LAUSR

Importance Transgender and nonbinary (TGNB) adolescents and young adults (AYA) designated female at birth (DFAB) experience chest dysphoria, which is associated with depression and anxiety. Top surgery may be performed to treat chest dysphoria. Objective To determine whether top surgery improves chest dysphoria, gender congruence, and body image in TGNB DFAB AYA. Design, Setting, and Participants This is a nonrandomized prospective cohort study of patients who underwent top surgery between December 2019 and April 2021 and a matched control group who did not receive surgery. Patients completed outcomes measures preoperatively and 3 months postoperatively. This study took place across 3 institutions in a single, large metropolitan city. Patients aged 13 to 24 years who presented for gender-affirming top surgery were recruited into the treatment arm. Patients in the treatment arm were matched with individuals in the control arm based on age and duration of testosterone therapy. Exposures Patients in the surgical cohort underwent gender-affirming mastectomy; surgical technique was at the discretion of the surgeon. Main Outcomes and Measures Patient-reported outcomes were collected at enrollment and 3 months postoperatively or 3 months postbaseline for the control cohort. The primary outcome was the Chest Dysphoria Measure (CDM). Secondary outcomes included the Transgender Congruence Scale (TCS) and Body Image Scale (BIS). Baseline demographic and surgical variables were collected, and descriptive statistics were calculated. Inverse probability of treatment weighting (IPTW) was used to estimate the association of top surgery with outcomes. Probability of treatment was estimated using gradient-boosted machines with the following covariates: baseline outcome score, age, gender identity, race, ethnicity, insurance type, body mass index, testosterone use duration, chest binding, and parental support. Results Overall, 81 patients were enrolled (mean [SD] age, 18.6 [2.7] years); 11 were lost to follow-up. Thirty-six surgical patients and 34 matched control patients completed the outcomes measures. Weighted absolute standardized mean differences were acceptable between groups with respect to body mass index, but were not comparable with respect to the remaining demographic variables baseline outcome measures. Surgical complications were minimal. IPTW analyses suggest an association between surgery and substantial improvements in CDM (-25.58 points; 95% CI, -29.18 to -21.98), TCS (7.78 points; 95% CI, 6.06-9.50), and BIS (-7.20 points; 95% CI, -11.68 to -2.72) scores. Conclusions and Relevance Top surgery in TGNB DFAB AYA is associated with low complication rates. Top surgery is associated with improved chest dysphoria, gender congruence, and body image satisfaction in this age group.