de-escalation from ticagrelor to clopidogrel in acute coronary syndrome patients: a systematic review and meta-analysis

De-escalation from ticagrelor to clopidogrel in acute coronary syndrome (acs) occur for a variety of reasons, including side effects (bleeding and non-bleeding) and costs. this study sought to assess the prevalence of de-escalation from ticagrelor to clopidogrel and the occurrence of adverse clinical outcomes following de-escalation. we conducted a systematic review of clinical trials and real-world studies in acs patients treated with ticagrelor. real-world data on the prevalence of de-escalation during hospitalization or at discharge, after hospital discharge, and during the whole study period were included for meta-analysis. major adverse cardiovascular events (mace) and bleeding events occurring after de-escalation were also assessed. a total of 12 studies were eligible for meta-analysis of the prevalence of de-escalation. de-escalation from ticagrelor to clopidogrel therapy occurred with a mean prevalence of 19.8% [95% confidence interval (ci) 11.2–28.4%]. de-escalation occurred more frequently in-hospital or at discharge than after hospital discharge (23.7% vs. 15.8%). for assessment of clinical outcomes, a total of six studies were eligible for meta-analysis. mean rate of mace for patients with de-escalation was 2.1% (95% ci 1.1–4.1%) and the rate of major bleeding events was 1.3% (95% ci 0.4–4.5%). in conclusion, de-escalation commonly occurs in real-world practice. although rates of major cardiovascular and bleeding events in this analysis were generally low, the profile of patients suitable for de-escalation, the impact of de-escalation on adverse clinical outcomes and how this is affected by the timing after index acs warrants further large-scale investigation.