, with a metabolic allowing for the measurement of maximal oxygen consumption via indirect calorimetry. This will be a ramped exercise test, starting at a wattage of 50W and increasing in difficulty by 1 watt every 2 seconds. The purpose of this is to begin at a low intensity and gradually increase the difficulty until exhaustion is reached.
Time frame: baseline and up to 6 months (after 4-6 months of continuous GAHT)