The Effect of Diabetes, Obesity, and Smoking on Mediastinitis After Coronary Artery Bypass Grafting: A Real-World Analysis

Background: Mediastinitis is an uncommon complication that can result from coronary artery bypass graft surgery with less than a 1% occurrence rate. But it can be quite deadly, with a mortality rate of 14–32%. Our hypothesis is that diabetes, obesity, and smoking all will increase the rate of this occurrence. Our aim is to evaluate the impact of diabetes, obesity, and smoking on the rate of mediastinitis following coronary artery bypass grafting.

Methods: TriNetX is a global health research network that provides preoperative and postoperative deidentified patient information such as demographics, diagnoses, and genomics, which is constantly updating itself. This study is a retrospective comparison of cohorts using TriNetX that were analyzed against a baseline to see if the rate of mediastinitis was higher in certain patients.

Results: A baseline of 12,625 healthy (not obese, smokers, or diabetic) patients were compared to each of the cohorts. The cohort containing people who smoke but are not obese or diabetic (n=3,713) were 1.73 times more likely to contract mediastinitis than the control (95% confidence interval 0.367–0.906, p<0.05). People with diabetes who are not obese or smokers (n=9,421) were 1.79 times more likely to develop mediastinitis (95% confidence interval 0.354–0.967, p<0.05). The group with diabetes and obesity but not smokers (n=5,174) were 2.85 times more likely to acquire mediastinitis (95% confidence interval, 1.942–4.126, p<0.01).

Conclusion: Our study is the first report in the surgical or wound literature to utilize TriNetX, a research network that democratizes data from EMRs. We demonstrate that diabetes and smoking are both independent risk factors for mediastinitis following a coronary artery bypass. Obesity and diabetes together are also a high risk factor.These results show the importance of understanding preoperative risk factors of mediastinitis when undergoing CABG.