No benefit of long-term antiplatelet therapy after DES implantation irrespective of diabetes status
medwireNews: Short-term dual antiplatelet therapy (DAPT) is as effective as long-term DAPT after implantation of a drug-eluting stent (DES) in patients with and without diabetes, study results suggest.
“Diabetes per se should not be a driver for prolonging DAPT over the mandatory period after implantation of a drug eluting stent because of increased risks compared with potential benefits of this strategy,” say Marco Valgimigli (Bern University Hospital, Switzerland) and colleagues.
In a meta-analysis of individual participant data from 11,473 patients, the researchers found that among those with diabetes, 3.3% of 1853 patients receiving long-term DAPT for at least 12 months experienced major adverse cardiac events (MACE), compared with 3.2% of 1828 patients given DAPT for 3–6 months (hazard ratio [HR]=1.05).
Similarly, in those without diabetes, MACE – defined as cardiac death, myocardial infarction, or definite or probable stent thrombosis – were observed in 2.1% of 3848 patients receiving long-term DAPT, versus 2.5% of 3860 receiving short-term DAPT (HR=0.97).
The meta-analysis included data from randomized controlled trials comparing short-term versus long-term DAPT with clopidogrel and aspirin in patients undergoing percutaneous coronary intervention with DES. In total, 32.1% of patients included in the analysis had medically confirmed diabetes.
“[C]ompared with short term DAPT, long term DAPT does not provide benefits in terms of ischaemic protection but rather increases the risk of bleeding, irrespective of diabetes status,” write the researchers in The BMJ.
While overall bleeding rates were similar in patients with and without diabetes, a significantly higher proportion of patients with diabetes receiving long-term DAPT experienced bleeding compared with diabetic patients on short-term DAPT, with rates of 2.1% and 1.1%, respectively (HR=1.89).
There was a nonsignificant increase in bleeding rates with long-term versus short-term DAPT among patients without diabetes. In accordance with previous research, the study authors also showed that the incidence of MACE was more than doubled in patients with diabetes compared with nondiabetic patients.
Commenting on Valgimigli and colleagues’ findings in an accompanying editorial, Jocasta Ball (Australian Catholic University, Melbourne, Victoria) notes that “having diabetes itself does not necessarily equate to a requirement for longer duration of DAPT,” and that the use of long-term DAPT “can actually do more harm than good.”
The study authors note that future research should “explore the optimal duration of DAPT according to the type of diabetes and its medical management.”
medwireNews is an independent medical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2016