Comparison of effectiveness and safety between ticagrelor and clopidogrel in patients with acute coronary syndrome and on dialysis in Taiwan

Aims This study aimed to evaluate and compare the effectiveness and safety between clopidogrel and ticagrelor in acute coronary syndrome (ACS) with renal dysfunction. Methods We conducted a retrospective cohort study on patients on chronic dialysis and whose admission diagnosis between 1 July 2013 and 31 December 2016 included ACS. The primary effectiveness endpoint was a major adverse cardiovascular event (MACE), and the primary safety endpoint was a major bleeding event. The application of propensity scores through the inverse probability of treatment weighting (IPTW) was applied to the study groups. Cox regression was used to estimate hazard ratios (aHRs) of study endpoints. In addition, the competing risk was adjusted using the Fine and Gray competing risk model. Results There were 1915 patients in the clopidogrel group and 270 patients in the ticagrelor group. At 12 months, the ticagrelor group had higher risks for MACE (aHR with IPTW: 1.29; 95% CI 1.16-1.44); death (aHR with IPTW: 1.65; 95% CI 1.47-1.86) and cardiac death (subdistribution HR [SHR] with IPTW: 1.64; 95% CI 1.41-1.91), compared with those in the clopidogrel group. For major bleeding event, the risk was significantly higher with ticagrelor than with clopidogrel (SHR with IPTW: 1.49; 95% CI 1.34-1.65). In terms of the risk for any bleeding event, there was no significant difference between the two groups (SHR with IPTW: 1.05; 95% CI 0.95-1.17). Conclusions Compared with clopidogrel, ticagrelor was associated with higher MACE, death, cardiac death and major bleeding risk within 12 months in patients with ACS and on dialysis.