Author + information
- Elmir Omerovic1
The PLATO trial has shown that ticagrelor compared to clopidogrel improves survival and decreases risk for stent thrombosis in patients with acute coronary syndrome (ACS). The aim of this study was to investigate whether treatment with ticagrelor is superior to clopidogrel in patients with ACS in “real-world”.
We used data from the SCAAR registry (Swedish Coronary Angiography and Angioplasty Registry) for the PCI procedures performed in Västra Götaland County in Sweden. The database contains information about all PCI procedures performed at five hospitals (∼20% of all SCAAR data). All consecutive procedures between 2005 and 2015 for UA/NSTEMI and STEMI were included. We used multilevel modeling based on complete–case mixed-effects logistic regression to adjust for hierarchical database due to clustering of observations. The following variables were used for adjustment of risk estimates: age; gender; hypertension; hyperlipidemia; smoking status; diabetes; calendar year; indication for PCI; prior MI, CABG and/or PCI; cardiogenic shock; severity of coronary artery disease; number of implanted stents; completeness of revascularization; type of stent. The primary combined endpoint was death or stent thrombosis at 30 days. The secondary end points were death at 30-days and death at one-year.
The total of 12,168 patients were included in the study of which 2,929 (19%) were treated with ticagrelor. 44% had STEMI. There were 555 events at 30-days of which 53 (9.5%) were stent thromboses. 844 patients were dead at one-year Treatment with ticagrelor was not associated with lower risk for primary endpoint (OR 0.97; 95% CI 0.66 - 1.43; P=0.887). Estimated risk of death at 30-days (OR 1.02; 95% CI 0.59 - 1.76; P=0.937) and one-year (OR 1.01; 95% CI 0.68 - 1.47; P=0.992) was not different between the groups. Sensitivity analysis has shown that for ticagrelor to reach statistical significance for independent association with the primary endpoint, the unmeasured confounder needs to have a relative risk >3 with prevalence of 40% in the ticagrelor group and 10% in the clopidogrel group.
In this observational study, treatment with ticagrelor was not superior to clopidogrel in patients with ACS treated with PCI.