Cardiac death, MI remain increased in patients with diabetes treated with DES

Among patients treated with drug-eluting stents during the DES era, researchers observed a higher rate of death or MI in those with diabetes compared with those without diabetes independent of lesion severity.

The researchers conducted a pooled analysis of patient-level data from 18 prospective randomized trials to determine whether patient lesion complexity at baseline had an impact on DES outcomes in a cohort of individuals stratified by diabetes status. They noted that previous studies of DES in individuals with or without diabetes have been associated with conflicting results.

Lesions were stratified as American College of Cardiology/American Heart Association class A/B1 vs. class B2/C in patients with or without diabetes. Outcomes for DES were compared in a propensity score matched analysis. Multivariate analysis results accounted for other baseline differences.

The data set included 3,467 individuals with diabetes who were matched with patients from the full cohort of 18,441 patients.

Diabetes predicted 1-year repeat revascularization, according to the results. Among patients in the diabetes group, the HR for target lesion revascularization at 1 year was 1.34 (95% CI, 1.05-1.70), and for target vessel revascularization it was 1.40 (95% CI, 1.15-1.72). Diabetes also predicted cardiac death or MI (HR=1.40; 95% CI, 1.09-1.81).

Patients with ACC/AHA type B2/C lesions had a TLR rate of 8% in the diabetes group and 4.5% in the non-diabetes group (P<.0001). TVR rates were also higher in patients with ACC/AHA type B2/C lesions who had diabetes compared with those who did not have diabetes (10.6% vs. 5.9%; P<.0001).

However, among those with type A/B1 lesions, the TLR rate was similar (diabetes group, 4.6% vs. non-diabetes group, 4.8%; P=.87), as was the rate of TVR (diabetes group, 7.4% vs. non-diabetes group, 6.8%; P=.47).

A significant interaction between diabetes and lesion type was reported for both TLR (P=.01) and TVR (P=.02). No such interaction existed for cardiac death or MI (P=.28).

“In the DES era, patients with [diabetes mellitus] remain at increased risk for cardiac death or MI,” the researchers concluded, adding that repeat revascularization risk is increased only in patients with diabetes who have complex lesions.

Stephen G. Ellis

Stephen G. Ellis, MD, of the department of cardiovascular medicine at the Cleveland Clinic Foundation, suggested in an accompanying editorial that the current analysis benefits from the large number of patients and “careful analysis.”

“It should be recalled, however, that most of the studies excluded patients with complex multi-lesion anatomy, hence limiting the generalizability of the results,” Ellis wrote. “In addition, it is uncertain if the results apply equally to all DES.”

Ellis suggested that current DES have reduced the differences in recurrence outcomes between individuals with or without diabetes in most lesions, but not for death or MI. “A step forward, yes, but a small one as stenting does not alter the aggressive panvascular aspect of diabetes,” he wrote.

PCI for individuals with diabetes may best be reserved for specific patient populations, including those with ACS or those who elect the procedure and have a “relatively simple anatomy at the lower end of diabetic risk spectrum for cardiovascular death or MI,” Ellis wrote. “Further, we need better therapies to quiescence the diabetic vasculopathy so that focal therapy of specific symptoms-causing stenoses can be associated with better long-term outcomes.”

For more information:

Ellis SG. J Am Coll Cardiol. 2014; [published online ahead of print March 12].

Kedhi E. J Am Coll Cardiol. 2014; [published online ahead of print March 12].

Disclosure: The researchers report financial disclosures with Abbott Vascular, AstraZeneca, Boston Scientific, Bristol-Myers Squibb/Sanofi Aventis, Covidien, Eli Lilly/Daiichi Sankyo, St. Jude Medical, Janssen, Maya Medical, Merck, Regado Biosciences, Sharp & Dohme and The Medicines Company. Ellis reports no relevant financial disclosures.