Screening asymptomatic diabetic patients for coronary artery disease prior to renal transplantation

Background. Coronary artery disease (CAD) is a significant contributor to excess mortality in renal transplant candidates with diabetes mellitus (DM). Prior studies relating to risk stratification for significant CAD in diabetics are confined to Caucasian type 1 DM patients. Methods. To assess the prevalence of clinically silent CAD and to identify variables that are associated with CAD, we retrospectively analyzed the cardiac catheterization data of 97 asymptomatic type 1 and 2 DM kidney and kidney-pancreas transplant candidates. Results. Thirty-three percent of type 1 and 48% of type 2 DM patients had significant stenosis (≥70%) in 1 or more coronary arteries. On multivariate logistic regression analysis, body mass index (BMI) >25 was significantly associated with CAD (relative risk = 4.8, P = 0.002). The age of the patient (7% increase in risk/year, P = 0.01; or relative risk = 3.0 if age >47 years, P = 0.032) and smoking history (2% increase in risk/pack-year of smoking, P = 0.10) were also associated with CAD. African American patients, who comprised 30% of the sample, had a 71% lower risk compared with Caucasian patients (P = 0.03). Factors that were not significantly associated with CAD included gender, type of diabetes, and whether dialyzed for >6 months prior to catheterization. Conclusions. We conclude that a notable proportion (approximately one-third to one-half) of asymptomatic type 1 and type 2 diabetic renal transplant candidates have significant CAD. Additionally, young African American DM patients with no smoking history and a BMI ≤25 are at reduced risk, and invasive tests may not be necessary in this group.