Author + information
- Zaher Fanari1,
- Amratash Malodiya2,
- Sandra A. Weiss2,
- Sumaya Hammami1,
- Paul Kolm2 and
- William S. Weintraub2
The potential benefit of long-term dual antiplatelet therapy (DAPT) for secondary prevention of atherothrombotic events in patients with coronary artery disease (CAD) is unclear. Data from different randomized controlled trials (RCT) using different agents in different subgroups showed inconsistent results.
The goal of this study was to evaluate the efficacy and safety of long term DAPT for secondary prevention.
We performed a systematic review and meta-analysis from RCTs that tested different prolonged durations of DAPT for secondary prevention. Long term DAPT (L-DAPT) arm was defined as those receiving DAPT for more than 12 months. The long-term aspirin arm (L-ASA) was defined as those receiving either long-term aspirin monotherapy or DAPT for 6 months or less.
Our systematic literature search identified 2456 articles, of which 6 met the inclusion criteria for this analysis. These 6 RCT included a total of 47,734 patients (27657 L-DAPT and 20077 L-ASA). The use of L- DAPT was associated with a significant decrease in composite of death, myocardial infarction (MI) and stroke (6.08% vs. 6.71%; Odd Ratio OR= 0.86 [0.78 -0.94]; P=0.001). The reduction was mainly driven by a reduction in MI, but not in death, cardiac death or stroke. This reduction of death, MI and stroke was mainly noticed in patients with prior MI (6.32% vs. 7.28%; OR= 0.86 [0.79 -0.94]; P <0.001) but in those who had PCI with no MI. The reduction was seen with post PCI patients with prasugrel (3.10% vs. 5.90%; OR= 0.53 [0.37 -0.74]; P<0.001) and only in those with prior MI with clopidogrel (4.89% vs. 6.28% OR= 0.77 [0.66 -0.9]; P<0.01) and ticagrelor (6.95% vs. 5.72%; OR=0.84 [0.75 -0.93]; P=0.001). Long-term use of DAPT was associated with significant increase in major bleeding (1.47% vs. 0.88%; OR= 1.65 [1.23 - 2.21]; P=0.001).
Long-term use of DAPT for secondary prevention is associated with lower risk of death, MI and stroke in patients with prior MI, but it is associated with increased risk of bleeding. Prolonging DAPT requires careful assessment of the trade-off between ischemic and bleeding complications and should probably be reserved for those with highest risk for atherothrombotic events.