Hyperglycemia as a risk factor for surgical site infections in patients undergoing mastectomy

Background: The aim of this study was to evaluate the association between perioperative hyperglycemia and surgical site infections (SSIs) in patients undergoing mastectomy. Methods: In this nested case-control study, patients undergoing mastectomy from May 2004 to June 2006, at the National Cancer Institute (INCan), Mexico, were included. Five blood glucose values were obtained for each patient. Patients were followed prospectively by direct observation for at least 30 days. Results: A total of 260 patients were included. Patient characteristics were similar in cases and controls. Cases were older (>50 years) (P =.001) and were more frequently treated with concomitant chemoradiation (P <.0001) than controls. Fifty cases (23.8%) developed an SSI. At least 1 measurement of blood glucose value >= 150 mg/dL increased the risk for SSI (odds ratio [OR] = 3.05; 95% confidence interval [CI] 1.5 to 6.3: P =.006). Variables associated with SSI after logistic regression analysis included age >50 years (OR = 3.7; 95 % Cl = 1.5 to 9.2; P =.005), preoperative concomitant chemoradiation treatment (OR = 2.8; 95 % Cl = 1.4 to 5.8, P =.0004), and any blood glucose value 150 mg/dL (OR = 2.9, 95 % Cl = 1.2 to 6.2; P =.02). Conclusion: Postoperative SSI was a very frequent complication in this cohort. Our data indicate that higher blood glucose values are an independent risk factor for postoperative SSI. Preoperative concomitant chemoradiation and age > 50 years were also risk factors for developing an SSI in patients undergoing mastectomy.