Everolimus Stent Better Than Paclitaxel Stent in Diabetic Patients, Even Those Requiring Insulin: TUXEDO Analysis

Using an everolimus-eluting stent as opposed to a paclitaxel-eluting stent to treat coronary artery disease in patients with insulin-dependent diabetes reduces the risk of clinical events, according to the results of a new study.

Overall, researchers found that treating insulin-dependent diabetics with an everolimus-eluting stent (Xience Prime, Abbott Vascular) reduced the rate of target vessel failure, major adverse cardiac events, any stent thrombosis, target lesion revascularization, and target vessel revascularization compared with treatment with a paclitaxel-eluting stent (Taxus Element, Boston Scientific).

“We know that older-generation stents are somewhat inferior, but the question was whether they were really inferior when you compare them in patients treated with insulin,” said lead investigator Sripal Bangalore, MD (NYU Langone Medical Center, New York, NY). “Hopefully this study puts that question to rest. In insulin-treated diabetic patients, the everolimus-eluting stent is far superior, even in terms of reducing stent thrombosis, compared with the Taxus stent.”

The new analysis, from the TUXEDO (Taxus Element vs Xience Prime in a Diabetic Population) study, was published online April 20, 2016, in JAMA: Cardiology.

Speaking with TCTMD, Bangalore said clinicians and researchers have known for some time that insulin-treated diabetic patients—most of whom have had diabetes for a longer duration than those whose disease is not insulin-treated—are “somewhat problematic” in PCI. To date, some studies have shown these patients have worse clinical outcomes after revascularization than those not receiving insulin, although others have suggested the increased risk disappears after adjusting for baseline risk factors.

In the main TUXEDO results, which were originally reported by TCTMD, investigators showed that diabetic patients with coronary artery disease fared significantly better after PCI if treated with an everolimus-eluting stent rather than a paclitaxel-eluting stent. TUXEDO was presented at TCT 2015 and published in the New England Journal of Medicine.   

Bangalore said the best choice of stent in diabetic patients requiring insulin remains unclear. He highlighted a combined analysis of the SPIRIT II, III, IV, and COMPARE studies showing that the everolimus-eluting stent reduced the rate of target lesion revascularization compared with a paclitaxel-eluting stent, but the advantage was observed only in those with non-insulin-dependent diabetes. In fact, there was a trend toward worse outcomes when compared with the paclitaxel-eluting stent in diabetic patients who required insulin.

In the TUXEDO study, 40.8% of the 1,830 patients were receiving insulin prior to revascularization. Overall, regardless of stent type, the insulin-treated diabetic patients had a significantly increased rate of target-vessel failure, major adverse cardiac events, death or MI, death, cardiac death, and subacute thrombosis when compared with 1,083 patients not treated with insulin. However, in a propensity score model that accounted for baseline variables, there was no increased risk of clinical events among the insulin-treated diabetic patients.

The suspicion that insulin-treated diabetic patients might be at higher risk for clinical events following revascularization is supported by animal studies suggesting insulin might cause inflammation and accelerate atherosclerosis, said Bangalore. In addition, they tend to be a higher-risk subgroup of diabetic patients, often with longer durations of disease and poorer glycemic control.

The absence of risk in the insulin-treated group after propensity score adjustment implies “that the increased possibility of adverse cardiovascular events in patients with [this type of diabetes] is accounted for by the differences in baseline risk factors, diabetes duration, and diabetes control,” say investigators. 

Regarding the selection of stent in patients with diabetes, the data should reassure physicians about using the Xience everolimus-eluting stent, even in those requiring insulin, said Bangalore. More than that, however, the study points to a significant advantage with the stent in the insulin-dependent diabetics, he said, with the everolimus-eluting stent reducing hard clinical endpoints, such as target vessel failure (3.4% vs 7.9%; P = 0.007), MACE (3.9% vs 8.2%; P = 0.01), MI (1.3% vs 4.4%; P = 0.01), and stent thrombosis (0.5% vs 3.0%; P = 0.009).

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