November 3, 2016Open Access
Short term versus long term dual antiplatelet therapy after implantation of drug eluting stent in patients with or without diabetes: systematic review and meta-analysis of individual participant data from randomised trials
Key Result
Long term DAPT did not reduce MACE compared with short term DAPT in patients with (HR 1.05; 95% CI 0.62-1.76) or without diabetes (HR 0.97; 95% CI 0.67-1.39), but increased the risk of bleeding.
Study Design
Type
Meta-Analysis (n=11,473)
Multicenter
Yes
Structured PICO
Does long term (12 months) dual antiplatelet therapy reduce major adverse cardiac events compared to short term (up to 6 months) therapy in patients with and without diabetes after drug eluting stent implantation?
P
Population
11,473 patients from 6 randomized trials who underwent placement of a drug eluting stent, including 3,681 (32.1%) with diabetes (mean age 63.7) and 7,708 (67.2%) without diabetes (mean age 62.8).
I
Intervention
Long term (12 months) dual antiplatelet therapy (DAPT)
C
Comparator
Short term (up to 6 months) dual antiplatelet therapy (DAPT)
O
Outcome
One year risk of major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, or definite/probable stent thrombosiscomposite
Long-term (12 months) DAPT after drug-eluting stent implantation does not reduce MACE but increases bleeding risk compared to short-term (up to 6 months) DAPT, regardless of diabetes status.
Main Result
Effect estimate: HR 1.05 (diabetes) / HR 0.97 (no diabetes) (95% CI 0.62-1.76 (diabetes) / 0.67-1.39 (no diabetes))
p-value: p=0.86 (diabetes) / 0.85 (no diabetes)
Abstract
OBJECTIVE: To compare clinical outcomes between short term (up to 6 months) and long term (12 months) dual antiplatelet therapy (DAPT) after placement of a drug eluting stent in patients with and without diabetes. DESIGN: Individual participant data meta-analysis. Cox proportional regression models stratified by trial were used to assess the impact of diabetes on outcomes. DATA SOURCE: Medline, Embase, and Cochrane databases and proceedings of international meetings searched for randomised controlled trials comparing durations of DAPT after placement of a drug eluting stent. Individual patient data pooled from six DAPT trials. PRIMARY OUTCOME: Primary study outcome was one year risk of major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, or definite/probable stent thrombosis. All analyses were conducted by intention to treat. RESULTS: Six trials including 11 473 randomised patients were pooled. Of these patients, 3681 (32.1%) had diabetes and 7708 (67.2%) did not (mean age 63.7 (SD 9.9) and 62.8 (SD 10.1), respectively), and in 84 (0.7%) the information was missing. Diabetes was an independent predictor of MACE (hazard ratio 2.30, 95% confidence interval 1.01 to 5.27; P=0.048 At one year follow-up, long term DAPT was not associated with a decreased risk of MACE compared with short term DAPT in patients with (1.05, 0.62 to 1.76; P=0.86) or without (0.97, 0.67 to 1.39; P=0.85) diabetes (P=0.33 for interaction). The risk of myocardial infarction did not differ between the two DAPT regimens (0.95, 0.58 to 1.54; P=0.82; for those with diabetes and 1.15, 0.68 to 1.94; P=0.60; for those without diabetes (P=0.84 for interaction). There was a lower risk of definite/probable stent thrombosis with long term DAPT among patients with (0.26, 0.09 to 0.80; P=0.02) than without (1.42, 0.68 to 2.98; P=0.35) diabetes, with positive interaction testing (P=0.04 for interaction), although the landmark analysis showed a trend towards benefit in both groups. Long term DAPT was associated with higher rates of major or minor bleeding, irrespective of diabetes (P=0.37 for interaction). CONCLUSIONS: Although the presence of diabetes emerged as an independent predictor of MACE after implantation of a drug eluting stent, compared with short term DAPT, long term DAPT did not reduce the risk of MACE but increased the risk of bleeding among patients with stents with and without diabetes.