Treatment pattern of contemporary dual antiplatelet therapies after acute coronary syndrome: a Swedish nationwide population-based cohort study

Abstract

Objectives: New dual antiplatelet therapies (DAPTs) have been introduced in clinical practice for patients with acute coronary syndrome (ACS). This nationwide study investigated DAPT patterns over time and patient characteristics associated with the various treatments in a population with ACS.

Design: This observational cohort study linked morbidity, mortality and medication data from Swedish national registries.

Results: Overall, 91% (104 012 patients) of all patients admitted to the hospital with an ACS (2009-2013) were alive after discharge and included in this study. Compared with 2009, in 2013 patients investigated with angiography increased by 10%, patients revascularized with percutaneous coronary intervention (PCI) increased by 11% and patients prescribed DAPT increased by 8%. Mean DAPT duration increased from 225 to 298 days in patients investigated with angiography, and from 155 to 208 days in patients who were not investigated with angiography. Furthermore, in patients undergoing angiography a treatment switch from clopidogrel to ticagrelor was observed. DAPT with prasugrel was used to a low extent. Approximately 10% of patients initiated on prasugrel or ticagrelor switched to clopidogrel during the first year of treatment.

Conclusion: During the study more patients underwent angiography and PCI. There was an increase in the proportion of ACS patients receiving DAPT, as well as longer duration of DAPT in line with ESC guidelines. Among DAPT-treated patients, ticagrelor has emerged as the preferred P2Y12 antagonist in patients undergoing angiography, whereas clopidogrel tended to be prescribed to patients treated non-invasively.

Keywords: Acute coronary syndrome; dual antiplatelet treatment; nationwide registry data.

Figure 1.

Flow chart.

Figure 2.

Proportion of patients discharged alive undergoing angiography and prescribed different types of dual antiplatelet treatment from 2009 to 2013.

Figure 3.

Persistence with different dual antiplatelet therapy in patients undergoing or not undergoing angiography from 2009 to 2013. Each point represents the number of patients with available medication divided by the number of patients alive at that time.