Association of Body Mass Index With Postoperative Complications After Chest Masculinization Surgery: An Updated Analysis.

Abstract

Institutional preoperative body mass index (BMI) cutoffs for chest masculinization surgery (CMS) lack standardization and are based on limited data. After our group's NSQIP study found no severe morbidity or mortality in patients of higher BMI, we eliminated BMI cutoffs and collected additional measurements such as aesthetic and wound healing outcomes. This is a single-institution follow-up study to evaluate CMS outcomes in higher BMI patients to better guide preoperative planning and patient counseling. We conducted a retrospective, single-surgeon cohort study of patients who underwent CMS with double-incision mastectomy and free nipple grafting between November 2022 and January 2025, after elimination of BMI cutoffs. Primary outcomes included postoperative surgical complications requiring intervention and adverse aesthetic outcomes. We also collected major complications (e.g., venous thromboembolism, pulmonary embolism, sepsis, acute kidney injury). We analyzed BMI as both a continuous and a categorical variable per WHO guidelines, adjusting for confounders. Among 92 patients, the mean (SD) BMI was 32.2 (7.3) kg/m 2 . Surgical complications occurred in 20.7% (n = 19) of patients, of which most were superficial surgical site infections (12.0%, n = 11). No major complications occurred except for one case requiring blood transfusion for postoperative anemia (1.1%). Each 1-kg/m 2 increase in BMI was associated with 10% higher odds of infection (aOR, 1.10; 95% CI, 1.01-1.20; P = 0.029). Adverse aesthetic outcomes occurred in 32.6% of patients (n = 30), with each 1-kg/m 2 BMI increase associated with 12% higher odds of scar widening/hypertrophy and standing cone deformity (aOR, 1.12; 95% CI, 1.04-1.20; P = 0.002). Higher BMI was associated with increased risk of surgical site infection and adverse aesthetic outcomes following CMS. Major complications remained rare. Surgeons should avoid using BMI as an absolute contraindication and adopt a risk-stratified approach to guide care.