Lack of Association of Diabetes With Increased Postoperative Mortality and Cardiac Morbidity

HYPOTHESIS: A number of preoperative factors, including diabetes mellitus (DM), have been cited as increasing risk in patients undergoing major vascular operations. In smaller studies at our institution we have not found this to be apparent. This study reviewed all major vascular operations to confirm our bias that DM is not associated with increased mortality or cardiac morbidity. DESIGN: Case series retrospectively reviewed from a vascular registry established in 1990. SETTING: Tertiary care center. PATIENTS: Consecutive sample of 6565 patients who underwent lower extremity revascularization or carotid or aortic procedures, grouped by presence or absence of DM. MAIN OUTCOME MEASURES: Postoperative mortality, congestive heart failure, or myocardial infarction. RESULTS: Patients with DM made up 62.3% of the population, and those without diabetes, 37.7%. Average age of the DM group was 67.1 years, with 61.3% male and 38.7% female. Average age of the non-DM group was 70.6 years, with 61.8% male and 38.2% female. The rates of overall postoperative mortality, myocardial infarction, and congestive heart failure were 1.14%, 1.59%, and 1.13%, respectively. Comparing the DM with the non-DM group, these rates were 0.96% vs 1.46%, 1.77% vs 1.30%, and 1.13% vs 1.14%, respectively. Using multivariate analysis, the DM group had an inverse relationship to perioperative death, with an odds ratio of 0.53 (P =.01). The factors that were associated with increased mortality were hemodialysis and history of congestive heart failure. Previous myocardial infarction was the only factor that predicted postoperative myocardial infarction. Kaplan-Meier survival curves showed a significantly decreased survival in the DM group during the next 5 years (P<.001). CONCLUSIONS: Diabetes alone does not confer a higher mortality or cardiac morbidity rate with major vascular procedures. However, long-term survival is significantly worse in this group of patients.