Wound Complications After Breast Reconstruction: The Limited Role of Hemoglobin A 1c Compared With Body Mass Index in Preoperative Risk Assessment.

Background: Hemoglobin A 1c (HbA 1c ) and body mass index (BMI) are routinely evaluated before both alloplastic and autologous breast reconstruction to assess postoperative complication risk. However, evidence-based guidelines regarding accepted cutoffs for these measures are limited. This study aimed to elucidate the associations between HbA 1c levels or BMI with wound complications following reconstructive breast surgery.

Methods: This retrospective cohort study utilized the American College of Surgeons National Surgical Quality Improvement Program database to assess 30-day wound complications among patients who underwent autologous or alloplastic breast reconstruction after mastectomy for breast cancer between January 1, 2021, and December 31, 2022. Wound complications included wound dehiscence, superficial incisional surgical site infections (SSIs), deep incisional SSI, or organ space SSI. Statistical analyses including multivariable Cox regression and Kaplan-Meier curve comparisons were performed based on the distribution of HbA 1c or BMI in the cohort.

Results: A total of 2809 patients underwent breast reconstruction with preoperative HbA 1c measurements. Among these, 2025 (72.1%) underwent alloplastic reconstruction, whereas 784 (27.9%) underwent autologous reconstruction. For the entire cohort, the median age was 54 years, the median HbA 1c was 5.7 (interquartile range, 5.3-6.4), and the median BMI was 29.4 kg/m 2 (interquartile range, 25.5-33.9). The 30-day complication rates in the autologous and alloplastic groups were 11.7% and 7.5%, respectively. Kaplan-Meier curves for the comparison of absolute risk of 30-day wound complications showed no significant differences between HbA 1c quartile curves (log-rank P = 0.46). For BMI, compared with the first quartile, the third (median BMI, 31.5 kg/m 2 ) and fourth quartiles (median BMI, 37.3 kg/m 2 ) had more than double the complication rates (Q1: 5.0%, Q2: 7.3%, Q3: 11.1%, Q4: 11.4%; P < 0.001). Adjusted hazard ratios for 30-day complication risk were 1.83 (95% confidence interval, 1.21-2.77; P = 0.004) for the third BMI quartile and 1.80 (95% confidence interval, 1.18-2.76; P = 0.007) for the fourth.

Conclusion: This study demonstrates that higher BMI is associated with wound complications after breast reconstruction. With the first BMI quartile as reference, patients in BMI quartile 4 had a 75% increased risk of complications in the alloplastic group, whereas the risk increased more than 1.4-fold in the autologous group. No similar associations were observed with HbA 1c levels.