Does extended dual antiplatelet therapy improve outcomes in patients with acute coronary syndrome?

This study investigated the effects of prolonged dual antiplatelet therapy (DAPT) in patients with non-ST-segment elevation myocardial infarction (nSTEMI).

They found that longer use of DAPT was associated with lower mortality risk in these patients. 

Coronary artery disease (CAD) is a leading cause of mortality worldwide. CAD is caused by blockages in the arteries supplying the heart. Blockages can reduce blood flow or lead to clots. Managing CAD is very important. Many patients are diagnosed with CAD after a myocardial infarction (MI, heart attack). A heart attack is also called ST-segment elevation (STEMI). A non-STEMI (nSTEMI) is less common. 

Many patients with CAD present with what is called acute coronary syndrome (ACS). ACS may include STEMI or nSTEMI and other conditions like angina. ACS can be an early sign of a major heart attack. Drugs that thin the blood and prevent blockages are used to reduce the risk of a major heart attack. Two drugs are commonly prescribed. This is called dual antiplatelet therapy (DAPT). nSTEMI is less common in some populations. It is unclear if longer use of DAPT improves outcomes in patients with nSTEMI/ACS. 

This study included 13,005 patients with ACS. 2549 patients had nSTEMI. 90.8% of nSTEMI patients (2315) were prescribed DAPT. Follow-up was performed after 1 and 2 years. Most patients took aspirin and clopidogrel as DAPT. The main outcomes measured were the combined risks of death, MI and stroke. 

The rate of death, MI or stroke was lower in patients that took DAPT longer than 12 months (3.1% vs. 10.6%). The mortality rate was 8.4% in patients taking DAPT less than 12 months. Patients taking DAPT for more than 12 months had a 1.6% mortality rate. The number of major bleeding events was low in patients taking DAPT over 12 months. 

The authors concluded that longer use of DAPT was associated with lower mortality risk in patients with nSTEMI.

This study was conducted in an Asian population. 74% of participants were male and women were more likely to discontinue treatment. Other factors could have influenced the outcome of this study. More investigation is needed. 

If you have any concerns regarding CAD management please consult with your doctor.