Extended duration antiplatelet therapy (DAPT) after drug-eluting stent implantation was linked to higher rates of mortality compared to shorter DAPT, a meta-analysis published in The Lancet has shown.

Researchers evaluated 31,666 patients from 10 randomized controlled trials between December 16, 2011 and November 16, 2014 that compared different DAPT durations after drug-eluting stent implantation. The primary endpoint was all-cause mortality. The team labeled DAPT duration in each study as “shorter vs. longer” and as “≤6 months vs. 1 year vs. >1 year.”

Study data showed that shorter DAPT was associated with significantly lower all-cause mortality vs. longer DAPT (HR 0.82, 95% CI: 0.69–0.98; P=0.02). The lower mortality rate was due to lower non-cardiac mortality (HR 0.67, 95% CI 0.52–0.89; P=0.006) with similar cardiac mortality (HR 0.93, 95% CI: 0.73–1.17; P=0.52).

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A shorter DAPT was linked to a reduced risk of major bleeding but an increased risk of myocardial infarction and stent thrombosis. Network meta-analysis showed patients treated with DAPT ≤6 months and 1 year had an increased risk of myocardial infarction and stent thrombosis, but a reduced risk of mortality vs. patients treated with DAPT >1 year. Patients treated with DAPT for ≤6 months had similar rates of mortality, myocardial infarction, and stent thrombosis, but lower rates of major bleeding than patients treated with DAPT 1 year.

Researchers concluded an extended DAPT (>1 year) may still be appropriate in some patients in whom prevention of stent and non-stent related coronary events are likely to outweigh the adverse events of extended DAPT. More studies are needed to identify the demographic, laboratory-based genetic variable that affect benefit vs. risk associated with extended DAPT.

For more information visit TheLancet.com.