Diabetes and coronary artery disease impose similar cardiovascular morbidity and mortality on renal transplant candidates.

Background: In renal transplant candidates (RTC), diabetes and coronary artery disease (CAD) are commonly observed. However, whether diabetes imparts a cardiovascular risk equivalent to that of CAD and whether CAD adds to the cardiovascular risk associated with diabetes is unknown.

Methods: To assess the interplay between diabetes and CAD as a determinant of major adverse cardiovascular events (MACE), 288 high-risk RTC (56.4+/-8.1 years old, 72% males) underwent a comprehensive cardiovascular evaluation including coronary angiography. Patients were divided into four groups based on the diagnoses of diabetes and CAD (>70% narrowing), and followed up for 1-60 months (median, 17). The primary endpoint was the composite incidence of fatal/non-fatal MACE.

Results: During follow-up, 80 MACE occurred. Patients with diabetes (P=0.03) or CAD (P<0.0001) had a worse long-term prognosis. However, only in patients without diabetes was CAD associated with an increased incidence of MACE (10.6% vs 45.9%, P<0.0001). In patients with diabetes, the endpoints were not different between those with and without CAD. No difference occurred in the long-term prognosis of patients with diabetes (with or without CAD) and patients without diabetes with CAD.

Conclusions: We concluded that in high-risk RTC, diabetes confers a cardiovascular risk comparable to that of CAD in patients without diabetes, independent of coronary obstruction. In patients with diabetes, concomitant CAD does not add to the already very high cardiovascular risk of this population.