From the Division of Plastic and Reconstructive Surgery, Department of Surgery, University of Toronto; and the Division of Plastic and Reconstructive Surgery, University Health Network, University of Toronto.
Plast Reconstr Surg. 2019 Jul;144(1):1e-8e. doi: 10.1097/PRS.0000000000005695.
Microvascular breast reconstruction is a complex procedure that can be associated with high complication rates. Although a number of individual predictors of perioperative complications have been identified, few studies have explored interaction between risk factors. Understanding the synergistic effects of multiple risk factors is central to accurate and personalized preoperative risk prediction.
The authors conducted a retrospective cohort study of patients who underwent microvascular breast reconstruction at their institution between 2009 and 2017. All intraoperative and postoperative complications were recorded. A multivariable logistic regression exploratory model identified independent predictors of complications. Interactions between individual variables were then assessed using the relative excess risk index (RERI) and the synergy index (SI).
Nine hundred twelve patients were included in the study and 26.1 percent experienced at least one perioperative complication. Obesity (OR, 1.54; p = 0.009), immediate reconstruction (OR, 1.49; p = 0.028), and comorbidities (OR, 1.43; p = 0.033) were identified as independent predictors of complications. Obesity and comorbidities had significant synergistic interactions with immediate reconstruction (RERI, 0.86; SI, 2.35; p = 0.0002; and RERI, 0.54; SI, 1.78; p = 0.001), bilateral reconstruction (RERI, 0.12; SI, 1.15; p = 0.002; and RERI, 0.59; SI, 3.16; p = 0.005), and previous radiotherapy (RERI, 0.62; SI, 4.43; p = 0.01; and RERI, 0.11; SI, 1.23; p = 0.040). Patients undergoing immediate breast reconstruction who were both obese and smokers had a 12-fold increase in complication rates (OR, 12.68; 95 percent CI, 1.36 to 118.46; p = 0.026) with a very strong synergistic interaction between variables (RERI, 10.55; SI, 10.33).
Patient- and treatment-related variables interact in a synergistic manner to increase the risk of complications following microvascular breast reconstruction.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
微血管乳房重建是一种复杂的手术，可能会伴随高并发症发生率。虽然已经确定了许多围手术期并发症的个体预测因素，但很少有研究探索危险因素之间的相互作用。了解多个危险因素的协同效应是准确和个性化术前风险预测的关键。
作者对 2009 年至 2017 年在其机构接受微血管乳房重建的患者进行了回顾性队列研究。记录了所有术中及术后并发症。多变量逻辑回归探索性模型确定了并发症的独立预测因素。然后使用相对超额风险指数（RERI）和协同指数（SI）评估个体变量之间的相互作用。
本研究共纳入 912 例患者，26.1%的患者至少发生了一次围手术期并发症。肥胖（OR，1.54；p=0.009）、即刻重建（OR，1.49；p=0.028）和合并症（OR，1.43；p=0.033）被确定为并发症的独立预测因素。肥胖和合并症与即刻重建（RERI，0.86；SI，2.35；p=0.0002；和 RERI，0.54；SI，1.78；p=0.001）、双侧重建（RERI，0.12；SI，1.15；p=0.002；和 RERI，0.59；SI，3.16；p=0.005）和既往放疗（RERI，0.62；SI，4.43；p=0.01；和 RERI，0.11；SI，1.23；p=0.040）具有显著的协同相互作用。同时肥胖且吸烟的即刻乳房重建患者的并发症发生率增加了 12 倍（OR，12.68；95%CI，1.36 至 118.46；p=0.026），变量之间存在很强的协同相互作用（RERI，10.55；SI，10.33）。
患者和治疗相关的变量以协同方式相互作用，增加了微血管乳房重建后并发症的风险。
临床问题/证据水平：风险，III。
