Mental health treatment following gender-affirming surgeries: Evidence from longitudinal Australian administrative data

Introduction Gender incongruence in trans and gender-diverse (trans) populations is often associated with psychological distress and increased demand for mental healthcare. Gender-affirmation, including gender-affirming surgeries, may provide an effective long-term treatment option for many trans individuals, however longitudinal evidence on its effects on mental health treatment and government expenditure is scarce. This study explores the extent to which gender-affirming surgery is associated with changes in use of mental health services, prescriptions, and associated government costs.Methods This study used longitudinal whole-of-population Australian administrative data (2013–2024), including 3,698 trans adults who underwent gender-affirming chest or genital surgery. A dynamic difference-in-differences model was applied to estimate within-individual changes in mental health services and prescriptions (antidepressants, anxiolytics), and associated government costs five years after surgery, using future surgery recipients as controls. Effects were estimated separately for each surgery type relative to individuals’ outcomes two years before surgery.Results Gender-affirming surgeries were associated with a reduction in mental health treatment. Five years post-surgery, gender-affirming chest and genital surgery recipients respectively used 1.87 (95% CI 0.88; 2.80) and 5.03 (95% CI 3.62; 6.44) fewer mental health services per annum. Mental health prescription utilization also decreased for chest surgery recipients [1.26 (95% CI 0.42; 2.10) fewer prescriptions at five years] but were not significantly different to the reference period for genital surgery recipients [0.01 (95% CI −1.03; 1.06) at five years]. Annual government spending on mental healthcare decreased by AU$430 (95% CI 270; 591) [US$310 (95% CI 194; 425)] for chest surgery recipients and AU$884 (95% CI 545; 1,222) [US$636 (95% CI 392; 880)] for genital surgery recipients at five years.Conclusions Expanding gender-affirming surgery access may help improve mental health for trans individuals and reduce associated government spending. These results contribute new evidence to support the provision of gender-affirming surgeries for trans people who seek it.