Synergistic Interaction Increases Complication Rates following Microvascular Breast Reconstruction

Area of Science:

• Plastic Surgery
• Surgical Oncology
• Reconstructive Surgery

Background:

• Microvascular breast reconstruction is complex with high complication rates.
• Individual risk factors are known, but their interactions are less understood.
• Accurate preoperative risk prediction requires understanding synergistic effects of multiple risk factors.

Purpose of the Study:

• To investigate the synergistic interactions between patient- and treatment-related risk factors for perioperative complications in microvascular breast reconstruction.
• To identify combined risk factors that significantly increase complication rates.

Main Methods:

• Retrospective cohort study of 912 patients undergoing microvascular breast reconstruction (2009-2017).
• Multivariable logistic regression identified independent predictors of complications.
• Relative Excess Risk Index (RERI) and Synergy Index (SI) assessed interactions between variables.

Main Results:

• 26.1% of patients experienced perioperative complications.
• Obesity, immediate reconstruction, and comorbidities were independent predictors.
• Significant synergistic interactions were found between obesity/comorbidities and immediate reconstruction, bilateral reconstruction, and prior radiotherapy.
• Obese smokers undergoing immediate reconstruction had a 12-fold increased complication risk due to strong synergy.

Conclusions:

• Patient and treatment variables interact synergistically to elevate complication risk in microvascular breast reconstruction.
• These interactions are critical for accurate preoperative risk stratification.
• Personalized risk assessment should consider combined effects of multiple risk factors.