Increase in visceral adipose tissue and altered metabolic profile in transgender men but not in transgender women one year after starting gender-affirming hormonal therapy.

Testosterone therapy in AFAB persons led to a significant increase in visceral adipose tissue (VAT) after one year.

• The study included 50 assigned female at birth (AFAB) persons with a median age of 21.5 years.
• VAT increase was statistically significant at P = 0.0006.
• Trunk/limb ratio also increased significantly (P < 0.001).
• This was a single center retrospective study with data separated by a 1-year period.

Testosterone therapy in AFAB persons produced an adverse lipid profile, including increased LDL-cholesterol and decreased HDL-cholesterol.

• LDL-cholesterol increased significantly (P < 0.05).
• HDL-cholesterol decreased significantly (P < 0.05).
• Uric acid also increased significantly (P < 0.001).
• These changes collectively represent an altered and potentially pro-atherogenic metabolic profile.

Increase in uric acid explained 33.2% of the variation in VAT in AFAB persons receiving testosterone therapy.

• Results of the final regression models indicated that increase in uric acid explained 33.2% of the variation in VAT.
• F(1,15) = 7.458; adjusted R square 0.332; P = 0.015.
• This suggests uric acid may be a significant metabolic mediator in VAT accumulation during testosterone therapy.

No changes in systemic inflammatory indices were observed in AFAB persons one year after starting testosterone therapy.

• Despite significant changes in VAT and metabolic parameters, systemic inflammatory indices remained unchanged.
• This finding held true even with the increase in visceral adiposity, which is typically associated with pro-inflammatory states.
• The absence of inflammatory changes may reflect the relatively short one-year follow-up period.

AMAB persons receiving gender-affirming hormone therapy experienced increases in total body fat and fat mass index without adverse cardiometabolic changes.

• The study included 37 assigned male at birth (AMAB) persons with a median age of 29 years.
• Total body fat increased significantly (P = 0.002) and fat mass index increased significantly (P = 0.001).
• HDL-cholesterol increased (P < 0.05), representing a potentially favorable lipid change.
• The aspartate transaminase to lymphocyte ratio index (APRI) decreased (P < 0.05), suggesting reduced liver inflammation or fibrosis risk.
• AMAB persons were described as presenting 'a non-deleterious cardiometabolic phenotype.'