The Impact of BMI on Postoperative Complications Following Reduction Mammaplasty.

[BACKGROUND] Reduction mammaplasty alleviates the physical and psychosocial burden of macromastia. Elevated body mass index (BMI) is often cited as a risk factor for postoperative morbidity, yet its independent effect remains unclear.

[METHODS] A retrospective review of 952 patients (1,904 breasts) undergoing bilateral reduction mammaplasty by a single surgeon (2002-2024) was performed. Patients were stratified into World Health Organization BMI categories. Outcomes of interest included minor (not requiring readmission or reoperation) or major (requiring readmission or reoperation) complications. Logistic regression analyses were conducted, adjusting for diabetes, hypertension, smoking (active or prior), and prior radiation.

[RESULTS] The mean BMI was 34.0 (17.85-72.6). Overall, 278 (29.2%) patients experienced complications: 153 minor and 125 major. Minor complications increased stepwise with BMI (normal weight 4.7% vs obesity class III 31.2%, p<0.001). On multivariable analysis, obesity class II (OR 2.67, 95% CI 1.19-6.82) and class III (OR 3.40, 95% CI 1.50-8.80) independently predicted minor complications. BMI was not independently associated with major complications. Instead, hypertension (OR 1.70, 95% CI 0.99-2.86, p=0.05), active smoking (OR 2.13, 95% CI 1.08-3.98, p=0.02), and prior smoking (OR 2.94, 95% CI 1.04-7.27, p=0.03) predicted major complications.

[CONCLUSION] BMI independently predicts minor wound-related complications but not major complications. Major morbidity is more strongly influenced by comorbidities such as hypertension and smoking. These findings support individualized risk assessment and comorbidity optimization rather than rigid BMI cutoffs when counseling patients for reduction mammaplasty.